Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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Monitoring van het voor vogels oogstbare voedselaanbod in de kombergingen van het Pinkegat en Zoutkamperlaag : rapportage t/m monitoringjaar 2018
Ens, Bruno J. ; Meer, Jaap van der; Troost, Karin ; Winden, Erik van; Schekkerman, Hans ; Rappoldt, Kees - \ 2019
Nijmegen : SOVON Vogelonderzoek Nederland (Sovon-rapport 2019/22) - 82
A Migratory Divide Among Red-Necked Phalaropes in the Western Palearctic Reveals Contrasting Migration and Wintering Movement Strategies
Bemmelen, Rob S.A. van; Kolbeinsson, Yann ; Ramos, Raül ; Gilg, Olivier ; Alves, José A. ; Smith, Malcolm ; Schekkerman, Hans ; Lehikoinen, Aleksi ; Petersen, Ib Krag ; Þórisson, Böðvar ; Sokolov, Aleksandr A. ; Välimäki, Kaisa ; Meer, Tim Van Der; Okill, J.D. ; Bolton, Mark ; Moe, Børge ; Hanssen, Sveinn Are ; Bollache, Loïc ; Petersen, Aevar ; Thorstensen, Sverrir ; González-Solís, Jacob ; Klaassen, Raymond H.G. ; Tulp, Ingrid - \ 2019
Frontiers in Ecology and Evolution 7 (2019). - ISSN 2296-701X - 17 p.
flexibility - itinerancy - migration strategy - Phalaropus lobatus - red-necked phalarope
Non-breeding movement strategies of migratory birds may be expected to be flexibly adjusted to the distribution and quality of habitat, but few studies compare movement strategies among populations using distinct migration routes and wintering areas. In our study, individual movement strategies of red-necked phalaropes (Phalaropus lobatus), a long-distance migratory wader which uses saline waters in the non-breeding period, were studied using light-level geolocators. Results revealed a migratory divide between two populations with distinct migration routes and wintering areas: one breeding in the north-eastern North Atlantic and migrating ca. 10,000 km oversea to the tropical eastern Pacific Ocean, and the other breeding in Fennoscandia and Russia migrating
ca. 6,000 km—largely over land—to the Arabian Sea (Indian Ocean). In line with our expectations, the transoceanic migration between the North Atlantic and the Pacific was associated with proportionately longer wings, a more even spread of stopovers in autumn and a higher migration speed in spring compared to the migration between Fennoscandian-Russian breeding grounds and the Arabian Sea. In the wintering period, van Bemmelen et al. Contrasting Movement Strategies in Phalaropes birds wintering in the Pacific were stationary in roughly a single area, whereas individuals wintering in the Arabian Sea moved extensively between different areas, reflecting differences in spatio-temporal variation in primary productivity between the two wintering areas. Our study is unique in showing how habitat distribution shapes movement strategies over the entire non-breeding period within a species.
Broedsucces van kustbroedvogels in de Waddenzee : Resultaten 2015-2016 en trends in broedsucces in 2005-2016
Koffijberg, K. ; Cremer, J.S.M. ; Boer, P. de; Nienhuis, J. ; Schekkerman, H. ; Oosterbeek, K. ; Postma, J. - \ 2017
Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-technical report 112) - 50
Data have been collected on the breeding success of several characteristic coastal breeding birds in the Wadden Sea each year since 2005. Ten birds species considered representative of specific habitats and food groups are being monitored. The monitoring scheme on breeding success in coastal breeding birds is run as an ‘early warning system’ to follow the reproductive capacity of the bird populations in the Wadden Sea and understand the processes underlying fluctuations in populations. It is a valuable addition to the monitoring of population numbers and is carried out under a trilateral agreement with Germany and Denmark (TMAP). The results from 2015–2016 and an analysis of data series from the period 2005–2016 (sometimes longer) show that several species on average reared too few young to sustain stable population size in many of these years, especially the Eurasian Oystercatcher, Pied Avocet, Common Tern and Arctic Tern, and in recent years also the Black-headed Gull, whose breeding success has significantly declined since 1995. Other species showing a significant decline in breeding success are the Spoonbill and Common Tern. The only species to show any significant improvement in breeding success since 2005 is the Lesser Black-backed Gull
Monitoring van het voor vogels oogstbare voedselaanbod in de kombergingen van het Pinkegat en Zoutkamperlaag
Ens, B.J. ; Krol, J. ; Meer, J. van der; Piening, H. ; Wijsman, J.W.M. ; Schekkerman, H. ; Rappoldt, C. - \ 2015
Nijmegen : Sovon (Sovon-rapport 2015.15) - 54
aardgas - nadelige gevolgen - natura 2000 - kustgebieden - vogels - waddenzee - foerageren - wetlands - groningen - friesland - natural gas - adverse effects - coastal areas - birds - wadden sea - foraging
De gaswinning vanaf de locaties Moddergat, Lauwersoog en Vierhuizen kan effecten hebben op het Natura 2000 gebied Waddenzee. Uit voorzorg vindt de winning plaats volgens het ‘Hand aan de kraan’ principe. In dat kader vindt een uitgebreide monitoring plaats van biotische en abiotische parameters, om te controleren of gaswinning vanaf de bovengenoemde locaties geen meetbaar nadelig effect heeft op de instandhoudingsdoelstellingen van de speciale beschermingzone Waddenzee, waaronder een groot aantal vogelsoorten waarvoor het gebied is aangewezen.
Site-specific dynamics in remnant populations of Northern Wheatears Oenanthe oenanthe in the Netherlands
Oosten, H.H. van; Turnhout, C. van; Hallmann, C.A. ; Majoor, F. ; Roodbergen, M. ; Schekkerman, H. ; Versluijs, R. ; Waasdorp, S. ; Siepel, H. - \ 2015
Ibis 157 (2015)1. - ISSN 0019-1019 - p. 91 - 102.
spatial synchrony - environmental correlation - scale - dispersal - birds - immigration - landscape - density - impact - space
Dynamics of populations may be synchronized at large spatial scales, indicating driving forces acting beyond local scales, but may also vary locally as a result of site-specific conditions. Conservation measures for fragmented and declining populations may need to address such local effects to avoid local extinction before measures at large spatial scales become effective. To assess differences in local population dynamics, we aimed to determine the demographic drivers controlling population trends in three remaining populations of the Northern Wheatear Oenanthe oenanthe in the Netherlands, as a basis for conservation actions. An integrated population model (IPM) was fitted to field data collected in each site in 2007–2011 to estimate fecundity, survival and immigration. Sites were 40–120 km apart, yet first-year recruits were observed to move between some of the sites, albeit rarely. All three populations were equally sensitive to changes in fecundity and first-year survival. One population was less sensitive to adult survival but more sensitive to immigration. A life table response experiment suggested that differences in immigration were important determinants of differences in population growth between sites. Given the importance of immigration for local dynamics along with high philopatry, resulting in low exchange between sites, creating a metapopulation structure by improving connectivity and the protection of local populations are important for the conservation of these populations. Site-specific conservation actions will therefore be efficient and, for the short term, we propose different site-specific conservation actions.
Shorebird incubation behviour and its influence on the risk of nest predation
Smith, P.A. ; Tulp, I.Y.M. ; Schekkerman, H. ; Gilchrist, H.G. ; Forbes, M.R. - \ 2012
Animal Behaviour 84 (2012)4. - ISSN 0003-3472 - p. 835 - 842.
daily energy-expenditure - site selection - parent birds - sandpipers - defense - pigmentation - patterns - habitat - success - waders
Both nest survival and incubation behaviour are highly variable among shorebirds (Charadrii), and we tested whether more conspicuous incubation behaviour increased the risk of nest predation. During 2000-2006, we monitored nest fate at 901 shorebird nests at three study sites across the circumpolar Arctic. Using miniature video recorders and nest temperature sensors, we obtained 782 days of behavioural data for 161 nests of 11 species. We related nest fate to the rate and duration of adults' nest absences or restless movements on the nest, as well as the total proportion of each day that adult birds engaged in these activities. Nest predation was positively related to the proportion of time that each species left the nest unattended. After controlling for species effects, the likelihood of a successful nesting attempt was lower for individuals that spent more time off the nest, but among failed nests, the number of days that a nest survived prior to depredation was not significantly predicted by measures of incubation behaviour. To control for weather or seasonal effects, we paired observations from nests that were ultimately depredated with observations from successful nests of the same species on the same day. In this paired sample (dominated by two species: red phalaropes, Phalaropus fulicarius, and little stints, Calidris minuta), both incubation recesses and restless movements were more numerous among failed versus successful nests. Our results suggest that more conspicuous incubation behaviour is indeed related to a higher risk of nest predation, and that this relationship may underlie patterns of nest survival within and among shorebird species. (C) 2012 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
Eggs in the Freezer: energetic Consequences of Nest Site and Nest Design in Arctic Breeding Shorebirds
Tulp, I.Y.M. ; Schekkerman, H. ; Leeuw, J.J. de - \ 2012
PLoS ONE 7 (2012)6. - ISSN 1932-6203 - 9 p.
mating system - heat-loss - incubation - predation - expenditure - insulation - sandpipers - selection - clutch - tundra
Birds construct nests for several reasons. For species that breed in the Arctic, the insulative properties of nests are very important. Incubation is costly there and due to an increasing surface to volume ratio, more so in smaller species. Small species are therefore more likely to place their nests in thermally favourable microhabitats and/or to invest more in nest insulation than large species. To test this hypothesis, we examined characteristics of nests of six Arctic breeding shorebird species. All species chose thermally favourable nesting sites in a higher proportion than expected on the basis of habitat availability. Site choice did not differ between species. Depth to frozen ground, measured near the nests, decreased in the course of the season at similar non-species-specific speeds, but this depth increased with species size. Nest cup depth and nest scrape depth (nest cup without the lining) were unrelated to body mass (we applied an exponent of 0.73, to account for metabolic activity of the differently sized species). Cup depth divided by diameter2 was used as a measure of nest cup shape. Small species had narrow and deep nests, while large species had wide shallow nests. The thickness of nest lining varied between 0.1 cm and 7.6 cm, and decreased significantly with body mass. We reconstruct the combined effect of different nest properties on the egg cooling coefficient using previously published quantitative relationships. The predicted effect of nest cup depth and lining depth on heat loss to the frozen ground did not correlate with body mass, but the sheltering effect of nest cup diameter against wind and the effects of lining material on the cooling coefficient increased with body mass. Our results suggest that small arctic shorebirds invest more in the insulation of their nests than large species
Do Uniparental Sanderlings Calidris alba Increase Egg Heat Input to Compensate for Low Nest Attentiveness?
Reneerkens, J. ; Grond, K. ; Schekkerman, H. ; Tulp, I.Y.M. ; Piersma, Th. - \ 2011
PLoS ONE 6 (2011)2. - ISSN 1932-6203 - 9 p.
daily energy-expenditure - incubation schedules - avian embryos - tree swallows - clutch size - wood ducks - temperature - behavior - demands - birds
Birds breeding in cold environments regularly have to interrupt incubation to forage, causing a trade-off between two mutually exclusive behaviours. Earlier studies showed that uniparental Arctic sandpipers overall spend less time incubating their eggs than biparental species, but interspecific differences in size and ecology were potential confounding factors. This study reports on a within-species comparison of breeding schedules and metal egg temperatures in uni- and biparental sanderlings (Calidris alba) in Northeast Greenland in relation to ambient temperature. We recorded incubation schedules with nest temperature loggers in 34 sanderling clutches (13 uniparentals, 21 biparentals). The temperature of a metal egg placed within the clutch of 17 incubating birds (6 uniparentals, 9 biparentals) was measured as an indicator of the heat put into eggs. Recess frequency, recess duration and total recess time were higher in uniparentals than in biparentals and positively correlated with ambient temperatures in uniparentals only. Uniparental sanderlings maintained significantly higher metal egg temperatures during incubation than biparentals (1.4°C difference on average). Our results suggest that uniparental sanderlings compensate for the lower nest attendance, which may prolong the duration of the incubation period and negatively affect the condition of the hatchlings, by maintaining a higher heat flux into the eggs.
Broedsucces van kustbroedvogels in de Waddenzee in 2007 en 2008
Kleunen, A. van; Koffijberg, K. ; Boer, P. ; Nienhuis, J. ; Camphuysen, C.J. ; Schekkerman, H. ; Oosterbeek, K.H. ; Jong, M.L. de; Ens, B.J. ; Smit, C.J. - \ 2010
Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-werkdocument 227) - 73
broedvogels - watervogels - voortplantingsvermogen - kustgebieden - monitoring - populatiedynamica - waddenzee - breeding birds - waterfowl - reproductive performance - coastal areas - monitoring - population dynamics - wadden sea
Voor het derde en vierde opeenvolgende jaar werd het broedsucces van een aantal kustbroedvogels in de Waddenzee bepaald. Van Eider, Scholekster, Kluut, Kokmeeuw, Zilvermeeuw en Visdief, alsmede van Kleine Mantelmeeuw en Noordse Stern werd informatie verzamelen over het nestsucces en uitvliegsucces (het uiteindelijke broedsucces). Kennis over de jaarlijkse variatie in broedresultaten bij de verschillende soorten is van belang als een early warning systeem om de 'kwaliteit' (het reproducerend vermogen) van de vogelpopulaties in de Waddenzee te volgen en de achterliggende processen van populatieveranderingen te doorgronden. Directe aanleiding voor het project vormde de evaluatie van de effectiviteit van het nieuwe schelpdiervisserijbeleid en de mogelijke gevolgen voor de voedselvoorziening van schelpdieretende vogels.
Effect van nestbezoek en onderzoek op weidevogels
Goedhart, P.W. ; Teunissen, W.A. ; Schekkerman, H. - \ 2010
Wageningen : Wageningen Universiteit (SOVON-onderzoeksrapport 2010/01) - 84
weidevogels - natuurbescherming - cost effective analysis - ecologische modellering - beslissingsmodellen - grassland birds - nature conservation - cost effectiveness analysis - ecological modeling - decision models
In Nederland wordt veel energie gestoken in het zoeken en beschermen van weidevogellegsels tegen agrarische activiteiten om zo de gestage achteruitgang van weidevogels te stoppen. Jaarlijks betreft dit zo’n 150.000 nesten. Er is echter discussie ontstaan over het positieve effect van dit soort beschermingsmaatregelen omdat het controleren van nesten tot een verhoging van de verliezen zou kunnen leiden; het zogenaamde bezoekeffect. Om dit vast te kunnen stellen is allereerst gezocht naar een berekeningswijze waarmee een eventueel bezoekeffect kan worden aangetoond. Hiervoor zijn in totaal drie verschillende modellen ontwikkeld en getest. De verschillende modellen zijn uitgetest met een gesimuleerde dataset waarin de waarden voor de dagelijkse overlevingskans en het bezoekeffect bekend zijn. De beste schattingen van het bezoekeffect en de dagelijkse overlevingskans worden behaald met een model waarin tevens de broedduur en de eerste eilegdatum zijn gemodelleerd.
Population dynamics of Black-tailed Godwits in the light of heavy metal pollution
Roodbergen, M. - \ 2010
University of Groningen. Promotor(en): T. Piersma, co-promotor(en): Chris Klok; H. Schekkerman. - - 170
limosa limosa - verontreinigde grond - zware metalen - populatiedynamica - contaminated soil - heavy metals - population dynamics
Wat kost het behoud van onze akkervogels?
Bos, J.F.F.P. ; Sierdsema, H. ; Schekkerman, H. ; Scharenburg, C.W.M. - \ 2010
De Levende Natuur 111 (2010)6. - ISSN 0024-1520 - p. 259 - 263.
vogels - bouwland - gemeenschappelijk landbouwbeleid - kosten - agrarisch natuurbeheer - birds - arable land - cap - costs - agri-environment schemes
Het Planbureau voor de Leefomgeving wilde weten welke maatregelen in de Nederlandse landbouw nodig zijn om akkervogeldoelen te halen en wat deze maatregelen kosten. In het rapport "Een veldleeuwerik zingt niet voor niets!" zijn deze vragen beantwoord. Dit artikel geeft de belangrijkste bevindingen.
Adverse effectsof agricultaral intensification and climate change on breeding habitat quality of Blacktailed Godwits Limosa l. limosa in the Netherlands
Kleijn, D. ; Schekkerman, H. ; Dimmers, W.J. ; Kats, R.J.M. van; Melman, T.C.P. ; Teunissen, W.A. - \ 2010
Ibis 152 (2010)3. - ISSN 0019-1019 - p. 475 - 486.
farmland bird populations - lapwing vanellus-vanellus - agri-environment schemes - grassland management - chicks - eggs - biodiversity - intensity - britain - europe
Agricultural intensification is one of the main drivers of farmland bird declines, but effects on birds may be confounded with those of climate change. Here we examine the effects of intensification and climate change on a grassland breeding wader, the Black-tailed Godwit Limosa l. limosa, in the Netherlands. Population decline has been linked to poor chick survival which, in turn, has been linked to available foraging habitat. Foraging habitat of the nidifugous chicks consists of uncut grasslands that provide cover and arthropod prey. Conservation measures such as agri-environment schemes aim to increase the availability of chick foraging habitat but have not yet been successful in halting the decline. Field observations show that since the early 1980s, farmers advanced their first seasonal mowing or grazing date by 15 days, whereas Godwits did not advance their hatching date. Ringing data indicate that between 1945 and 1975 hatching dates advanced by about 2 weeks in parallel with the advancement of median mowing dates. Surprisingly, temperature sums at median mowing and hatching dates suggest that while the agricultural advancement before 1980 was largely due to agricultural intensification, after 1980 it was largely due to climate change. Examining arthropod abundance in a range of differently managed grasslands revealed that chick food abundance was little affected but that food accessibility in intensively used tall swards may be problematic for chicks. Our results suggest that, compared with 25 years ago, nowadays (1) a much higher proportion of clutches and chicks are exposed to agricultural activities, (2) there is little foraging habitat left when chicks hatch and (3) because of climate change, the vegetation in the remaining foraging habitat is taller and denser and therefore of lower quality. This indicates that for agri-environment schemes to make a difference, they should not only be implemented in a larger percentage of the breeding area than the current maxima of 20–30% but they should also include measures that create more open, accessible swards
Een veldleeuwerik zingt niet voor niets! : schatting van kosten van maatregelen voor akkervogels in de context van een veranderend gemeenschappelijk landbouwbeleid
Bos, J.F.F.P. ; Sierdsma, H. ; Schekkerman, H. ; Scharenburg, C.W.M. - \ 2010
Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-rapport 107) - 242
vogels - gemeenschappelijk landbouwbeleid - akkerbouw - kosten - agrarisch natuurbeheer - birds - cap - arable farming - costs - agri-environment schemes
Als gevolg van intensivering en schaalvergroting nemen de aan landbouw gebonden vogelsoorten op Europese schaal zowel in aantal als verspreiding af. Door hun verbondenheid met landbouw is het lot van akkervogels nauw gerelateerd aan de effecten van het Europese Gemeenschappelijk Landbouwbeleid (GLB). Afhankelijk van de uitwerking van dit GLB na 2013 neemt de betekenis van gerichte betalingen aan de landbouw voor specifieke doelen, waaronder biodiversiteit, mogelijk toe. Binnen de context van een veranderend GLB enerzijds en biodiversiteitsdoelstellingen voor akkervogels anderzijds, verschaft dit rapport inzicht in de (kosten van) maatregelen die in de Nederlandse landbouw op landelijk niveau nodig zijn om biodiversiteitsdoelstellingen voor akkervogels te behalen. Alle maatregelen richten zich op het voorzien in de ‘grote drie’ voor akkervogels: broedgelegenheid en dekking, voldoende aanbod van toegankelijk zomervoedsel (insectenrijke habitats in nabijheid van nest) en voldoende aanbod van wintervoedsel (graankorrels, onkruidzaden). De geschatte kosten van de maatregelen bedragen minimaal enkele tientallen miljoenen tot maximaal €176 miljoen. Trefwoorden: akkervogels, agrarisch natuurbeheer, Gemeenschappelijk landbouwbeleid, biodiversiteit
Mortality of Black-tailed Godwit Limosa limosa and Northern Lapwing Vanellus vanellus chicks in wet grasslands: influence of predation and agriculture
Schekkerman, H. ; Teunissen, W. ; Oosterveld, E. - \ 2009
Journal of Ornithology 150 (2009)1. - ISSN 2193-7192 - p. 133 - 145.
curlew numenius-arquata - breeding success - duckling survival - pheasant chicks - population - management - birds - brood - parameters - abundance
Grassland-breeding shorebirds show widespread declines due to a reduction in breeding productivity following agricultural intensification. However, there is also concern that increasing predation causes further declines or precludes population recovery. Predation may itself be enhanced by agriculture through changes in habitat or food availability, but little is known about the mortality of nidifugous shorebird chicks. We studied mortality by radio-tagging 662 chicks of Black-tailed Godwit Limosa limosa and Northern Lapwing Vanellus vanellus in 15 farmland sites in the Netherlands. Tagging and handling had no effect on the condition and survival of godwit chicks, but body condition was reduced by 6-11% in lapwing chicks wearing a tag for longer than 3 days. Fledging success was 0 - 24% in both species. Mortality was highest in young chicks but remained considerable until after fledging. Losses were traced mostly to predators (70 - 85%; 15 species, predominantly birds), but at least 5 - 10% were due to mowing, and 10 - 20% were due to other causes, including entrapment in ditches and starvation. Chicks staying in fields that were cut before the next radio check were found much more often as mowing victims and somewhat more often as prey remains than chicks in fields not cut, indicating that predation includes a limited amount of scavenging. The predation hazard for godwit chicks was higher in recently cut or grazed fields than in the tall, uncut grasslands they preferred, while that for lapwing chicks was lowest in grazed fields. In godwit chicks, poor body condition increased mortality risk, not only from starvation but also from other causes. Predation on godwit chicks was thus enhanced by intensive farming through a decline in the availability of cover, augmented by a reduced body condition, possibly due to food availability problems. Changes in farming practice may therefore help reduce predation pressure, though the observed interactions explained only part of the high predation rate in godwits and none in lapwings. Predator abundance has increased in Dutch wet grassland regions, and chick predation has become a factor that should be considered in planning the type and location of conservation measures.
Do meadow birds profit from agri-environment schemes in Dutch agricultural landscapes?
Breeuwer, A.J.G. ; Berendse, F. ; Willems, F. ; Foppen, R. ; Teunissen, W. ; Schekkerman, H. ; Goedhart, P.W. - \ 2009
Biological Conservation 142 (2009)12. - ISSN 0006-3207 - p. 2949 - 2953.
godwit limosa-limosa - farmland - biodiversity - intensification - management - abundance - success
Since 1992 the European Union helps member states to reverse the loss of biodiversity in agricultural landscapes by the financial support of agri-environment schemes. Long-term studies investigating the effects of these schemes are an essential prerequisite for the development of an effective policy to restore biodiversity on farmland. In Dutch meadow landscapes almost all agri-environment schemes focus on the restoration of meadow bird populations by postponement of the mowing date. Between 1990 and 2002 we measured long-term changes in meadow bird densities in areas with and without agri-environment schemes in the Netherlands, both before and after the start of the contract. During these years bird territories were surveyed during five field visits between 15 March and 15 June. Densities of black-tailed godwit (Limosa limosa), and redshank (Tringa totanus) were higher in the areas with management agreements, but these differences were already present before the start of the contracts. After the start of the management contracts densities of black-tailed godwit and oystercatcher (Haematopus ostralegus) did not increase, while those of lapwing (Vanellus vanellus) and redshank even declined relative to the control areas. It is concluded that the current agri-environment schemes are not sufficient to restore meadow bird populations in Dutch agricultural landscapes. In addition to the prescribed postponement of the mowing date, it is probably necessary to raise groundwater levels and to reduce fertilization to allow for the development of an open vegetation structure that will increase chick survival to sufficiently high levels
Body condition of shorebirds upon arrival at their Siberian breeding grounds
Tulp, I.Y.M. ; Schekkerman, H. ; Klaassen, R.H.G. ; Ens, B.J. ; Visser, G.H. - \ 2009
Polar Biology 32 (2009)3. - ISSN 0722-4060 - p. 481 - 491.
calidris-canutus-islandica - red knots - energy-expenditure - tundra arthropods - ellesmere-island - fat reserves - migration - stores - survival - waders
Abstract Arctic breeding shorebirds carry substantial body stores on their long-distance migrations from their non-breeding grounds. Upon arrival at the breeding area the remains of these stores can be used for egg formation, insurance against poor feeding conditions or rebuilding organs. We quantified body condition (body mass, total body water, lean body mass and fat mass estimated using the deuterium dilution method) in seven shorebird species caught upon arrival in the Siberian Arctic. Arrival condition was compared with incubation condition in a subset of species. After correction for structural size, body mass was significantly lower at arrival than during incubation in most of the species (but 3¿18% above lean mass). Fat index (fat mass/lean mass) varied between 5.1 and 13.2%. Fat stores were estimated to enable survival for 0.6 days for the smallest and 2.5 days for the largest species. We discuss possible functions of arrival stores: insurance, egg-formation or rebuilding organs.
Energetic demands during incubation and chick rearing in a uniparental and a biparental shorebird breeding in the high Arctic
Tulp, I.Y.M. ; Schekkerman, H. ; Bruinzeel, L. ; Jukema, J. ; Visser, G.H. ; Piersma, T. - \ 2009
The Auk : a quarterly journal of ornithology 126 (2009)1. - ISSN 0004-8038 - p. 155 - 164.
labeled water method - temperature regulation - expenditure - birds - allocation - waders - reproduction - validation - sandpipers - patterns
Rearing of young has long been considered the energetically most demanding phase of the avian breeding cycle. Arctic-breeding shorebirds expend large amounts of energy during breeding. Because they are too small to carry sufficient stores to sit out the incubation period, they regularly interrupt incubation to feed and still can run short of energy, particularly in species in which one adult takes care of the eggs and chicks alone (uniparental). We measured daily energy expenditure (DEE) and time budgets during incubation and chick rearing in the smallest uniparental Arctic shorebird, the Little Stint (Calidris minuta). Daily energy expenditure decreased with increasing temperature but did not differ between the incubation and chick-rearing periods. Because of the increase in potential foraging time from incubation to the chick-rearing phase, the foraging intake rate required to balance the budget dropped by two-thirds. To evaluate the effect of uniparental care on energy budgets, we also measured DEE in the Dunlin (C. alpina), a sympatric congener in which both parents incubate but the female deserts the brood after hatching. Daily energy expenditure decreased with temperature, was the same during incubation and chick rearing, and was higher in males. Our results are discussed in relation to the timing of breeding of Arctic shorebirds with different systems of parental care. Received 31 October 2007, accepted 28 September 2008.
The effect of 'mosaic management' on the demography of black-tailed godwit Limosa limosa on farmland
Schekkerman, H. ; Teunissen, W. ; Oosterveld, E. - \ 2008
Journal of Applied Ecology 45 (2008)4. - ISSN 0021-8901 - p. 1067 - 1075.
agri-environment schemes - bird populations - agricultural intensification - food resources - success - chicks - biodiversity - netherlands - grasslands - survival
1. Like many farmland birds, the largest European population of the black-tailed godwit Limosa limosa, in The Netherlands, has been declining for decades despite conservation measures including agri-environment schemes (AES). In a new experimental AES aiming to reverse this decline, collectives of farmers implemented spatially coordinated site-level habitat management ('mosaic management') including delayed and staggered mowing of fields, refuge strips and active nest protection. 2. We evaluated the effectiveness of mosaic management by measuring godwit breeding success in six experimental sites and paired controls. Productivity was higher in mosaics than in controls due to fewer agricultural nest losses. Chick fledging success was poor in both treatments. Productivity compensated for adult mortality in only one AES site. 3. Although creating chick habitat was a major management goal, the availability of tall grass during the fledging period did not differ between treatments, mainly because rainfall delayed mowing in all sites and study years. However, chick survival increased with the availability of tall grass among sites. Higher chick survival will thus enhance the positive effect of mosaic management in drier years, but sensitivity to weather represents a weakness of the AES design. 4. Available estimates of productivity in Dutch godwits suggest a strong reduction over the past 20 years and implicate chick survival as the main driver of their decline. Earlier mowing of grassland is the main causal mechanism, but changes in vegetation structure and composition, and increased predation may also have contributed. 5. Synthesis and applications. Demographic rates like breeding success are useful parameters for evaluating effects of management. Mosaic management increases the productivity of black-tailed godwits, but does not ensure long-term population viability for this flagship species of wet grassland bird communities. More stringent management prescriptions need to improve both the area and the quality (vegetation structure) of grassland mown late. Management efforts should be concentrated in areas with favourable pre-conditions in order to improve overall effectiveness.
Identifying predators of eggs and chicks of Lapwing Vanellus vanellus and Black-tailed Godwit Limosa limosa in the Netherlands and the importance of predation on wader reproductive output
Teunissen, W. ; Schekkerman, H. ; Willems, F. ; Majoor, F. - \ 2008
Ibis 150 (2008)Suppl. 1. - ISSN 0019-1019 - p. 74 - 85.
crow predation - nest-predation - success - population - management - farmland - grasslands - survival - britain - birds
Farmland bird populations in the Netherlands have shown an accelerating decline in recent years, despite extensive conservation efforts including reserves, agri-environment schemes and protection of nests by volunteers. Although agricultural intensification is the main cause underlying these declines, there is a growing concern that the ongoing decline of grassland-breeding shorebirds in recent years is caused or aggravated by increasing predation. Although Red Fox Vulpes vulpes and Carrion Crow Corvus corone are often accused of causing widespread breeding losses, and calls for management of these species are made, very few field data are available on the incidence of predation on grassland shorebirds and the relative importance of different predators. To obtain such data, we identified egg predators using temperature loggers and continuous video recordings of 792 clutches, and chick predators by radiotagging 662 chicks of Black-tailed Godwit Limosa limosa and Northern Lapwing Vanellus vanellus. In total, 22 species were identified as predators of eggs or chicks, of which Red Fox, Common Buzzard Buteo buteo, Grey Heron Ardea cinerea and Stoat Mustela erminea were the most frequent. Eggs were taken primarily by mammals and chicks more often by birds. There was great variation in predation levels and species involved in predation of clutches between sites and years, but less in chick predation. Hence, there was no correlation between predation levels on clutches and those on chicks within the same sites. In sites where more then 50% of clutches were lost to predation, however, nocturnal predators took the larger share. As temporal and spatial variation on a small scale significantly influences predation levels, a site-specific approach based on sound knowledge of the local situation will be more effective in reducing predation on farmland birds than general, country-wide measures. Calculations based on our data indicate that eliminating only one loss factor at a time will often not reverse a local population decline, and provide a strong argument for targeting several locally limiting factors simultaneously instead of focusing on mitigation of predation alone.
Factoren die de overleving van weidevogelkuikens beïnvloeden
Teunissen, W. ; Klok, T.C. ; Kleijn, D. ; Schekkerman, H. - \ 2008
Ede : Directie Kennis, Ministerie van Landbouw, Natuur en Voedselkwaliteit (SOVON nr. 2008/01) - 80
vogels - onvolwassenheid - overleving - dierecologie - monitoring - weidevogels - agrarisch natuurbeheer - birds - juvenility - survival - animal ecology - monitoring - grassland birds - agri-environment schemes
Uit onderzoek naar de effectiviteit van het huidige weidevogelbeheer komt telkens naar voren dat er voor de ontwikkeling van een beter beheer op een aantal punten nog onvoldoende kennis aanwezig is over factoren die van belang zijn voor de overleving van weidevogelkuikens. Die ontbrekende kennis spitst zich toe op de invloed die weer, voedsel en beheer op de conditie en daarmee op de overleving van kuikens hebben. Een deel van de vragen kan alleen worden beantwoord door nieuw opgezet veldwerk, maar een deel kan wel beantwoord worden op grond van nieuwe analyses en bestaande datasets . De belangrijkste uitkomsten van die analyses worden hieronder beschreven.
The ongoing decline of the breeding population of Black-tailed Godwits Limosa l. limosa in The Netherlands is not explained by changes in adult survival
Roodbergen, M. ; Klok, C. ; Schekkerman, H. - \ 2008
Ardea 96 (2008)2. - ISSN 0373-2266 - p. 207 - 218.
redshank tringa-totanus - west-african rainfall - warblers acrocephalus-schoenobaenus - stork ciconia-ciconia - natal dispersal - site fidelity - purple heron - rates - drought - consequences
The Black-tailed Godwit Limosa limosa is a characteristic breeding wader of wet grasslands in the Netherlands which has suffered a strong population decline since the 1960s. Low breeding success has been implicated as the main driver of this decline and here we examine whether changes in adult survival could also have played a role. Adult godwits were colour-ringed and resighted from 2002 through 2005 at four study sites in the Netherlands. Apparent adult survival was estimated in program MARK using Burnham¿s model for both live resightings and dead recoveries. In addition, nest site fidelity was estimated at two of the sites by recording the distance between nest locations in successive years. Apparent adult survival was 0.93 (SE 0.03) in one study area and 0.81 (SE 0.04) in the other three sites. Overall apparent adult survival was 0.83 (SE 0.03). These values are similar to estimates from the 1970s and 1980s. Nest site fidelity was higher in the site with highest survival (median distance between nests in successive years: 49 m vs. 252 m in the other site), suggesting that the difference in apparent survival may result from differences in emigration rates. Thus, our results suggest that current adult survival is not different from rates 30 years ago, and therefore do not point to reduced adult survival as the driver behind the current population decline of Black-tailed Godwits.
Ecologische kenmerken van weidevogeljongen en de invloed van beheer op overleving. Kennisoverzicht en effectiviteit van maatregelen
Oosterveld, E.B. ; Kleijn, D. ; Schekkerman, H. - \ 2008
Ede : Directie Kennis, Ministerie van Landbouw, Natuur en Voedselkwaliteit (Rapport / DK nr. 2008/090) - 72
vogels - onvolwassenheid - overleving - dierecologie - weidevogels - birds - juvenility - survival - animal ecology - grassland birds
Rapport over de effectiviteit van beheersmaatregelen voor overleving van primaire weidevogelkuikens in graslanden, op basis van wetenschappelijke en niet-wetenschappelijke literatuur. Per sprake komen: Ecoprofielen weidevogeljongen van: Kievit (Vanellus vanellus); Grutto (Limosa limosa); Tureluur (Tringa totanus); Scholekster (Haematopus ostralegus); Watersnip (Gallinago gallinago); Kemphaan (Philomachus pugnax); Slobeend (Anas clypeata); Zomertaling (Anas querquedula); Kuifeend (Aythya fuligula); Veldleeuwerik (Alauda arvensis); Graspieper (Anthus pratensis); Gele kwikstaart (Motacilla flava)
Precocial problems : shorebird chick performance in relation to weather, farming, and predation
Schekkerman, H. - \ 2008
University of Groningen. Promotor(en): T. Piersma; G.H. Visser. - Wageningen : Alterra - ISBN 9789090229799 - 228
vogels - predatie - voedingsgedrag - kuikens - jonge dieren - weidevogels - agrarisch natuurbeheer - birds - predation - feeding behaviour - chicks - young animals - grassland birds - agri-environment schemes
De afname van Nederlandse weidevogelpopulaties wordt mede veroorzaakt door problemen die kuikens bij het foerageren op insecten ondervinden. Het maaien van grasland leidt tot een sterke afname in het voedselaanbod, en een vervroeging van maaidatums in de afgelopen decennia heeft de foerageeromstandigheden voor kuikens sterk verslechterd. Tegelijkertijd zijn ook nog niet gemaaid graslandvegetaties minder geschikt geworden als kuikenhabitat door veranderingen in hun samenstelling en structuur, en is de predatiedruk op kuikens toegenomen. Het uitstellen van de maaidatum alleen is daardoor vaak niet meer voldoende om grutto’s voldoende jongen groot te laten brengen
Has prey availability for Arctic birds advanced with climate change? Hindcasting the abundance of tundra Arthropods using weather and seasonal variation
Tulp, I.Y.M. ; Schekkerman, H. - \ 2008
Arctic 61 (2008)1. - ISSN 0004-0843 - p. 48 - 60.
sandpiper calidris alpina - long-distance migrant - avian reproduction - migratory birds - life-cycles - snow-cover - alaska - insects - arrival - growth
Of all climatic zones on earth, Arctic areas have experienced the greatest climate change in recent decades. Predicted changes, including a continuing rise in temperature and precipitation and a reduction in snow cover, are expected to have a large impact on Arctic life. Large numbers of birds breed on the Arctic tundra, and many of these, such as shorebirds and passerines, feed on arthropods. Their chicks depend on a short insect population outburst characteristic of Arctic areas. To predict the consequences of climate change for reproduction in these birds, insight into arthropod phenology is essential. We investigated weather-related and seasonal patterns in abundance of surface-active arthropods during four years in the tundra of NW Taimyr, Siberia. The resulting statistical models were used to hindcast arthropod abundance on the basis of a 33-year weather dataset collected in the same area. Daily insect abundance was correlated closely with date, temperature, and, in some years, with wind and precipitation. An additional correlation with the number of degree-days accumulated after 1 June suggests that the pool of potential arthropod recruits is depleted in the course of the summer. The amplitude of short-term, weather-induced variation was as large as that of the seasonal variation. The hindcasted dates of peak arthropod abundance advanced during the study period, occurring seven days earlier in 2003 than in 1973. The timing of the period during which birds have a reasonable probability of finding enough food to grow has changed as well, with the highest probabilities now occurring at earlier dates. At the same time, the overall length of the period with probabilities of finding enough food has remained unchanged. The result is an advancement of the optimal breeding date for breeding birds. To take advantage of the new optimal breeding time, Arctic shorebirds and passerines must advance the start of breeding, and this change could affect the entire migratory schedule. Because our analyses are based on a single site, we cannot conclude that this is a general pattern for the entire Arctic. To investigate the generality of this pattern, our approach should be applied at other sites too.
Contrasting trends in two Black-tailed Godwit populations: a review of causes and recommendations
Gill, J.A. ; Langston, R.H.W. ; Alves, J.A. ; Atkinson, P.W. ; Bocher, P. ; Cidraes Vieira, N. ; Crockford, N.J. ; Gélinaud, G. ; Groen, N. ; Gunnarsson, T.G. ; Hayhow, B. ; Hooijmeijer, J. ; Kentie, R. ; Kleijn, D. ; Lourenço, P.M. ; Masero, J.A. ; Meunier, F. ; Potts, P.M. ; Roodbergen, M. ; Schekkerman, H. ; Schröder, J. ; Wymenga, E. ; Piersma, T. - \ 2007
Bulletin / Wader Study Group 114 (2007). - ISSN 0260-3799 - p. 43 - 50.
In recent decades, the West European population of Black-tailed Godwits, Limosa limosa limosa, has declined in size at a quite alarming rate, while the Icelandic population, L. l. islandica, has undergone a rapid increase in population size. These two populations have been the subject of a great deal of research, much of which has been focused on understanding the causes and consequences of the contrasting population trends. In 2007, a workshop was held during the annual conference of the International Wader Study Group at La Rochelle, France, with the aims of identifying the likely causes of the population changes and providing recommendations for future actions to improve the conservation of both populations. The available evidence strongly suggests that changes in productivity as a consequence of agricultural intensification are the most likely driver of the decline in L. l. limosa, although the concentration of much of the population in just a few sites in winter and spring is likely to exacerbate their vulnerability to future habitat changes. Agricultural and climatic changes are implicated in the expansion of L. l. islandica, and the availability of both intertidal mudflats and wet grasslands as foraging habitats appears to be very important across much of the winter range of this population. A series of recommendations for actions to conserve both populations are provided, including improving agricultural land management and protecting key passage and winter sites and habitats.
Abundance of invertebrates and foraging success of black-tailed godwit Limosa limosa chicks in relation to agricultural grassland management
Schekkerman, H. ; Beintema, A.J. - \ 2007
Ardea 95 (2007)1. - ISSN 0373-2266 - p. 39 - 54.
farmland bird populations - agri-environment schemes - breeding success - vanellus-vanellus - meadow birds - responses - auchenorhyncha - biodiversity - predation - britain
Effects of agricultural intensification on availability of grassland invertebrates as food for chicks of the declining Black-tailed Godwit Limosa limosa were studied in The Netherlands. Invertebrates were sampled with photo-eclectors in wet grasslands used for intensive dairy farming (high fertiliser input, 2¿3 cuts starting early to mid-May) and in a meadowbird reserve (moderate fertiliser input, one cut in mid-June). Invertebrates were slightly more abundant in reserve than in agricultural fields before the first cut of the latter. In the 4¿6 weeks between the first cut of agricultural fields and that of reserve fields, invertebrates were much more abundant on reserve fields. Most godwit chicks were raised during this period. Mean size of arthropods was similar under the two management regimes, but large Coleoptera were more abundant in agricultural fields early in the season. In a foraging experiment, captive-raised godwit chicks ingested 31% fewer prey per unit time when foraging in cut agricultural grasslands than in uncut reserve fields, a difference large enough to compromise chick growth and survival. Wild broods strongly selected to stay in reserve fields, especially after agricultural fields had been cut, and travelled towards reserve fields over distances up to more than 0.5 km. Preference for reserve grasslands declined from early June onwards. We conlcude that postponing mowing dates, in reserves or on farmland by means of agri-environment initiatives, improves feeding and survival conditions for godwit chicks and other insectivores feeding in the grassland sward, in addition to its beneficial effect on hatching success.
De voedselsituatie voor gruttokuikens bij agrarisch mozaïekbeheer
Kleijn, D. ; Dimmers, W.J. ; Kats, R.J.M. van; Melman, T.C.P. ; Schekkerman, H. - \ 2007
Wageningen : Alterra (Alterra-rapport 1487) - 50
limosa limosa - voedering - natuurbescherming - agrarische bedrijfsvoering - graslandbeheer - overleving - ruimtelijke variatie - nederland - voedingsecologie - weidevogels - agrarisch natuurbeheer - feeding - nature conservation - farm management - grassland management - survival - spatial variation - netherlands - feeding ecology - grassland birds - agri-environment schemes
Mozaiekbeheer blijkt niet te leiden tot de gewenste verhoging van overleving bij grutto's. In dit rapport is onderzocht wat de vegetatiesamenstelling van de graslanden is en wat het aanbod aan ongewervelden voor weidevogels in die percelen is. Het blijkt dat kruidenrijke, schrale percelen een goede vegetatiestructuur gedurende de gehele kuikenperiode hebben; terwijl de ongewervelden in mei hoger is dan in juni
Parental role division predicts avian preen wax cycles
Reneerkens, J. ; Almeida, J.B. ; Lank, D.B. ; Jukema, J. ; Lanctot, R.B. ; Morrison, R.I.G. ; Rijpstra, W.I.C. ; Schamel, D. ; Schekkerman, H. ; Sinninghe Damste, J.S. ; Tomkovich, P.S. ; Tracy, D.M. ; Tulp, I.Y.M. ; Piersma, T. - \ 2007
Ibis 149 (2007)4. - ISSN 0019-1019 - p. 721 - 729.
knot calidris-canutus - red knots - social-organization - gland waxes - sandpipers - scolopacidae - evolution - switch - oil - sex
Previous studies have shown that preen wax composition in some sandpipers shifts from the usual monoesters to diesters during the breeding season, possibly to reduce the ability of mammalian predators to find nests using olfactory cues. To investigate further the relationship between incubation and wax secretion, we examined seven sandpiper species with different incubation patterns (species in which both sexes incubate, in which only males incubate and in which only females incubate). During the breeding period, diester preen wax was secreted almost exclusively by the incubating sex in species with uniparental incubation, and by both sexes in species with biparental incubation. These findings suggest that diester preen waxes have a function that is directly related to incubation. Unexpectedly, in female-incubating Curlew Sandpiper Calidris ferruginea and Buff-breasted Sandpiper Tryngites subruficollis, some males also secreted diester preen waxes during the breeding period. This suggests that some males may in fact incubate, that these waxes may be a remnant from their evolutionary past when both sexes incubated, or that males need to be olfactorally cryptic because they are involved in the making of nest scrapes. The seasonal pattern of preen wax composition was also studied in captive male, female and female-mimicking male (`faeder¿) Ruff Philomachus pugnax. Captive female Ruff changed preen wax composition from monoesters to diesters in the spring despite the fact that no incubation took place. This suggests that circannual rhythms rather than actual incubation behaviour may trigger the shift to diester waxes. All captive male Ruff, including the faeders, continued to secrete monoesters, supporting the hypothesis that only the incubating sex secretes diesters.
Growth and energetics of a small shorebird species in a cold environment: the little stint Calidris minuta on the Taimyr Peninsulam Siberia
Tjorve, K.M.C. ; Schekkerman, H. ; Tulp, I.Y.M. ; Underhill, L.G. ; Leeuw, J.J. de; Visser, G.H. - \ 2007
Journal of Avian Biology 38 (2007)5. - ISSN 0908-8857 - p. 552 - 563.
labeled water method - energy-requirements - breeding biology - body-size - chicks - birds - validation - temperature - maturation - sandpiper
The little stint Calidris minuta is one of the smallest shorebird species breeding in the Arctic (weighing 4.3 g on hatching). Their chicks are small and have a high surface area-to-volume ratio. We determined prefledging growth, energy expenditure and time budgets for little stint chicks in northwestern Taimyr, Siberia. A modified power curve was introduced to model the relationship between daily energy expenditure and body mass. Total metabolisable energy, TME, over the 15-d prefledging period was 107% greater than the allometric prediction for a bird the size of a little stint. Their growth rate coefficient was 14% greater than the prediction for a bird their size. The growth of young chicks was reduced in cool weather, possibly due to a reduction in foraging time in order to be brooded and reduced food availability which impact foraging efficiency. We did not detect weather effects on energy expenditure of chicks, but lack of temperature variation during energy expenditure measurements may have prevented this. In sum, both growth rate coefficient and energy expenditure of little stint chicks were greater than predicted and this is similar to that observed in other arctic shorebird species.
Assessing the development of shorebird eggs using the flotation method: species - specific and generalized regression models
Liebezeit, J.R. ; Smith, P.A. ; Lanctot, R.B. ; Schekkerman, H. ; Tulp, I.Y.M. ; Kendall, S.J. ; Tracy, D.M. ; Rodrigues, R.J. ; Meltofte, H. ; Robinson, J.A. ; Gratto-Trevor, C. ; Mccaffery, B.J. ; Morse, J. ; Zack, S.W. - \ 2007
Condor 109 (2007)1. - ISSN 0010-5422 - p. 32 - 47.
estimate incubation stage - nest survival - date - age - period
We modeled the relationship between egg flotation and age of a developing embryo for 24 species of shorebirds. For 21 species, we used regression analyses to estimate hatching date by modeling egg angle and float height, measured as continuous variables, against embryo age. For eggs early in incubation, we used linear regression analyses to predict hatching date from logit-transformed egg angles only. For late incubation, we used multiple regression analyses to predict hatching date from both egg angles and float heights. In 30 of 36 cases, these equations estimated hatching date to within four days of the true hatching date for each species. After controlling for incubation duration and egg size, flotation patterns did not differ between shorebirds grouped by mass (¿100 g or
Voedselsituatie voor gruttokuikens bij verschillende graslandtypen
Kleijn, D. ; Kats, R.J.M. van; Melman, T.C.P. ; Schekkerman, H. - \ 2006
limosa limosa - weidevogels - natuurbeheer - graslanden - bodems van waterrijke gebieden - agrarisch natuurbeheer - grassland birds - nature management - grasslands - wetland soils - agri-environment schemes
Weidevogels komen vooral voor op natte graslanden die in het verleden extensief gebruikt werden. Daardoor waren de meeste weidevogels al uitgebroed voordat de eerste agrarische werkzaamheden plaatsvonden. Daarnaast stelde enerzijds de beperkte snelheid waarmee landbouwactiviteiten werden uitgevoerd en anderzijds de lage veedichtheden weidevogelparen met kuikens in staat om machines en vee te ontwijken. Doordat de belangrijkste perioden waarin door landbouw en weidevogels gebruik werd gemaakt van landbouwpercelen gescheiden waren in de tijd, gingen landbouw en hoge dichtheden weidevogels uitstekend samen. Intensivering van de landbouw heeft geleid tot een vervroeging van landbouwkundige activiteiten. Momenteel worden kleine percentages van het oppervlak natte graslanden begraasd of laat gemaaid als gevolg van beheersovereenkomsten Het overgrote deel wordt echter geheel gemaaid in de loop van mei. Hierdoor vinden landbouwkundige activiteiten plaats gedurende het broedseizoen van de weidevogels en dit kan verklaren waarom de meeste soorten weidevogels sterk achteruit zijn gegaan gedurende de laatste decennia.
Predatie bij weidevogels : op zoek naar de mogelijke effecten van predatie op de weidevogelstand, uitgebreide samenvatting
Teunissen, W. ; Schekkerman, H. ; Willems, F. - \ 2006
Beek-Ubbergen : SOVON Vogelonderzoek Nederland (Alterra-rapport 1292 samenvatting) - 24
vogels - populaties - predatie - predatoren - nestelen - nederland - weidevogels - birds - populations - predation - predators - nesting - netherlands - grassland birds
Weidevogels zijn in de laatste decennia sterk in aantal achteruitgegaan. Dit proces lijkt zich de laatste jaren zelfs nog te versnellen. Oorzaken voor deze negatieve ontwikkeling worden vooral gezocht in verlies van geschikt broedgebied voor weidevogels en de voortgaande intensivering van het agrarisch landgebruik. Daarnaast wordt predatie van legsels en kuikens de laatste jaren steeds vaker als probleem genoemd; volgens sommigen is het zelfs de hoofdoorzaak van de afnemende weidevogelpopulaties. Meningen daarover lopen echter zeer uiteen. SOVON, Alterra en Landschapsbeheer Nederland hebben daarom gezamenlijk een grootschalig onderzoek uitgevoerd naar het effect van predatie op de weidevogelpopulaties
NOU seminar: Birds of agricultural areas / Nederlandse Ornithologische Unie: themadag 'vogels van het agrarisch gebied'
Bijlsma, R. ; Kleijn, D. ; Koffijberg, K. ; Teunissen, W. ; Kragten, S. ; Oosterveld, E. ; Schekkerman, H. ; Vickery, J. - \ 2006
Limosa 79 (2006)2. - ISSN 0024-3620 - p. 71 - 76.
vogels - wildbescherming - populatiedichtheid - bedreigde soorten - birds - population density - wildlife conservation - endangered species
Het gaat bijzonder slecht met veel vogels van het agrarisch gebied. Zowel weidevogels als akkervogels staan zwaar onder druk. Vogelbescherming Nederland, SOVON en de Ornothologische Unie hielden een studiedag in Leiden (maart 2006). Dit artikel doet verslag van (onderzoeks)bevindingen vanuit CML, SOVON, Alterra, Radboud Universiteit en Altenburg & Wymenga
Een analyse van de mogelijke gevolgen van de aanleg van IJburg tweede fase voor watervogels in de SBZ IJmeer
Schekkerman, H. ; Eerden, M.E. van; Rijn, S. van; Roos, M. - \ 2006
Wageningen : Alterra (Alterra-rapport 1363) - 95
vogels - milieueffect - wildbescherming - stedelijke planning - nederland - amsterdam - birds - environmental impact - wildlife conservation - urban planning - netherlands - amsterdam
De gemeente Amsterdam heeft vergevorderde plannen om in het IJmeer, grenzend aan het Vogelrichtlijngebied (SBZ, Natura 2000 gebied) IJmeer, de tweede fase van de wijk IJburg te realiseren. In dit rapport wordt (1) beschreven welke specifieke waarden van het IJmeer volgens de Vogelrichtlijn dienen te worden beschermd, (2) verkend welke invloed IJburg II op deze waarden zal hebben en of daarbij sprake is van significante gevolgen in het kader van de Vogelrichtlijn, en (3) aangegeven welke mitigerende maatregelen de verstorende effecten van IJburg II kunnen voorkomen. Het rapport zal mede de basis vormen onder een nieuwe versie van het bestemmingsplan voor IJburg II, die vervolgens aan een `passende beoordeling¿ in het kader van de NB-wet 1998 zal worden onderworpen
Verdeling van de broedinspanning bij kieviten
Jongbloed, F. ; Schekkerman, H. ; Teunissen, W. - \ 2006
Limosa 79 (2006)2. - ISSN 0024-3620 - p. 63 - 70.
vanellus vanellus - vanellus - broedduur - broedvogels - weidevogels - vanellus vanellus - vanellus - incubation duration - breeding birds - grassland birds
Kievitpartners verdelen hun broedactiviteiten, maar hoe zit dit bij kievitmannetjes? Alhoewel kievitmannetjes als monogaam worden beschouwd, zijn er kievitmannetjes die er meerdere partners op na houden. Na zonsondergang blijken de broedactiviteiten van het mannetje af te nemen. Na zonsopkomst nemen die activiteiten weer toe. Een verklaring voor dit verschil is er echter niet. Verslag van onderzoek vanuit Alterra en SOVON
Broedsucces van grutto's bij mozaïekbeheer in "Nederland Gruttoland"
Schekkerman, H. ; Teunissen, W. ; Oosterveld, E. - \ 2006
Limosa 79 (2006)2. - ISSN 0024-3620 - p. 75 - 75.
Modelling the flyway of arctic breeding shorebirds; parameter estimation and sensitivity analysis
Ens, B.J. ; Schekkerman, H. ; Tulp, I.Y.M. ; Bauer, S. ; Klaassen, M. - \ 2006
Wageningen : Alterra (NIOO-rapport 2006-01) - 119
zeevogels - kusten - migratie - modellen - vliegen - energiekosten van activiteiten - predatie - calidris - oevers - sea birds - coasts - migration - models - flight - energy cost of activities - predation - calidris - shores
This report describes the derivation of parameter estimates for the model DYNAMIG for an arctic breeding shorebird, the Knot. DYNAMIG predicts the optimal spring migration of birds, like shorebirds and geese, that depend of a chain of discrete sites, to travel between their breeding grounds and their wintering grounds. An important parameter is the terminal reward, which describes the fitness consequences of arriving with a particular body condition at a particular time on the breeding grounds. We derived the terminal reward from field studies in Siberia carried out as part of this project. Other parameter values, like flight costs, maintenance metabolism and predation risk were derived from the literature. Predictions on aspects of the migration schedule with the parameterized model were partly correct and partly wrong. Suggestions are made how to remedy the discrepancies. An interesting prediction of the model that requires testing is that Knots breeding in Canada migrate via Iceland, whereas Knots breeding on Greenland migrate via Norway. A sensitivity analysis indicated that this prediction was quite robust.
Losses in lapwing and godwit reproduction: predation and other causes
Schekkerman, H. ; Teunissen, W. - \ 2006
In: Losses in lapwing and godwit reproduction: predation and other causes. - Leeuwarden : Van Hall Larenstein - p. 34 - 35.
Predatie: een probleem erbij voor onze weidevogels?
Schekkerman, H. ; Teunissen, W.A. - \ 2006
De Levende Natuur 107 (2006)3. - ISSN 0024-1520 - p. 121 - 125.
vogels - predatie - voortplanting - monitoring - weidevogels - birds - predation - reproduction - grassland birds
De recente ontwikkelingen ten aanzien van weidevogels en faunabeleid vormden de aanleiding voor een aantal natuurorganisaties en overheden voor een grootschalig onderzoek naar predatie. Hoofdlijnen uit het onderzoek van SOVON en Alterra worden in dit artikel gegeven
Time allocation between feeding and incubation in uniparental arctic-breeding shorebirds: energy reserves provide leeway in a tight schedule
Tulp, I.Y.M. ; Schekkerman, H. - \ 2006
Journal of Avian Biology 37 (2006)3. - ISSN 0908-8857 - p. 207 - 218.
sandpipers - clutch - attentiveness - expenditure
Birds with uniparental incubation may face a time allocation problem between incubation and feeding. Eggs need regular warming to hatch successfully, but the parent must leave the nest to feed and safeguard its own survival. Time allocation during incubation is likely to depend on factors influencing egg cooling rates, parental energy requirements and feeding intake rate. How this allocation problem is resolved was subject of this study on arctic-breeding shorebirds. We compared incubation rhythms between four uniparental shorebird species differing in size and expected to find both species differences and weather effects on the organisation of incubation. Attentive behaviour and responses to variation in weather showed a remarkable consistency across species. All species alternated feeding bouts (recesses) with brooding bouts throughout the day. Recesses were concentrated in the warmer parts of the day, while recess duration showed little diurnal variation. Despite continuous daylight, a pronounced day-night rhythmicity was apparent. The four species in this study spent a similar proportion (13-19%) of the time off their nest. After correction for weather effects, the number of recesses was largest in the smallest species, while recess duration was longest in the largest species. Total recess time per day increased on cold days through an increase of mean recess length, while the number of recesses decreased. Comparing our observations to predictions derived from criteria that birds might use to organise their attentive behaviour, showed that the limits are set by parental requirements, while the energy stores of adults provide some leeway for short-term adjustments to environmental variability. If breeding birds trade off feeding time against incubation time, energy stores are expected to be influenced by weather. We expected uniparental species to be more likely to show weather effects on condition than biparentals, as in the latter 'off duty' time is much larger and independent of weather. This prediction was tested by comparing energy stores in two uniparental species and a biparental congener. While body mass of uniparental incubators decreased after a period with low temperatures, body mass of the biparental species did not.
Weidevogels en Predatie
Schekkerman, H. - \ 2005
Texel : Alterra - 3
predatie - weidevogels - agrarisch natuurbeheer - natuurbeleid - maatregelen - wetenschappelijk onderzoek - predation - grassland birds - agri-environment schemes - nature conservation policy - measures - scientific research
Er is in Nederland een toenemende bezorgdheid toenemende predatiedruk op weidevogels. Die discussie is relevant in relatie tot de nieuwe Flora- en Faunawet (faunabeheerplannen, ontheffingen voor afschot van predatoren, vrijstelling vos), maar ook in relatie tot de effectiviteit van bestaande instrumenten voor (agrarisch) weidevogelbeheer. In bepaalde regio’s loopt de discussie over mogelijke vervolging van predatoren hoog op, veelal zonder dat goed feitenmateriaal aanwezig is om beleid op te baseren. De hoofdvragen daarbij zijn: (1) Hoe vaak komt predatie op weidevogellegsel en –kuikens voor, (2) welke predators zijn er bij betrokken, (3) welke factoren hebben invloed op de omvang en/of het effect van de predatie, en (4) is de huidige predatiedruk een probleem voor de ontwikkeling van weidevogelpopulaties, ook in verhouding tot andere verliesoorzaken? Het doel van dit onderzoek is om bovengenoemde vragen te beantwoorden op grond van systematisch verzameld feitenmateriaal
Broedsucces van grutto's bij agrarisch mozaïekbeheer in "Nederland gruttoland"
Schekkerman, H. ; Teunissen, W. ; Oosterveld, E. - \ 2005
Wageningen : Alterra (Alterra-rapport 1291) - 153
limosa limosa - vogels - natuurbescherming - uitbroeden - predatie - nederland - agrarisch natuurbeheer - limosa limosa - birds - nature conservation - hatching - predation - netherlands - agri-environment schemes
In het kader van het project `Nederland Gruttoland¿ is in zes gebieden in Nederland in 2003-2005 een nieuwe, experimentele vorm van agrarisch natuurbeheer (`mozaïekbeheer¿), speciaal gericht op de grutto Limosa limosa in de praktijk getest. Dit rapport geeft de resultaten van onderzoek naar de effectiviteit van de beheersmaatregelen voor het broedsucces van de grutto¿s. Weliswaar werd een hoger broedsucces gemeten in de mozaïek-gebieden dan in referentiegebieden, maar dat kwam geheel tot stand door een hoger uitkomstsucces van nesten. De overleving van gruttokuikens was in de mozaïeken niet hoger, vermoedelijk doordat het aanbod van voor kuikens geschikt grasland niet verschilde tussen mozaïeken en referenties. Dat was o.a. een gevolg van regenachtig weer in mei, waardoor ook in de referenties de boeren de eerste snede uitstelden. Los van het onderscheid mozaïek-referentie werd wel een positief verband gevonden tussen het aanbod van `kuikenland¿ en de kuiken-overleving. Over de gehele linie waren kuikenoverleving en broedsucces te laag om de populatie zichzelf te laten vervangen. Predatie was de belangrijkste doodsoorzaak van kuikens en vormt, mogelijk in combinatie met veranderingen in de kwaliteit van het `kuikenland¿, een additionele factor die maakt dat tegenwoordig een grotere beheersinspanning nodig is om een voldoende hoog broedsucces te bereiken dan enkele decennia geleden.
Predatie bij weidevogels; op zoek naar de mogelijke effecten van predatie op de weidevogelstand
Teunissen, W. ; Schekkerman, H. ; Willems, F. - \ 2005
Beek-Ubbergen : Sovon (Alterra-document 1292) - 172
predatie - nestelen - voortplanting - predatoren - nederland - weidevogels - predation - nesting - reproduction - predators - netherlands - grassland birds
Gezamenlijk onderzoek van SOVON, Alterra en Landschapsbeheer Nederland naar natuurlijke schade aan legsels en kuikens van weidevogels. Door plaatsing van videocamera's en temperatuurloggers werd aanvullende informatie verkregen, naast het vele veldverk verricht door boeren en vrijwilligers
Declining Biodiversity in Agricultural Landscapes and the Effectiveness of Agri-environment Schemes
Berendse, F. ; Chamberlain, D. ; Kleijn, D. ; Schekkerman, H. - \ 2004
Ambio 33 (2004)8. - ISSN 0044-7447 - p. 499 - 502.
birds - england - intensification - countryside - grasslands - britain
Agricultural intensification, greatly accelerated as a result of the EU Common Agricultural Policy (CAP), has led to rastic reductions in the populations of many wild plant and animal species that used to be characteristic of farmland. In 1992, the EU provided the member states with its Agri-environment Regulation 2078/92 to help member states reverse these developments by means of agri-environment schemes. The question is: will the implementation of these schemes be sufficient to restore the biological diversity on farmland? Most studies that have examined the effectiveness of agri-environment schemes have focussed on farmland birds in Great Britain and The Netherlands. So far, the positive effects appear to be limited. Continuous evaluation and adaptation of these schemes is needed to enable the biodiversity on farmland to recover from the EU's former policy.
Studies on breeding shorebirds at Medusa Bay, Taimyr, in Summer 2002
Schekkerman, H. ; Tulp, I.Y.M. ; Calf, K.M. ; Leeuw, J.J. de - \ 2004
Wageningen : Alterra (Alterra-rapport 922) - 101
vogels - nestelen - voortplanting - monitoring - arctische gebieden - predatie - geleedpotigen - rusland - waadvogels - birds - nesting - reproduction - arctic regions - predation - arthropods - russia - waders
In the summer of 2002 a combined Dutch-Russian expedition took place to the Willem Barentz field station at Medusa Bay near Dikson in north-western Taimyr, Russia. The expedition was organised by Alterra and the Agricultural Department of the Dutch Embassy in Moscow. Research questions addressed by the Alterra team and basic results obtained during the 2002 season are presented in this report. More elaborate analyses and discussion of the data will be made elsewhere. Where useful, results are compared with data collected in 2000 and 2001. Subjects of study generally concerned breeding biology of arctic breeding shorebirds, especially with respect to timing of breeding.
Evaluatie agrarisch natuurbeheer: effecten op weidevogeldichtheden
Willems, F. ; Breeuwer, A.J.G. ; Foppen, R.P.B. ; Teunissen, W. ; Schekkerman, H. ; Goedhart, P.W. ; Kleijn, D. ; Berendse, F. - \ 2004
Beek-Ubbergen : Sovon (SOVON onderzoekrapport 2004/02) - 29
evaluatie - nederland - natuurbescherming - weidevogels - agrarisch natuurbeheer - nature conservation - evaluation - netherlands - grassland birds - agri-environment schemes
Het huidige beleid om weidevogels te beschermen is niet erg effectief. Dit blijkt uit een omvangrijk onderzoek van Wageningen Universiteit, SOVON en Alterra. Het aantal grutto's neemt niet toe en de populatie kieviten gaat zelfs achteruit. De onderzoekers concluderen echter niet dat boeren moeten stoppen met de beheersovereenkomsten. Het lijkt er juist op dat er meer moet worden gedaan
Base line studies North Sea wind farms : strategy of approach for flying birds
Krijgsveld, K.L. ; Lieshout, S.M.J. ; Schekkerman, H. ; Lensink, Rick ; Poot, M.J.M. ; Dirksen, S. - \ 2003
Alterra - 54
wind power - adverse effects - birds - marine areas - north sea - windenergie - nadelige gevolgen - vogels - mariene gebieden - noordzee
The Dutch government has granted ‘Noordzeewind’ (Nuon Renewable Energy Projects and Shell Wind Energy) the possibility to build a wind farm consisting of 36 wind turbines off the coast of the Netherlands, near Egmond. This project serves to evaluate the economical, technical, ecological and social effects of offshore wind farms in general. To gather the knowledge which will result from this project, a Monitoring and Evaluation Program (MEP) has been developed. Bureau Waardenburg and Alterra in cooperation have been commissioned by RIKZ to execute the base line study of effects on flight paths, flight altitudes and flux of migratory and non-migratory birds.
High daily energy expenditure of incubating shorebirds on High Arctic tundra: a circumpolar study
Piersma, T. ; Lindström, C. ; Drent, R.H. ; Tulp, I. ; Jukema, J. ; Morrison, R.I.G. ; Reneerkens, J. ; Schekkerman, H. ; Visser, G.H. - \ 2003
Functional Ecology (2003)3. - ISSN 0269-8463 - p. 356 - 362.
evaporative water-loss - energetics - animals - errors - birds - costs - knot
¿ Given the allometric scaling of thermoregulatory capacity in birds, and the cold and exposed Arctic environment, it was predicted that Arctic-breeding shorebirds should incur high costs during incubation. Using doubly labelled water (DLW), daily energy expenditure (DEE) during incubation was measured in eight shorebird species weighing between 29 and 142 g at various sites in the Eurasian and Canadian High Arctic. The results are compared with a compilation of similar data for birds at lower latitudes. ¿ There was a significant positive correlation between species average DEE and body mass (DEE (kJ day-1) = 28?12 BM (g)0?524, r2 = 0?90). The slopes of the allometric regression lines for DEE on body mass of tundra-breeding birds and lower latitude species (a sample mostly of passerines but including several shorebirds) are similar (0?548 vs 0?545). DEE is about 50% higher in birds on the tundra than in temperate breeding areas. ¿ Data for radiomarked Red Knots for which the time budgets during DLW measurements were known, indicated that foraging away from the nest on open tundra is almost twice as costly as incubating a four-egg clutch. ¿ During the incubation phase in the High Arctic, tundra-breeding shorebirds appear to incur among the highest DEE levels of any time of the year. The rates of energy expenditure measured here are among the highest reported in the literature so far, reaching inferred ceilings of sustainable energy turnover rates.
Mechanisms promoting higher growth rate in arctic than in temperate shorebirds
Schekkerman, H. ; Tulp, I.Y.M. ; Piersma, T. ; Visser, G.H. - \ 2003
Oecologia (2003)3. - ISSN 0029-8549 - p. 332 - 342.
snow-goose goslings - energy-requirements - body-temperature - birds - chicks - energetics - homeothermy - metabolism - behavior - weather
We compared prefledging growth, energy expenditure, and time budgets in the arctic-breeding red knot (Calidris canutus) to those in temperate shorebirds, to investigate how arctic chicks achieve a high growth rate despite energetic difficulties associated with precocial development in a cold climate. Growth rate of knot chicks was very high compared to other, mainly temperate, shorebirds of their size, but strongly correlated with weather-induced and seasonal variation in availability of invertebrate prey. Red knot chicks sought less parental brooding and foraged more at the same mass and temperature than chicks of three temperate shorebird species studied in The Netherlands. Fast growth and high muscular activity in the cold tundra environment led to high energy expenditure, as measured using doubly labelled water: total metabolised energy over the 18-day prefledging period was 89% above an allometric prediction, and among the highest values reported for birds. A comparative simulation model based on our observations and data for temperate shorebird chicks showed that several factors combine to enable red knots to meet these high energy requirements: (1) the greater cold-hardiness of red knot chicks increases time available for foraging; (2) their fast growth further shortens the period in which chicks depend on brooding; and (3) the 24-h daylight increases potential foraging time, though knots apparently did not make full use of this. These mechanisms buffer the loss of foraging time due to increased need for brooding at arctic temperatures, but not enough to satisfy the high energy requirements without invoking (4) a higher foraging intake rate as an explanation. Since surface-active arthropods were not more abundant in our arctic study site than in a temperate grassland, this may be due to easier detection or capture of prey in the tundra. The model also suggested that the cold-hardiness of red knot chicks is critical in allowing them sufficient feeding time during the first week of life. Chicks hatched just after the peak of prey abundance in mid-July, but their food requirements were maximal at older ages, when arthropods were already declining. Snow cover early in the season prevented a better temporal match between chick energy requirements and food availability, and this may enforce selection for rapid growth.
Vogels van het boerenland: regionale verschillen
Teunissen, W.A. ; Schekkerman, H. - \ 2002
De Levende Natuur (2002). - ISSN 0024-1520
vogels - biogeografie - fauna - nederland - weidevogels - agrarisch natuurbeheer - ecologie - landbouw - ornithologie - birds - biogeography - netherlands - grassland birds
Resultaten van het nationaal weidevogelnetwerk, waarin samenwerken CBS, SOVON, Vogelonderzoek Nederland en de provincies, met subsidies van LNV
Vluchtstroken voor gruttogezinnen; werken ze?
Schekkerman, H. - \ 2002
Nieuws van Waterland 5 (2002). - p. 10 - 11.
agrarisch natuurbeheer - ecologie - fauna - grasland - grutto - landbouw - ornithologie - weidebouw - weidevogels - Noord-Holland - Waterland
Treedt er stuwing op tijdens nachtelijke seizoenstrek van vogels over de Afsluitdijk? Veldonderzoek naar hoogteverdelingen en horizontale gradiënten
Poot, M.J.M. ; Winden, J. van der; Schekkerman, H. ; Lieshout, S.M.J. van; Dirksen, S. - \ 2002
Culemborg : Bureau Waardenburg (Rapport 02-005) - 75 p.
ecologie - fauna - ornithologie - vogeltrek - Afsluitdijk - IJsselmeer
Perspectief voor de grauwe gans als broedvogel in het Deltagebied bij verschillende beheermaatregelen
Ebbinge, B.S. ; Klok, T.C. ; Schekkerman, H. ; Turnhout, C. van; Voslamber, B. ; Willems, F. - \ 2002
De Levende Natuur (2002). - ISSN 0024-1520
anser - ganzen - begrazing - weiden - agrarische bedrijfsvoering - oogstverliezen - schadelijke dieren - zuid-holland - zeeland - zuidwest-nederland - broedvogels - ecologie - natuurbeheer - ornithologie - geese - grazing - pastures - farm management - yield losses - noxious animals - south-west netherlands
Onderzoek in opdracht van Zeeland, Zuid-Holland, Noord-Brabant, Natuurmonumenten en Staatsbosbeheer. Onderzocht is met welke maatregelen de overlast van begrazing door ganzen voor boeren te beperken is
Vogelkundige waarden van de polder Zeevang, 1996-2001; een evaluatie in het kader van de EG-Vogelrichtlijn
Schekkerman, H. ; Beintema, A.J. - \ 2002
Wageningen : Alterra (Alterra-rapport 450) - 29
anas - vogels - richtlijnen (directives) - bescherming - monitoring - nederland - waadvogels - ecologie - fauna - ornithologie - trekvogels - watervogels - Noord-Holland - birds - directives - protection - netherlands - waders
In dit rapport worden de meest recente gegevens over het voorkomen van trekkende watervogelsoorten in de polder de Zeevang en omgeving (Noord-Holland) samengevat. Op grond van de drempeloverschrijdende aantallen overwinterende smienten (Anas penelope)wordt geadviseerd de Zeevang aan te wijzen als speciale beschermingszone onder de EG-Vogelrichtlijn.
Mogelijke gevolgen van de tweede fase van IJburg voor watervogels in de speciale beschermingszone IJmeer; een beoordeling in het kader van de EG-Vogelrichtlijn
Schekkerman, H. ; Beintema, A.J. - \ 2002
Wageningen : Alterra (Alterra-rapport 431) - 45
vogels - water - richtlijnen (directives) - bescherming - stadsontwikkeling - nederland - amsterdam - ecologie - fauna - ornithologie - watervogels - Noord-Holland - birds - directives - protection - urban development - netherlands
In dit rapport wordt een beoordeling gemaakt van de mogelijke gevolgen die de aanleg van de tweede fase van IJburg kan hebben op de vogelkundige waarden van de onder de EG-Vogelrichtlijn aangewezen Speciale Beschermingszone IJmeer. Geconcludeerd wordtdat voor de meeste relevante soorten watervogels een neutraal tot licht positief effect te verwachten valt, maar dat er twee aandachtspunten zijn die mogelijk kunnen leiden tot negatieve effecten: sterfte van driehoeksmosselen door sediment dat vrijkomt bij de opspuiting, en verstoring van watervogels door (water)recreatie. Verdere studies zouden moeten uitwijzen in hoeverre dit daadwerkelijk tot problemen leidt.
Body mass patterns of little stints at different latitudes during incubation and chick-rearing
Tulp, I. ; Schekkerman, H. ; Chylarecki, P. ; Tomkovich, P. ; Soloviev, M. ; Bruinzeel, L. ; Dijk, K. van; Hildén, O. ; Hötker, H. ; Kania, W. ; Roomen, M. van; Sikora, A. ; Summers, R. - \ 2002
Ibis 144 (2002)1. - ISSN 0019-1019 - p. 122 - 134.
fauna - broedgedrag - ecologie - fauna - ornithologie - poolgebied - steltlopers - strandloper - Europa - Rusland - Noorwegen
Due to the 'double-clutch' mating system found in the arctic-breeding Little Stint Calidris minuta, each parent cafes for a clutch and brood alone. The resulting constraint on feeding time, combined with the cold climate and a small body size, may cause energetic bottlenecks. Based on the notion that mass stores in birds serve as an 'insurance' for transient periods of negative energy balance, but entail certain costs as well, body mass may vary in relation to climatic conditions and stage of the breeding cycle. We studied body mass in Little Stints in relation to breeding stage and geographical location, during 17 expeditions to 12 sites in the Eurasian Arctic, ranging from north Norway to north-east Taimyr. Body mass was higher during incubation than during chick-rearing. Structural size, as estimated by wing length, increased with latitude. This was probably caused by relatively more females (the larger sex) incubating further north, possibly after leaving a first clutch to be incubated by a male further south. Before and after correction for structural size, body mass was strongly related to latitude during both incubation and chick-rearing. In analogy to a similar geographical pattern in overwintering shorebirds, we interpret the large energy stores of breeding Little Stints as an insurance against periods of cold weather which are a regular feature of arctic summers. Climate data showed that the risk of encountering cold spells lasting several days increases with latitude over the species' breeding range, and is larger in June than in July. Maintaining these stores is therefore less necessary at southern sites and during the chick-rearing period than in the incubation period. When guarding chicks, feeding time is less constrained than during incubation, temperatures tend to be higher than in the incubation period, reducing energy expenditure, and the availability of insect prey reaches a seasonal maximum. However, the alternative interpretation that the chick-tending period is more energetically stressful than the incubation period, resulting in a negative energy balance for the parent, could not be rejected on the present evidence.
Nadere toetsing van aanwijzing en begrenzing van negen Vogelrichtlijngebieden
Beintema, A.J. ; Schekkerman, H. - \ 2001
Wageningen : Alterra (Alterra-rapport 328) - 61
vogels - conservering - bescherming - beschermde gebieden - wetgeving - nederland - richtlijnen (directives) - selectiecriteria - natuurgebieden - nederlandse waddeneilanden - voordelta - noord-holland - vechtstreek - noord-brabant - birds - conservation - protection - reserved areas - legislation - netherlands - directives - selection criteria - natural areas - dutch wadden islands
In dit rapport wordt de aanwijzingssystematiek besproken van negen belangrijke vogelgebieden die in 2000 zijn aangewezen als speciale beschermingszone (sbz) onder de Vogelrichtlijn. Het gaat om gevallen waarbij tegen de aanwijzing als zodanig, tegen de begrenzing van de sbz of tegen beide bezwaar is gemaakt, en waarbij het gebruik van vogelkundige criteria bij de aanwijzing een punt van discussie vormt in de bezwaarschriften. Het gaat hierbij om de volgende gebieden: Voordelta, Waddeneilanden/-Noordzeekustzone/Breebaart, Lauwersmeer, Wormer- en Jisperveld, Ilper-veld/Varkensland/Twiske, Oostelijke Vechtplassen, Zuidlaardermeergebied, Brabantse Wal, en Strabrechtse Heide.
Studies on breeding shorebirds at Medusa Bay, Taimyr, in summer 2001
Tulp, I. ; Schekkerman, H. - \ 2001
Wageningen : Alterra (Alterra-rapport 451) - 111
vogels - nestelen - diergedrag - voortplanting - monitoring - kustgebieden - arctische gebieden - ecologie - geleedpotigen - predatie - rusland - waadvogels - oevers - broedgedrag - fauna - noordpoolgebied - ornithologie - steltlopers - Siberië - birds - nesting - animal behaviour - reproduction - coastal areas - arctic regions - ecology - arthropods - predation - russia - waders - shores
In the Summer of 2001 a combined Dutch-Russian expedition took place to the Willem Barentz field station at Medusa Bay near Dikson in north-western Taimyr. The expedition was organized by Alterra, the Working Group for International Waterbird and Wetland Research (WIWO) and the Agricultural Department of the Dutch Embassy in Moscow. The results obtained by the Alterra team are presented in this report. Subjects of study generally concerned breeding biology of arctic breeding shorebirds, especially aspects related to timing of breeding and adult body condition. This report's purpose is not to discuss the findings thoroughly but merely to summarize the research questions addressed and present all basic information collected during the 2001 season. Topics included are spring arrival and autumn departure of waders from the tundra, breeding phenology, nest success, biometrics of adult waders, chick growth rate, return rates of adult shorebirds, and seasonal and weather-related variation in arthropod availability. Where useful, results are compared with data collected in a previous expedition in 2000. More elaborate analyses and discussion of the data will be made elsewhere.
The coming and going of waders in Taimyr: snapshots from the 2001 season
Schekkerman, H. ; Tulp, I. ; Paters, L. ; Langevoord, O. ; Kirikova, T. - \ 2001
Bulletin / Wader Study Group 96 (2001). - ISSN 0260-3799 - p. 29 - 29.
fauna - ecologie - ornithologie - steltlopers - vogels - Rusland
Population trend and breeding success of black-tailed godwits in the Netherlands: can we sustain a population in agricultural grasslands?
Schekkerman, H. - \ 2001
Bulletin / Wader Study Group 96 (2001). - ISSN 0260-3799 - p. 20 - 21.
fauna - ecologie - grutto - landbouw - ornithologie - steltlopers - weidevogels
Effect van mist op vogelvlieggedrag bij het windpark Eemmeerdijk; zijn er aanwijzingen voor verhoogde aanvaringsrisico's?
Poot, M.J.M. ; Tulp, I. ; Schekkerman, H. ; Bergh, L.J.M. van den; Winden, J. van der - \ 2001
Culemborg : Bureau Waardenburg (Rapport 01-072)
ecologie - natuurbescherming - ornithologie - vogelbescherming - watervogels - windmolenpark - Flevoland
Prefledging energy requirements in shorebirds: energetic implications of self-feeding precocial development
Schekkerman, H. ; Visser, G.H. - \ 2001
The Auk : a quarterly journal of ornithology 118 (2001)4. - ISSN 0004-8038 - p. 944 - 957.
fauna - ecologie - ornithologie
Nadere toetsing van aanwijzing en begrenzing van twee Vogelrichtlijngebieden; aanvulling op Alterra-rapport 328: Nadere toetsing van aanwijzing en begrenzing van negen Vogelrichtlijngebieden
Beintema, A.J. ; Schekkerman, H. - \ 2001
Wageningen : Alterra (Alterra-rapport 374) - 27
vogels - conservering - bescherming - beschermde gebieden - wetgeving - richtlijnen (directives) - selectiecriteria - nederland - ecologie - kust - natuurbescherming - ornithologie - vogelbescherming - Zuid-Holland - Brabant - birds - conservation - protection - reserved areas - legislation - directives - selection criteria - netherlands
In dit rapport wordt de aanwijzingssystematiek besproken van twee belangrijke vogelgebieden die in 2000 zijn aangewezen als speciale beschermingszone onder de Vogelrichtlijn. Het gaat om gevallen waarbij tegen de aanwijzing als zodanig, tegen de begrenzing van de speciale beschermingszone, of tegen beide bezwaar is gemaakt, en waarbij het gebruik van vogelkundige criteria bij de aanwijzing een punt van discussie vormt in de bezwaarschriften. Het gaat hierbij om de volgende gebieden: Voornes Duin en de Weerter- en Budelerbergen. Dit rapport is een aanvulling op het eerder verschenen Alterra-rapport 328, Nadere toetsing van aanwijzing en begrenzing van negen Vogelrichtlijngebieden.
'Vluchtstroken' als instrument in agrarisch weidevogelbeheer; het gebruik van vluchtstroken door gezenderde gruttogezinnen
Schekkerman, H. ; Müskens, G.J.D.M. - \ 2001
Wageningen : Alterra (Alterra-rapport 220) - 51
limosa limosa - voortplanting - nesten - maaien - graslanden - bedrijfsvoering - conservering - monitoring - nederland - weidevogels - reproduction - nests - mowing - grasslands - management - conservation - netherlands - grassland birds
Vluchtstroken voor weidevogels zijn een nieuw instrument in subsidieregelingen voor (agrarisch) weidevogelbeheer, waarbij op vroeg gemaaide graslandpercelen een strook of vlak vegetatie niet wordt meegemaaid, maar pas ten minste twee weken later wordtgemaaid of beweid. De effectiviteit van vluchtstroken is in 1999 en 2000 onderzocht in vier graslandgebieden, waar het terreingebruik werd beschreven van 29 gruttofamilies waarvan een der ouders van een zender was voorzien. Vluchtstroken van 1 en 2 m breed bleken onaantrekkelijk voor grutto's. Percelen met bredere vluchtstroken werden, in verhouding tot hun oppervlak, veel vaker gebruikt door gruttogezinnen dan recentelijk gemaaide percelen zonder vluchtstrook, en vrijwel even vaak als ongemaaide en hergroeiende percelen met een grashoogte van meer dan 15-20 cm. Vluchtstroken, mits voldoende breed, vormen dus een zinvolle aanvulling op het later maaien van gehele percelen.
Produceren grutto's Limosa limosa in agrarisch grasland voldoende jongen voor een duurzame populatie?
Schekkerman, H. ; Müskens, G.J.D.M. - \ 2000
Limosa 73 (2000)4. - ISSN 0024-3620 - p. 121 - 134.
limosa limosa - graslanden - graslandbeheer - weiden - vegetatiebeheer - bedrijfsvoering - maaien - natuurbescherming - voortplanting - voortplantingsvermogen - nestelen - nesten - agrarische bedrijfsvoering - populatie-ecologie - voortplantingsgedrag - broedplaatsen - overleving - vogelnesten - weidevogels - populatiebiologie - agrarisch natuurbeheer - ecologie - fauna - grasland - grutto - ornithologie - steltloper - weidevogel - grasslands - grassland management - pastures - vegetation management - management - mowing - nature conservation - reproduction - reproductive performance - nesting - nests - farm management - population ecology - reproductive behaviour - breeding places - survival - birds' nests - grassland birds - population biology - agri-environment schemes
Door het volgen van met zenders uitgeruste grutto's werden gegevens verzameld over uitkomstsucces, vervolglegsels en kuikenoverleving in agrarische graslandgebieden met vormen van agrarisch natuurbeheer in West- en Midden-Nederland. In de meeste gevallen was het reproductiesucces te laag om verdere achteruitgang van de soort te voorkomen. Agrarisch natuurbeheer biedt wel perspectieven, maar vooral in het maaibeheer zijn aanpassingen nodig
Overzomerende grauwe ganzen in het noordelijk Deltagebied : een modelmatige benadering van de aantalontwikkeling bij verschillende beheersscenario's
Schekkerman, H. ; Klok, T.C. ; Voslamber, B. ; Turnhout, C. van; Willems, F. ; Ebbinge, B.S. - \ 2000
Wageningen : Alterra (SOVON-onderzoeksrapport 2006/06 / Alterra-rapport 139) - 73
anser - ganzen - populatiedynamica - ecologie - dichtheidsafhankelijkheid - nestelen - overleving - voortplanting - bedrijfsvoering - modellen - oogstschade - nederland - zuid-holland - fauna - landbouwschade - ornithologie - trekvogels - Zeeland - Brabant - geese - population dynamics - ecology - density dependence - nesting - survival - reproduction - management - models - crop damage - netherlands
De broedpopulatie van de grauwe gans in het noordelijk Deltagebied neemt sterk toe, en dat leidt in toenemende mate tot landbouwschade in het zomerhalfjaar. In dit rapport wordt, op grond van gegevens over overleving en reproductiesucces, afkomstig uit Zweden en uit Oost-Nederland, een populatiemodel gepresenteerd, waarmee de te verwachten toekomstige populatieontwikkelingen zijn verkend. De modeluitkomsten zijn sterk afhankelijk van het veronderstelde reproductiesucces en indiceren dat de populatie op termijn zou kunnen toenemen tot ruwweg 10 000-20 000 vogels. De effecten van verschillende mogelijke beheersmaatregelen zijn met scenario's doorgerekend.
Falls of migrant birds around the North Sea: an analysis of current knowledge
Lensink, R. ; Camphuysen, C.J. ; Leopold, M.F. ; Jonkers, D.A. ; Schekkerman, H. ; Dirksen, S. - \ 2000
In: IBSC 25 International Bird Strike Committee; proceedings of the 25th conference of the International Bird Strike Committee, Amterdam, the Netherlands, 17-21 April 2000. Den Haag, IBSC, 2000. Proc. 2 / van Nugteren, J., - p. 215 - 218.
Het gebruik van 'vluchtstroken' door gruttogezinnen
Schekkerman, H. ; Müskens, G.J.D.M. - \ 2000
Wageningen : Alterra (Alterra-rapport 27) - 35
limosa limosa - wildbeheer - natuurbescherming - bescherming - maaien - agrarische bedrijfsvoering - voortplanting - nederland - weidevogels - wildlife management - nature conservation - protection - mowing - farm management - reproduction - netherlands - grassland birds
Vluchtstroken voor weidevogels zijn een nieuw instrument in regelingen voor (agrarisch) weidevogelbeheer, waarbij op vroeg gemaaide graslandpercelen een strook of vlak vegetatie niet wordt meegemaaid, maar pas ten minste twee weken later wordt gemaaidof beweid. De effectiviteit van vluchtstroken is onderzocht in twee graslandgebieden, waar het terreingebruik werd beschreven van vijftien gruttofamilies waarvan één der ouders van een zender was voorzien. Vluchtstroken, mits groot genoeg, bleken door gruttogezinnen te worden gebruikt als schuilplaats en als foerageerhabitat. Vluchtstroken van 1 m breed bleken onaantrekkelijk voor grutto's. Vluchtstrookpercelen werden, in verhouding tot hun oppervlakte, gemiddeld vaker gebruikt door gruttogezinnen dan beweide en recentelijk gemaaide percelen, maar minder vaak dan ongemaaide en hergroeiende percelen met een grashoogte van meer dan 15-20 cm. Vluchtstroken vormen derhalve een aanvulling op het later maaien van gehele percelen.
Studies on breeding shorebirds at Medusa Bay, Taimyr, in Summer 2000
Tulp, I. ; Schekkerman, H. ; Klaassen, R. - \ 2000
Wageningen : Alterra (Alterra-rapport 219) - 85
vogels - nestelen - diergedrag - voortplanting - monitoring - kustgebieden - arctische gebieden - ecologie - geleedpotigen - predatie - rusland - oevers - waadvogels - birds - nesting - animal behaviour - reproduction - coastal areas - arctic regions - ecology - arthropods - predation - russia - waders - shores
In the Summer of 2000 a combined Dutch-Russian expedition took place to the Willem Barentz field station at Medusa Bay near Dikson in north-western Taimyr. The expedition was organized by Alterra, the Working Group for International Waterbird and Wetland Research (WIWO) and the Dutch Agricultural Department of the Dutch Embassy in Moscow. As a background document containing all basic information collected during the 2000 season, the results obtained by the Alterra team and part of the results obtained by the WIWO team will be presented in this report. Its purpose is not to discuss data thoroughly but merely to summarize the research questions addressed and present the basic data. More elaborate analyses and discussion of the data will be made in theform of papers in international refereed journals, in combination with results from the 2001 season. Subjects of study generally concerned breeding biology of arctic breeding shorebirds and were all related to the timing of breeding.
The effects of offshore windfarms on birds
Winden, J. van der; Schekkerman, H. ; Tulp, I. ; Dirksen, S. - \ 2000
In: Technische Eingriffe in marine Lebensräume; Workshop des Budesamtes für Naturschutz, Internationale Naturschutzakademie Insel Vilm, 27.-29. Oktober 1999. Bonn (Germany), BfN, 2000. BfN-Skripten 29 / Merck, T., von Nordheim, H., - p. 126 - 135.
Het nationale weidevogelmeetnet
Teunissen, W.A. ; Schekkerman, H. - \ 1999
Unknown Publisher - 48 p.
Falls of migrant birds, an analysis of current knowledge
Lensink, R. ; Camphuysen, C.J. ; Jonkers, D.A. ; Leopold, M.F. ; Schekkerman, H. ; Dirksen, S. - \ 1999
Culemborg : Bureau Waardenburg (Report 99.55) - 117 p.
Nachtelijke vliegbewegingen van toppereenden bij de Afsluitdijk
Tulp, I. ; Bergh, L.M.J. van den; Dirksen, S. ; Schekkerman, H. - \ 1999
Unknown Publisher - 27 p.
Nachtelijke vliegbewegingen van zee-eenden bij het windpark Tuno Knob in de Oostzee
Tulp, I. ; Schekkerman, H. ; Larsen, J.K. ; Winden, J. van der; Haterd, R.J.W. van de; Horssen, P. van; Dirksen, S. ; Spaans, A.L. - \ 1999
Unknown Publisher - 85 p.
Broedende en overzomerende grauwe ganzen in het noordelijk deltagebied in 1999
Schekkerman, H. ; Jonkers, D.A. ; Ebbinge, B.S. ; Müskens, G.J.D.M. - \ 1999
Wageningen : IBN-DLO - 10 p.
Gruttofamilies in beheersmozaoeken
Schekkerman, H. - \ 1999
De Groene Hollander (1999).
Validation of the doubly labeled water method in growing precocial birds: the importance of assumptions concerning evaporative water loss
Visser, G.H. ; Schekkerman, H. - \ 1999
Physiological and Biochemical Zoology 72 (1999)6. - ISSN 1522-2152 - p. 740 - 749.
Terreingebruik, mobiliteit en metingen van broedsucces van grutto's in de jongenperiode
Schekkerman, H. ; Teunissen, W.A. ; Müskens, G.J.D.M. - \ 1998
Unknown Publisher
Growth, behaviour of broods and weather-related variation in breeding productivity of curlew sandpipers Calidris ferruginea
Schekkerman, H. ; Roomen, M.J.W. van; Underhill, L.G. - \ 1998
Ardea 86 (1998)2. - ISSN 0373-2266 - p. 153 - 168.
Growth and survival of chicks and movements of broods were studied in Curlew Sandpipers in N.E. Taimyr, Siberia, in 1991. Breeding was synchronised, 73% of 30 clutches hatching during 10-15 July. Nests were distributed clumped in dry frost-heaved tundra. Broods were tended by females only and moved from the nest sites to low-lying wet areas up to 2.4 km away during the first week of life. Here, they often formed aggregations of 2-6 broods with females cooperating in predator defence. In 1991 (a lemming peak year), both clutch and chick survival were high, and breeding productivity was c. 2 fledglings per female. Chicks fledged in 14-16 days, and body mass growth was best described by a logistic curve. The growth rate constant K-L was 0.314, which ishigh compared to similar-sized waders studied elsewhere. Growth rate was reduced during cold weather, as was the availability of surface-active arthropods which form the main food source for chicks. Effects of weather on chick survival and breeding productivity were examined by correlating data on annual variation in the proportion of juveniles among wintering birds in South Africa with 18 years of summer weather records from the core of the Taimyr breeding area. After allowing for an effect of three-yearly cyclic variation in lemming abundance on predation of eggs and young by arctic foxes and skuas, breeding productivity was positively correlated with mean temperature in Taimyr during 11-20 July, the period when most young chicks are present in the tundra. Weather thus seems to have effects on chick survival both widespread and large enough to be detected in the wintering areas, and the combination of (inferred) predation pressure and weather conditions during the hedging period explains a large part of the variation in breeding productivity found in this species. We found no correlations between productivity and weather during the pre-laying period, in contrast to several studies on arctic-breeding geese. VA:IBN
Growth of little stint Calidris minuta chicks on the Taimyr peninsula, Siberia
Schekkerman, H. ; Nehls, G. ; Hötker, H. ; Tomkovich, P.S. ; Kania, W. ; Chylarecki, P. ; Soloviev, M. ; Roomen, M. van - \ 1998
Bird Study 1 (1998). - ISSN 0006-3657 - p. 77 - 84.
Slaaptrek van zwarte sterns en visdieven in de omgeving van de windturbine op de sluizen van Den Oever
Dirksen, S. ; Schekkerman, H. ; Winden, J. van der; Poot, M.J.M. ; Lensink, R. ; Bergh, L.M.J. van den; Spaans, A.L. - \ 1998
Culemborg : Bureau Waardenburg (Rapport 98.057) - 39 p.
Mobiliteit van grutto's in de ruime jas
Schekkerman, H. ; Beintema, A.J. ; Bergh, L.M.J. van den - \ 1997
Wageningen : IBN-DLO (IBN - rapport 331) - 33
territorium - habitats - numenius - limosa - tringa - bescherming - bedreigde soorten - nederland - limosa limosa - weidevogels - territory - protection - endangered species - netherlands - grassland birds
Graslandbeheer en groeimogelijkheden voor weidevogelkuikens
Schekkerman, H. - \ 1997
Wageningen : DLO-Instituut voor Bos- en Natuuronderzoek (IBN-rapport 292) - 92 p.
Invloed van graslandbeheer op de groeimogelijkheden van gruttokuikens
Schekkerman, H. - \ 1996
Limosa 69 (1996)1. - ISSN 0024-3620 - p. 25 - 26.
Populatieschattingen en 1%-normen voor in Nederland voorkomende watervogelsoorten: voorstellen voor standaardisatie
Meininger, P.L. ; Schekkerman, H. ; Roomen, M.W.J. van - \ 1995
Limosa 68 (1995)1. - ISSN 0024-3620 - p. 41 - 48.
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