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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Restoration of inland brackish vegetation by large-scale transfer of coastal driftline material
Wolters, Mineke ; Vries, Saskia de; Ozinga, Wim A. ; Bakker, Jan P. - \ 2017
Applied Vegetation Science 20 (2017)4. - ISSN 1402-2001 - p. 641 - 650.
brackish habitat - dispersal - driftline - grazing - saline habitat - salinity - sheep - target species - top soil removal - transfer rate

Question: Does large-scale transfer of coastal driftline material enhance the establishment of inland brackish vegetation?. Location: The Klutenplas of 11 ha, a formerly reclaimed agricultural field, north coast of the Netherlands. Methods: A large quantity of coastal driftline material of local origin was transferred to the restoration site in 2006 after top soil removal in 2005 leaving bare areas for control plots. A priori species composition of the driftline was analysed in a greenhouse germination study. Target species were assigned to saline and brackish ecological species groups and present and historic regional occurrences. Our procedure for selecting target species resulted in a list of 98 species characteristic of terrestrial salt and brackish ecological species groups. The establishment of plant species in the field was recorded annually from 2006 to 2009, with a final survey in 2012. A comparison between locations with and without driftline was made. The entire study site was grazed with sheep. Results: Driftline material contained 39 species, including 26 target species. During the first 4 yr, the mean number of target species in the established vegetation of driftline plots was significantly higher than in control plots. When corrected for spontaneous occurrence by natural colonization in control plots, 44% of the target species in the established vegetation of driftline plots during the first 4 yr could be attributed to the transferred material. After 7 yr driftline and control plots converged to similar levels, probably as a result of dispersal by wind and animals. Conclusions: Transfer of coastal driftline material enhanced the rate of establishment of inland brackish vegetation for at least the first 4 yr.

Data from: Gene flow and effective population sizes of the butterfly Maculinea alcon in a highly fragmented, anthropogenic landscape
Vanden Broeck, A.H. ; Maes, Dirk ; Kelager, Andreas ; Wynhoff, Irma ; Wallis de Vries, M.F. ; Nash, David R. ; Oostermeijer, J.G.B. ; Dyck, Hans van; Mergeay, Joachim - \ 2017
gene flow - microsatellite data - effective population size - dispersal - sedentary species - Maculinea alcon - Phengaris alcon
The file Maculinea alcon microsatellite data includes the data from 12 microsatellites for 398 unique genotypes of Maculinea alcon from in total 14 sampling locations located in Belgium and The Netherlands. The data matrix also include the spatial coordinates of each sampled population, given in the two last columns.
Aardappel: knolgewas van wereldformaat : De oorsprong van de aardappel (herziene versie)
Pistorius, R. ; Hoekstra, R. - \ 2017
Wageningen : Centrum voor Genetische Bronnen Nederland - 20 p.
aardappelen - herkomst - verspreiding - genetische bronnen van plantensoorten - rassen (planten) - potatoes - provenance - dispersal - plant genetic resources - varieties
In vier eeuwen tijd is de aardappel uitgegroeid van een lokaal voedselgewas tot het op drie na grootste bulkvoedselgewas ter wereld. Nederland is in de laatste eeuw uitgegroeid tot 's werelds grootste exporteur van pootaardappelen. De aardappelteelt en -export liggen diep verankerd in onze landbouwgeschiedenis.
Improving communication and validation of ecological models : a case study on the dispersal of aquatic macroinvertebrates
Augusiak, Jacqueline A. - \ 2016
University. Promotor(en): Paul van den Brink, co-promotor(en): V. Grimm. - Wageningen : Wageningen University - ISBN 9789462579378 - 192
macroinvertebrates - aquatic invertebrates - ecological modeling - ecology - models - dispersal - environmental policy - macroinvertebraten - waterinvertebraten - ecologische modellering - ecologie - modellen - verspreiding - milieubeleid

In recent years, ecological effect models have been put forward as tools for supporting environmental decision-making. Often they are the only way to take the relevant spatial and temporal scales and the multitude of processes characteristic to ecological systems into account. Particularly for environmental risk assessments of pesticides the potential benefits of including modelling studies were recognized and a dialogue between different stakeholder groups was opened. Representatives from academia, pesticide-producing industries, and regulators are nowadays discussing their needs, possibilities, and ways of implementation for improving the use and usefulness of such models. However, it quickly became evident that not all involved parties possess the same background knowledge in regards to modelling terminology and model quality understanding. Proper communication of a given model's structure, robustness, and soundness is crucial to render a model of real use to the decision-making. Doubts about a model's quality and mode of operation may lead to an immediate rejection of the conclusions drawn from its estimations.

In this thesis, we addressed this point of concern, and performed a literature review focusing on aspects surrounding quality assessments, validation, and communication of models. "Validation" was identified as a catch-all term, which is thus useless for any practical purpose. Based on the review, we developed a framework that splits the seemingly blurry process into associated components and introduce the term ‘evaludation’, a fusion of ‘evaluation’ and ‘validation’, to describe the entire process of assessing a model's quality and reliability. Considering the iterative nature of model development, the modelling cycle, we identified six essential elements of evaludation: (i) ‘data evaluation’ for scrutinising the quality of numerical and qualitative data used for model development and testing; (ii) ‘conceptual model evaluation’ for examining the simplifying assumptions underlying a model's design; (iii) ‘implementation verification’ for testing the model's implementation in equations and as a computer programme; (iv) ‘model output verification’ for comparing model output to data and patterns that guided model design and were possibly used for calibration; (v) ‘model analysis’ for exploring the model's sensitivity to changes in parameters and process formulations to make sure that the mechanistic basis of main behaviours of the model has been well understood; and (vi) ‘model output corroboration’ for comparing model output to new data and patterns that were not used for model development and parameterisation.

In a subsequent step, we used the evaludation framework to re-evaluate and adjust the documentation framework TRACE (TRAnsparent and Comprehensive Eco- logical modelling; Schmolke et al. 2010), a general framework for documenting a model's rationale, design, and testing. TRACE documents should provide convincing evidence that a model was thoughtfully designed, correctly implemented, thoroughly tested, well understood, and appropriately used for its intended purpose. TRACE documents link the science underlying a model to its application, thereby also linking modellers and model users, for example stakeholders, decision makers, and developers of policies. TRACE thus becomes a tool for planning, documenting, and assessing model evaludation, which includes understanding the rationale behind a model and its envisaged use.

To provide an example of the measures that can be taken to increase general trust in a model's design and output, we chose MASTEP (Metapopulation model for Assessing Spatial and Temporal Effects of Pesticides) for a case study. MASTEP is an individual-based model used to describe the effects on and recovery of the water louse Asellus aquaticus after exposure to an insecticide in pond, ditch, and stream scenarios. The model includes processes of mortality of A. aquaticus, life history, random walk between cells and density dependence of population regulation. One of the submodels receiving particular criticism was the random walk procedure and the uncertainty attached to the parameters used. The parameters were estimated based on experimental studies performed under very limiting conditions.

We designed and performed experiments to derive more precise parameters and to better understand the movement behaviour of this freshwater isopod. The experimental procedure that we developed employed video tracking of marked individuals that were introduced alone or as part of a group of unmarked individuals into arenas of approximately 1m2 in size. We recorded the paths of the marked individuals under a set of different conditions, i.e. presence or absence of food or shelter, population density, and after sublethal exposure to chlorpyrifos and imidacloprid. Based on the experimental findings, we refined the movement modelling procedure used in MASTEP to derive more realistic dispersal estimates, with which we revisited a modelling study performed previously by Galic et al. (2012). In this study, the effects of pesticide application timing on population dynamics and recovery times were tested and compared to outcomes from previous versions. It was furthermore possible to integrate an increased level of environmental complexity that could not be addressed before due to a lack of data. Compared to former versions of the population model, recovery times did not change significantly when the same movement parameters were applied to all simulated individuals. This indicates that the previous assumptions already yielded robust estimations. Accounting for life stage dependent movement restraints, though, delayed recovery when exposure occurred shortly before a reproduction cycle. Based on these findings, it was concluded that an increase of ever more realism and environmental complexity in modelling studies needs to be done carefully on a case-by-case basis. Increased realism in models can introduce an unwarranted increase in model complexity and uncertainty, which is not always supporting an improved credibility level of a model.

Despite the need for basic ecological research for more comprehensive ecological models, we further argue that a modelling study in general can benefit greatly from an improved plan that considers communication needs from the start. Considering such needs early on can help develop a time- and cost-saving strategy for model testing and data collection, while providing a thorough understanding of a model's underlying mechanisms across several layers of stakeholder groups.

Grassnuitkevers toekomstige bedreiging voor Nederland?
Vliet, Arnold van - \ 2016
plant pests - insect pests - dispersal - sphenophorus - sphenophorus venatus - golf courses

Met de uitbreiding van grassnuitkevers in diverse landen zoals de Verenigde Staten en Spanje neemt de zorg toe dat er zich ook grassnuitkeversoorten in Nederland gaan vestigen door het verslepen van plantmateriaal of via vakantiegangers. Grassnuitkevers zijn vooral schadelijk voor gras, maar doen zich ook te goed aan mais, tarwe en varens

Emergent strategies for detection and control of biofilms in food processing environments
Besten, H.M.W. den; Ding, Y. ; Abee, T. ; Liang, Yang - \ 2016
In: Advances in Food Biotechnology / Rai V, Ravishankar, Chichester, UK : John Wiley and Sons - ISBN 9781118864555
biofilm - resistance - detection - control - dispersal
Biofilms are dense surface-attached microbial communities consisting of bacterial colonies embedded in their self-generated matrix materials. Different bacteria species that exist within a biofilm are positioned within many different microenvironments defined by nutrient availability, pH and oxygen levels. To adapt to these myriad niches, bacteria therefore show numerous phenotypes and enormous metabolic and replicative heterogeneity. This heterogeneity provides the biofilm community with great capacity to withstand challenges. Biofilms formed in the food-processing environments cause recalcitrant contaminations and food spoilage, which pose a huge threat to public health. The distinct physiology and slow growth rate of biofilm cells hinder the detection of biofilms hidden in the food-processing environments. Conventional cleaning and disinfecting strategies could be ineffective to eradicate biofilms. The present chapter will focus on describing the latest strategies for detection and control of biofilms in food-processing environments.
Invasieve soorten Waddenzee: : Introductiekansen van probleemsoorten via schelpdiertransport
Tamis, J.E. ; Sneekes, A.C. ; Jak, R.G. - \ 2015
Den Helder : IMARES (Rapport / IMARES C173/15) - 49 p.
invasieve soorten - schaaldieren - veevervoer - verspreiding - aquatische ecosystemen - milieueffect - waddenzee - nederland - invasive species - shellfish - transport of animals - dispersal - aquatic ecosystems - environmental impact - wadden sea - netherlands
Early-season movement dynamics of phytophagous pest and natural enemies across a native vegetation-crop ecotone
Macfadyen, S. ; Hopkinson, J. ; Parry, H. ; Neave, M.J. ; Bianchi, F.J.J.A. ; Zalucki, M.P. ; Schellhorn, N.A. - \ 2015
Agriculture, Ecosystems and Environment 200 (2015). - ISSN 0167-8809 - p. 110 - 118.
managing ecosystem services - agricultural landscape - biological-control - spatial scales - dispersal - colonization - predators - ecology - parasitoids - suppression
There is limited understanding about how insect movement patterns are influenced by landscape features, and how landscapes can be managed to suppress pest phytophage populations in crops. Theory suggests that the relative timing of pest and natural enemy arrival in crops may influence pest suppression. However, there is a lack of data to substantiate this claim. We investigate the movement patterns of insects from native vegetation (NV) and discuss the implications of these patterns for pest control services. Using bi-directional interception traps we quantified the number of insects crossing an NV/crop ecotone relative to a control crop/crop interface in two agricultural regions early in the growing season. We used these data to infer patterns of movement and net flux. At the community-level, insect movement patterns were influenced by ecotone in two out of three years by region combinations. At the functional-group level, pests and parasitoids showed similar movement patterns from NV very soon after crop emergence. However, movement across the control interface increased towards the end of the early-season sampling period. Predators consistently moved more often from NV into crops than vice versa, even after crop emergence. Not all species showed a significant response to ecotone, however when a response was detected, these species showed similar patterns between the two regions. Our results highlight the importance of NV for the recruitment of natural enemies for early season crop immigration that may be potentially important for pest suppression. However, NV was also associated with crop immigration by some pest species. Hence, NV offers both opportunities and risks for pest management. The development of targeted NV management may reduce the risk of crop immigration by pests, but not of natural enemies.
Indirect interactions among tropical tree species through shared rodent seed predators: a novel mechanism of tree species coexistence
Garzon-Lopez, C.X. ; Ballesteros-Mejia, L. ; Ordonez, A. ; Bohlman, S.A. ; Olff, H. ; Jansen, P.A. - \ 2015
Ecology Letters 18 (2015)8. - ISSN 1461-023X - p. 752 - 760.
rain-forest tree - apparent competition - density-dependence - spatial autocorrelation - plant recruitment - dispersal - palm - herbivores - diversity - survival
The coexistence of numerous tree species in tropical forests is commonly explained by negative dependence of recruitment on the conspecific seed and tree density due to specialist natural enemies that attack seeds and seedlings (‘Janzen–Connell’ effects). Less known is whether guilds of shared seed predators can induce a negative dependence of recruitment on the density of different species of the same plant functional group. We studied 54 plots in tropical forest on Barro Colorado Island, Panama, with contrasting mature tree densities of three coexisting large seeded tree species with shared seed predators. Levels of seed predation were far better explained by incorporating seed densities of all three focal species than by conspecific seed density alone. Both positive and negative density dependencies were observed for different species combinations. Thus, indirect interactions via shared seed predators can either promote or reduce the coexistence of different plant functional groups in tropical forest.
Studying the movement behaviour of benthic macroinvertebrates with automated video tracking
Augusiak, J.A. ; Brink, P.J. van den - \ 2015
Ecology and Evolution 5 (2015)8. - ISSN 2045-7758 - p. 1563 - 1575.
laboratory experiments - stream invertebrates - ecosystem function - dispersal - sensitivity - directions - landscapes - dimension - paradigm - ecology
Quantifying and understanding movement is critical for a wide range of questions in basic and applied ecology. Movement ecology is also fostered by technological advances that allow automated tracking for a wide range of animal species. However, for aquatic macroinvertebrates, such detailed methods do not yet exist. We developed a video tracking method for two different species of benthic macroinvertebrates, the crawling isopod Asellus aquaticus and the swimming fresh water amphipod Gammarus pulex. We tested the effects of different light sources and marking techniques on their movement behavior to establish the possibilities and limitations of the experimental protocol and to ensure that the basic handling of test specimens would not bias conclusions drawn from movement path analyses. To demonstrate the versatility of our method, we studied the influence of varying population densities on different movement parameters related to resting behavior, directionality, and step lengths. We found that our method allows studying species with different modes of dispersal and under different conditions. For example, we found that gammarids spend more time moving at higher population densities, while asellids rest more under similar conditions. At the same time, in response to higher densities, gammarids mostly decreased average step lengths, whereas asellids did not. Gammarids, however, were also more sensitive to general handling and marking than asellids. Our protocol for marking and video tracking can be easily adopted for other species of aquatic macroinvertebrates or testing conditions, for example, presence or absence of food sources, shelter, or predator cues. Nevertheless, limitations with regard to the marking protocol, material, and a species’ physical build need to be considered and tested before a wider application, particularly for swimming species. Data obtained with this approach can deepen the understanding of population dynamics on larger spatial scales and of the effects of different management strategies on a species’ dispersal potential.
Functional Trait Strategies of Trees in Dry and Wet Tropical Forests Are Similar but Differ in Their Consequences for Succession
Lohbeck, M.W.M. ; Lebrija-Trejos, E.E. ; Martinez-Ramos, M. ; Meave, J.A. ; Poorter, L. ; Bongers, F. - \ 2015
PLoS One 10 (2015)4. - ISSN 1932-6203
plant economics spectrum - leaf life-spans - seed size - secondary succession - neotropical forests - shade-tolerance - woody-plants - trade-off - drought - dispersal
Global plant trait studies have revealed fundamental trade-offs in plant resource economics. We evaluated such trait trade-offs during secondary succession in two species-rich tropical ecosystems that contrast in precipitation: dry deciduous and wet evergreen forests of Mexico. Species turnover with succession in dry forest largely relates to increasing water availability and in wet forest to decreasing light availability. We hypothesized that while functional trait trade-offs are similar in the two forest systems, the successful plant strategies in these communities will be different, as contrasting filters affect species turnover. Research was carried out in 15 dry secondary forest sites (5-63 years after abandonment) and in 17 wet secondary forest sites (
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.
Pilot study on behaviour of sharks around Saba using acoustic telemetry - Progress report 2014
Winter, H.V. ; Vink, D. ; Beek, I.J.M. van - \ 2015
IJmuiden : IMARES (Report / IMARES Wageningen UR C026/15) - 21
haaien - saba - zeereservaten - telemetrie - migratie - verspreiding - universitair onderzoek - sharks - marine protected areas - telemetry - migration - dispersal - university research
Worldwide many shark populations are in strong decline mainly due to fisheries. Population status of sharks in the Caribbean is still poorly known. In order to be able to take effective measures to protect sharks, insight in their spatial behaviour during different life stages is required. Do marine parks enhance shark populations and if so at what scale? This pilot study mainly aims at determining the feasibility of using telemetry around Saba and at a later stage at the Saba Bank and surrounding islands, e.g. what logistics and which co-operation, catching and deployment methods are required to set-up telemetric experiments for target shark species, and to get a first insight of the scale of movement patterns of the target shark species.
Quantification of motility of carabid beetles in farmland
Allema, A.B. ; Werf, W. van der; Groot, J.C.J. ; Hemerik, L. ; Gort, G. ; Rossing, W.A.H. ; Lenteren, J.C. van - \ 2015
Bulletin of Entomological Research 105 (2015)2. - ISSN 0007-4853 - p. 234 - 244.
inhabiting cereal fields - pterostichus-melanarius - agricultural landscapes - movement patterns - surface-activity - activity-density - ground beetles - coleoptera - dispersal - models
Quantification of the movement of insects at field and landscape levels helps us to understand their ecology and ecological functions. We conducted a meta-analysis on movement of carabid beetles (Coleoptera: Carabidae), to identify key factors affecting movement and population redistribution. We characterize the rate of redistribution using motility µ (L2 T-1), which is a measure for diffusion of a population in space and time that is consistent with ecological diffusion theory and which can be used for upscaling short-term data to longer time frames. Formulas are provided to calculate motility from literature data on movement distances. A field experiment was conducted to measure the redistribution of mass-released carabid, Pterostichus melanarius in a crop field, and derive motility by fitting a Fokker–Planck diffusion model using inverse modelling. Bias in estimates of motility from literature data is elucidated using the data from the field experiment as a case study. The meta-analysis showed that motility is 5.6 times as high in farmland as in woody habitat. Species associated with forested habitats had greater motility than species associated with open field habitats, both in arable land and woody habitat. The meta-analysis did not identify consistent differences in motility at the species level, or between clusters of larger and smaller beetles. The results presented here provide a basis for calculating time-varying distribution patterns of carabids in farmland and woody habitat. The formulas for calculating motility can be used for other taxa.
Survival, reproduction, and immigration explain the dynamics of a local Red-backed Shrike population in the Netherlands
Hemerik, L. ; Geertsma, M. ; Waasdorp, S. ; Middelveld, R.P. ; Kleef, H. van; Klok, T.C. - \ 2015
Journal of Ornithology 156 (2015)1. - ISSN 2193-7192 - p. 35 - 46.
lanius-collurio - marked animals - birds - consequences - dispersal - patterns - weather
Populations of many bird species strongly declined in Western Europe in the late twentieth century. One such species is the Red-backed Shrike in the Netherlands. In one of the last strongholds of this species, the Bargerveen Reserve, the breeding population flourished in the 1990s due to rewetting management. However, further development of the area has led to a decline in breeding numbers such that the population is now less than half the size it was in the 1990s. Here, we analyze the vital rates of the Red-backed Shrike population in the Bargerveen. In 2001–2008, nestlings in this population were individually marked, and resighting data was collected during the breeding seasons of 2002–2009. We used estimates of vital rates based on monitoring in 2001 until 2009 to diagnose the population dynamics. Mark–recapture data were analyzed with the program MARK. The most parsimonious model gave age- and gender-specific survival probabilities of 0.12 for first-year females, 0.64 for older females, 0.20 for first-year males, and 0.54 for older males (with overlapping confidence intervals for the gender-specific adult survival values). The estimated yearly resighting probabilities were gender specific, with a higher probability observed for males (0.81) than for females (0.53). For 2001–2009, we computed an average number of offspring per breeding pair of 2.91 (with 72 % of the pairs breeding successfully). Using these vital rates, we parameterized a simple matrix model. The resulting yearly growth was 0.80. Adult survival had an elasticity of 0.83, while juvenile survival and reproduction both had an elasticity of 0.20. Because the population numbers have stabilized since 2005, the observed yearly population growth suggests that 20 % of the Red-backed Shrikes breeding in the Bargerveen are immigrants. Comparison with data on other Red-backed Shrike populations indicates that juvenile and adult survival rates can be improved in the Bargerveen Reserve. Appropriate management measures to accomplish this are discussed.
The earliest securely-dated hominin artefact in Anatolia?
Maddy, D. ; Schreve, D. ; Demir, T. ; Veldkamp, A. ; Wijbrans, J.R. ; Gorp, W. van; Hinsbergen, D.J.J. van; Dekkers, M.J. ; Scaife, R. ; Schoorl, J.M. ; Stemerdink, C. ; Schriek, T. van der - \ 2015
Quaternary Science Reviews 109 (2015). - ISSN 0277-3791 - p. 68 - 75.
geomagnetic secular variation - river terrace staircase - western turkey - gediz river - volcanic field - dmanisi - georgia - kula - dispersal - caucasus
Anatolia lies at the gateway from Asia into Europe and has frequently been favoured as a route for Early Pleistocene hominin dispersal. Although early hominins are known to have occupied Turkey, with numerous finds of Lower Palaeolithic artefacts documented, the chronology of their dispersal has little reliable stratigraphical or geochronological constraint, sites are rare, and the region's hominin history remains poorly understood as a result. Here, we present a Palaeolithic artefact, a hard-hammer flake, from fluvial sediments associated with the Early Pleistocene Gediz River of Western Turkey. This previously documented buried river terrace sequence provides a clear stratigraphical context for the find and affords opportunities for independent age estimation using the numerous basaltic lava flows that emanated from nearby volcanic necks and aperiodically encroached onto the contemporary valley floors. New 40Ar/39Ar age estimates from these flows are reported here which, together with palaeomagnetic measurements, allow a tightly-constrained chronology for the artefact-bearing sediments to be established. These results suggest that hominin occupation of the valley occurred within a time period spanning ~1.24 Ma to ~1.17 Ma, making this the earliest, securely-dated, record of hominin occupation in Anatolia.
Movement Behaviour of the Carabid Beetle Pterostichus melanarius in Crops and a Habitat Interface Explains Patterns of Population Redistribution in the Field
Allema, B. ; Werf, W. van der; Lenteren, J.C. van; Hemerik, L. ; Rossing, W.A.H. - \ 2014
PLoS One 9 (2014)12. - ISSN 1932-6203 - 20 p.
coleoptera carabidae - generalist predators - diffusion-model - dispersal - edges - dynamics - density - slugs
Animals may respond to habitat quality and habitat edges and these responses may affect their distribution between habitats. We studied the movement behaviour of a ground-dwelling generalist predator, the carabid beetle Pterostichus melanarius (Illiger). We performed a mark-recapture experiment in two adjacent habitats; a large plot with oilseed radish (Raphanus sativus) and a plot with rye (Secale cereale). We used model selection to identify a minimal model representing the mark-recapture data, and determine whether habitat-specific motility and boundary behaviour affected population redistribution. We determined movement characteristics of P. melanarius in laboratory arenas with the same plant species using video recording. Both the field and arena results showed preference behaviour of P. melanarius at the habitat interface. In the field, significantly more beetles moved from rye to oilseed radish than from radish to rye. In the arena, habitat entry was more frequent into oilseed radish than into rye. In the field, movement was best described by a Fokker-Planck diffusion model that contained preference behaviour at the interface and did not account for habitat specific motility. Likewise, motility calculated from movement data using the Patlak model was not different between habitats in the arena studies. Motility (m2 d-1) calculated from behavioural data resulted in estimates that were similar to those determined in the field. Thus individual behaviour explained population redistribution in the field qualitatively as well as quantitatively. The findings provide a basis for evaluating movement within and across habitats in complex agricultural landscapes with multiple habitats and habitat interfaces.
Kleine bijenkastkever aangetroffen in Italië
Cornelissen, B. ; Pelgrim, W. - \ 2014
Bijenhouden 8 (2014)7, november 2014. - ISSN 1877-9786 - p. 25 - 26.
bijenhouderij - bijenziekten - aethina tumida - italië - verspreiding - dierziektepreventie - apidae - honingbijen - diergezondheid - bestrijdingsmethoden - beekeeping - bee diseases - italy - dispersal - animal disease prevention - honey bees - animal health - control methods
Voor de tweede keer in 10 jaar heeft de kleine bijenkastkever (Aethina tumida) voet aan de grond gekregen in Europa. Een eerste uitbraak in Portugal in 2004 werd snel ingedamd, maar een nieuwe uitbraak in het zuiden van Italië lijkt van permanente aard.
Effect of light quality on movement of Pterostichus melanarius (Coleoptera: Carabidae)
Allema, A.B. - \ 2014
insects - movement activity - movement behavior - movement speed - red light sensitivity - resting behavior - arable land - insect pests - natural enemies - predatory insects - predators - pterostichus melanarius - dispersal - movement - animal behavior - quantitative analysis - motility - modeling - methodology
The aim of this project was to study the effect of red light on night time behaviour of Pterostichus melanarius (Coleoptera: Carabidae). An experiment was conducted in experimental arenas in the autumn of 2008. Beetles were recorded 20 min per hour during a period of 8 hours under red light, near infrared radiation and white light.
No evidence of the effect of extreme weather events on annual occurrence of four groups of ectothermic species
Malinowska, A.H. ; Strien, A.J. van; Verboom, J. ; Wallis de Vries, M.F. ; Opdam, P. - \ 2014
PLoS One 9 (2014)10. - ISSN 1932-6203 - 10 p.
climate-change - metapopulation dynamics - habitat fragmentation - population-dynamics - occupancy models - european climate - range expansion - dispersal - trends - impact
Weather extremes may have strong effects on biodiversity, as known from theoretical and modelling studies. Predicted negative effects of increased weather variation are found only for a few species, mostly plants and birds in empirical studies. Therefore, we investigated correlations between weather variability and patterns in occupancy, local colonisations and local extinctions (metapopulation metrics) across four groups of ectotherms: Odonata, Orthoptera, Lepidoptera, and Reptilia. We analysed data of 134 species on a 1×1 km-grid base, collected in the last 20 years from the Netherlands, combining standardised data and opportunistic data. We applied dynamic site-occupancy models and used the results as input for analyses of (i) trends in distribution patterns, (ii) the effect of temperature on colonisation and persistence probability, and (iii) the effect of years with extreme weather on all the three metapopulation metrics. All groups, except butterflies, showed more positive than negative trends in metapopulation metrics. We did not find evidence that the probability of colonisation or persistence increases with temperature nor that extreme weather events are reflected in higher extinction risks. We could not prove that weather extremes have visible and consistent negative effects on ectothermic species in temperate northern hemisphere. These findings do not confirm the general prediction that increased weather variability imperils biodiversity. We conclude that weather extremes might not be ecologically relevant for the majority of species. Populations might be buffered against weather variation (e.g. by habitat heterogeneity), or other factors might be masking the effects (e.g. availability and quality of habitat). Consequently, we postulate that weather extremes have less, or different, impact in real world metapopulations than theory and models suggest.
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