Author Correction: Phosphopantetheinyl transferase (Ppt)-mediated biosynthesis of lysine, but not siderophores or DHN melanin, is required for virulence of Zymoseptoria tritici on wheat
Derbyshire, Mark C. ; Gohari, Amir Mirzadi ; Mehrabi, Rahim ; Kilaru, Sreedhar ; Steinberg, Gero ; Ali, Solaf ; Bailey, Andy ; Hammond-Kosack, Kim ; Kema, Gert H.J. ; Rudd, Jason J. - \ 2019
Scientific Reports 9 (2019)1. - ISSN 2045-2322
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Phosphopantetheinyl transferase (Ppt)-mediated biosynthesis of lysine, but not siderophores or DHN melanin, is required for virulence of Zymoseptoria tritici on wheat
Derbyshire, Mark C. ; Gohari, Amir Mirzadi ; Mehrabi, Rahim ; Kilaru, Sreedhar ; Steinberg, Gero ; Ali, Solaf ; Bailey, Andy ; Hammond-Kosack, Kim ; Kema, Gert H.J. ; Rudd, Jason J. - \ 2018
Scientific Reports 8 (2018)1. - ISSN 2045-2322
Zymoseptoria tritici is the causal agent of Septoria tritici blotch (STB) disease of wheat. Z. tritici is an apoplastic fungal pathogen, which does not penetrate plant cells at any stage of infection, and has a long initial period of symptomless leaf colonisation. During this phase it is unclear to what extent the fungus can access host plant nutrients or communicate with plant cells. Several important primary and secondary metabolite pathways in fungi are regulated by the post-translational activator phosphopantetheinyl transferase (Ppt) which provides an essential co-factor for lysine biosynthesis and the activities of non-ribosomal peptide synthases (NRPS) and polyketide synthases (PKS). To investigate the relative importance of lysine biosynthesis, NRPS-based siderophore production and PKS-based DHN melanin biosynthesis, we generated deletion mutants of ZtPpt. The ∆ZtPpt strains were auxotrophic for lysine and iron, non-melanised and non-pathogenic on wheat. Deletion of the three target genes likely affected by ZtPpt loss of function (Aar- lysine; Nrps1-siderophore and Pks1- melanin), highlighted that lysine auxotrophy was the main contributing factor for loss of virulence, with no reduction caused by loss of siderophore production or melanisation. This reveals Ppt, and the lysine biosynthesis pathway, as potential targets for fungicides effective against Z. tritici.
Toward sustainable environmental quality : Priority research questions for Europe
Brink, Paul J. Van den; Boxall, Alistair B.A. ; Maltby, Lorraine ; Brooks, Bryan W. ; Rudd, Murray A. ; Backhaus, Thomas ; Spurgeon, David ; Verougstraete, Violaine ; Ajao, Charmaine ; Ankley, Gerald T. ; Apitz, Sabine E. ; Arnold, Kathryn ; Brodin, Tomas ; Cañedo-Argüelles, Miguel ; Chapman, Jennifer ; Corrales, Jone ; Coutellec, Marie Agnès ; Fernandes, Teresa F. ; Fick, Jerker ; Ford, Alex T. ; Giménez Papiol, Gemma ; Groh, Ksenia J. ; Hutchinson, Thomas H. ; Kruger, Hank ; Kukkonen, Jussi V.K. ; Loutseti, Stefania ; Marshall, Stuart ; Muir, Derek ; Ortiz-Santaliestra, Manuel E. ; Paul, Kai B. ; Rico, Andreu ; Rodea-Palomares, Ismael ; Römbke, Jörg ; Rydberg, Tomas ; Segner, Helmut ; Smit, Mathijs ; Gestel, Cornelis A.M. van; Vighi, Marco ; Werner, Inge ; Zimmer, Elke I. ; Wensem, Joke van - \ 2018
Environmental Toxicology and Chemistry 37 (2018)9. - ISSN 0730-7268 - p. 2281 - 2295.
Chemical management - Environmental risk assessment - Global megatrends - Key questions exercise - Sustainability
The United Nations' Sustainable Development Goals have been established to end poverty, protect the planet, and ensure prosperity for all. Delivery of the Sustainable Development Goals will require a healthy and productive environment. An understanding of the impacts of chemicals which can negatively impact environmental health is therefore essential to the delivery of the Sustainable Development Goals. However, current research on and regulation of chemicals in the environment tend to take a simplistic view and do not account for the complexity of the real world, which inhibits the way we manage chemicals. There is therefore an urgent need for a step change in the way we study and communicate the impacts and control of chemicals in the natural environment. To do this requires the major research questions to be identified so that resources are focused on questions that really matter. We present the findings of a horizon-scanning exercise to identify research priorities of the European environmental science community around chemicals in the environment. Using the key questions approach, we identified 22 questions of priority. These questions covered overarching questions about which chemicals we should be most concerned about and where, impacts of global megatrends, protection goals, and sustainability of chemicals; the development and parameterization of assessment and management frameworks; and mechanisms to maximize the impact of the research. The research questions identified provide a first-step in the path forward for the research, regulatory, and business communities to better assess and manage chemicals in the natural environment.
Plant pathogen effector proteins as manipulators of host microbiomes?
Snelders, Nick C. ; Kettles, Graeme J. ; Rudd, Jason J. ; Thomma, Bart P.H.J. - \ 2018
Molecular Plant Pathology 19 (2018)2. - ISSN 1464-6722 - p. 257 - 259.
Interaction of a hydophobic weak polyelectrolyte star with an apolar surface
Rudd, O.V. ; Leermakers, F.A.M. ; Birshtein, T.M. - \ 2014
Langmuir 30 (2014)1. - ISSN 0743-7463 - p. 48 - 54.
block-copolymer micelles - amphiphilic multiarm - aqueous-solutions - drug-delivery - brushes - collapse - solvent - ph
We consider star-like polymers with weak, that is, pH-dependent, hydrophobic polyelectrolyte arms. For low ionic strength conditions, a microphase-segregated quasimicellar structure is found, for which the star features a compact apolar core and a charged and swollen corona. This state is jump-like lost when the ionic strength is increased, i.e., at some intermediate ionic strength value. Using numerical self-consistent field modeling, we focus on the adsorption characteristics of these objects onto hydrophobic surfaces as a function of the ionic strength. In the quasimicellar state, the stars are attracted to the surface, albeit that, typically, an adsorption barrier is present. The strongest repulsion is found at intermediate ionic strength, where the star-like molecule is in a single-phase state and the barrier remains modest at both low and high ionic strength cases. Remarkably, it is possible that a star in a single swollen phase state is pushed into the quasimicellar state.
|The role of LysM effectors in fungal fitness
Kombrink, A. ; Rudd, J. ; Valkenburg, D.J. ; Thomma, B.P.H.J. - \ 2013
In: Book of Abstracts 27th Fungal Genetics Conference, Asilomar, Pacific Grove, California, USA, 12-17 March 2013. - - p. 85 - 85.
LysM effector genes are found in the genomes of a wide range of fungal species. The encoded LysM effectors are secreted proteins that contain a varying number of LysM domains, which are carbohydrate-binding modules. Ecp6, secreted by tomato leaf mould fungus Cladosporium fulvum, is the first characterized LysM effector. We demonstrated that Ecp6 specifically binds chitin, the major constituent of fungal cell walls that acts as a microbial-associated molecular pattern (MAMP) and triggers immune responses upon recognition by the host. Ecp6 outcompetes plant receptors for chitin binding, and thus prevents the activation of immune responses. Many fungal genomes, including saprophytes, carry multiple LysM effector genes that share only low sequence conservation and encode a varying number of LysM domains. We speculate that fungal LysM effectors might bind different carbohydrates and exert various functions in fungal fitness. In the fungal wheat pathogen Mycosphaerella graminicola, two LysM effectors were identified. Mg3LysM, but not Mg1LysM, suppresses chitin-induced immune responses in a similar fashion as Ecp6. Interestingly, unlike Ecp6, both Mg1LysM and Mg3LysM inhibit degradation of fungal hyphae by plant chitinases, revealing an additional function for LysM effectors in pathogen virulence. We recently observed that Mg1LysM binds to the bacterial cell wall constituent peptidoglycan. Similarly, a LysM effector from the saprophytic fungus Neurospora crassa showed peptidoglycan binding. We hypothesize that peptidoglycan binding by LysM effectors plays a role in the interaction of fungal species with bacterial competitors. The soil-borne fungal pathogen Verticillium dahliae contains seven LysM effectors genes of which one (Vd2LysM) is induced during tomato infection. Inoculation with two independent knock-out mutants revealed that Vd2LysM is required for full virulence of V. dahliae. However, Vd2LysM does not specifically bind chitin and does not function in a similar fashion as previous characterized LysM effectors. Thus, its function in virulence remains unclear.
The Top 10 fungal pathogens in molecular plant pathology
Dean, R. ; Kan, J.A.L. van; Pretorius, Z.A. ; Hammond-Kosack, K.E. ; Pietro, A. Di; Spanu, P.D. ; Rudd, J.J. ; Dickman, M. ; Kahmann, R. ; Ellis, J. ; Foster, G.D. - \ 2012
Molecular Plant Pathology 13 (2012)4. - ISSN 1464-6722 - p. 414 - 430.
rice-blast fungus - infection structure formation - rust avirulence proteins - powdery mildew fungi - f-sp lycopersici - gene pi-ta - magnaporthe-grisea - fusarium-oxysporum - ustilago-maydis - mycosphaerella-graminicola
The aim of this review was to survey all fungal pathologists with an association with the journal Molecular Plant Pathology and ask them to nominate which fungal pathogens they would place in a ‘Top 10’ based on scientific/economic importance. The survey generated 495 votes from the international community, and resulted in the generation of a Top 10 fungal plant pathogen list for Molecular Plant Pathology. The Top 10 list includes, in rank order, (1) Magnaporthe oryzae; (2) Botrytis cinerea; (3) Puccinia spp.; (4) Fusarium graminearum; (5) Fusarium oxysporum; (6) Blumeria graminis; (7) Mycosphaerella graminicola; (8) Colletotrichum spp.; (9) Ustilago maydis; (10) Melampsora lini, with honourable mentions for fungi just missing out on the Top 10, including Phakopsora pachyrhizi and Rhizoctonia solani. This article presents a short resumé of each fungus in the Top 10 list and its importance, with the intent of initiating discussion and debate amongst the plant mycology community, as well as laying down a bench-mark. It will be interesting to see in future years how perceptions change and what fungi will comprise any future Top 10.
|LysM effectors of fungal plant pathogens contribute to virulence in various manners
Kombrink, A. ; Rudd, J.J. ; Thomma, B. - \ 2012
In: Book of Abstracts 11th European Conference on Fungal Genetics, Marburg, Germany, 30 March – 2 April 2012. - - p. 188 - 188.
PR4.82 LysM effectors of fungal plant pathogens contribute to virulence in various manners Anja Kombrink, Jason J. Rudd, Bart P.H.J. Thomma Laboratory of Phytopathology, Wageningen University, 6708 PB Wageningen, Netherlands LysM effector genes are found in the genomes of a wide range of fungal species. LysM effectors are secreted proteins that contain a varying number of LysM domains and no other recognizable protein domains. LysM domains are carbohydrate-binding modules that occur in various proteins that are produced by a variety of organisms. Ecp6 is the first characterized LysM effector that was isolated from the tomato leaf mould fungus Cladosporium fulvum and that is instrumental for fungal virulence. Carbohydrate binding assays demonstrated that Ecp6 specifically binds chitin, the major constituent of fungal cell walls that acts as microbial-associated molecular pattern (MAMP) that triggers immune responses upon recognition by the host. We demonstrated that the chitinbinding effector Ecp6 can compete with plant receptors for chitin binding, and thus prevents the activation of immune responses. Two orthologues of Ecp6 were identified in the fungal wheat pathogen Mycosphaerella graminicola, of which one suppresses chitin-induced immune responses in a similar fashion as Ecp6. Interestingly, unlike Ecp6, both M. graminicola LysM effectors were able to inhibit degradation of fungal hyphae by plant chitinases. Many fungal genomes carry multiple LysM effector genes that share only low sequence conservation and encode varying LysM domain numbers per molecule. Therefore, we hypothesize that different fungal LysM effectors are likely to bind different carbohydrate substrates, exert other functions, or are active in other stages of the fungal life cycle than plant infection. We will report on our most recent findings on LysM effector substrates and functions.
Analysis of Two in Planta Expressed LysM Effector Homologs from the Fungus Mycosphaerella graminicola Reveals Novel Functional Properties and Varying Contributions to Virulence on Wheat
Marshall, R. ; Kombrink, A. ; Motteram, J. ; Loza-Reyes, E. ; Lucas, J. ; Hammond-Kosack, K.E. ; Thomma, B.P.H.J. ; Rudd, J.J. - \ 2011
Plant Physiology 156 (2011)2. - ISSN 0032-0889 - p. 756 - 769.
cladosporium-fulvum - septoria-tritici - maximum-likelihood - blotch pathogen - innate immunity - protein - resistance - host - tomato - recognition
Secreted effector proteins enable plant pathogenic fungi to manipulate host defenses for successful infection. Mycosphaerella graminicola causes Septoria tritici blotch disease of wheat (Triticum aestivum) leaves. Leaf infection involves a long (approximately 7 d) period of symptomless intercellular colonization prior to the appearance of necrotic disease lesions. Therefore, M. graminicola is considered as a hemibiotrophic (or necrotrophic) pathogen. Here, we describe the molecular and functional characterization of M. graminicola homologs of Ecp6 (for extracellular protein 6), the Lysin (LysM) domain-containing effector from the biotrophic tomato (Solanum lycopersicum) leaf mold fungus Cladosporium fulvum, which interferes with chitin-triggered immunity in plants. Three LysM effector homologs are present in the M. graminicola genome, referred to as Mg3LysM, Mg1LysM, and MgxLysM. Mg3LysM and Mg1LysM genes were strongly transcriptionally up-regulated specifically during symptomless leaf infection. Both proteins bind chitin; however, only Mg3LysM blocked the elicitation of chitin-induced plant defenses. In contrast to C. fulvum Ecp6, both Mg1LysM and Mg3LysM also protected fungal hyphae against plant-derived hydrolytic enzymes, and both genes show significantly more nucleotide polymorphism giving rise to nonsynonymous amino acid changes. While Mg1LysM deletion mutant strains of M. graminicola were fully pathogenic toward wheat leaves, Mg3LysM mutant strains were severely impaired in leaf colonization, did not trigger lesion formation, and were unable to undergo asexual sporulation. This virulence defect correlated with more rapid and pronounced expression of wheat defense genes during the symptomless phase of leaf colonization. These data highlight different functions for MgLysM effector homologs during plant infection, including novel activities that distinguish these proteins from C. fulvum Ecp6.
Finished Genome of the Fungal Wheat Pathogen Mycosphaerella graminicola Reveals Dispensome Structure, Chromosome Plasticity, and Stealth Pathogenesis
Goodwin, S.B. ; M'Barek, S. Ben; Dhillon, B. ; Wittenberg, A.H.J. ; Crane, C.F. ; Hane, J.K. ; Foster, A.J. ; Lee, T.A.J. van der; Grimwood, J. ; Aerts, A. ; Antoniw, J. ; Bailey, A. ; Bluhm, B. ; Bowler, J. ; Bristow, J. ; Burgt, A. van der; Canto-Canché, B. ; Churchill, A.C.L. ; Conde-Ferràez, L. ; Cools, H.J. ; Coutinho, P.M. ; Csukai, M. ; Dehal, P. ; Wit, P.J.G.M. de; Donzelli, B. ; Geest, H.C. van de; Ham, R.C.H.J. van; Hammond-Kosack, K.E. ; Henrissat, B. ; Kilian, A. ; Kobayashi, A.K. ; Koopmann, E. ; Kourmpetis, Y. ; Kuzniar, A. ; Lindquist, E. ; Lombard, V. ; Maliepaard, C.A. ; Martins, N. ; Mehrabi, A. ; Nap, J.P.H. ; Ponomarenko, A. ; Rudd, J.J. ; Salamov, A. ; Schmutz, J. ; Schouten, H.J. ; Shapiro, H. ; Stergiopoulos, I. ; Torriani, S.F.F. ; Tu, H. ; Vries, R.P. de; Waalwijk, C. ; Ware, S.B. ; Wiebenga, A. ; Zwiers, L.H. ; Oliver, R.P. ; Grigoriev, I.V. ; Kema, G.H.J. - \ 2011
Plos Genetics 7 (2011)6. - ISSN 1553-7404 - 17 p.
magnaporthe-grisea - b-chromosomes - gene - host - organization - annotation - resistance - neurospora - expression - symbiosis
The plant-pathogenic fungus Mycosphaerella graminicola (asexual stage: Septoria tritici) causes septoria tritici blotch, a disease that greatly reduces the yield and quality of wheat. This disease is economically important in most wheat-growing areas worldwide and threatens global food production. Control of the disease has been hampered by a limited understanding of the genetic and biochemical bases of pathogenicity, including mechanisms of infection and of resistance in the host. Unlike most other plant pathogens, M. graminicola has a long latent period during which it evades host defenses. Although this type of stealth pathogenicity occurs commonly in Mycosphaerella and other Dothideomycetes, the largest class of plant-pathogenic fungi, its genetic basis is not known. To address this problem, the genome of M. graminicola was sequenced completely. The finished genome contains 21 chromosomes, eight of which could be lost with no visible effect on the fungus and thus are dispensable. This eight-chromosome dispensome is dynamic in field and progeny isolates, is different from the core genome in gene and repeat content, and appears to have originated by ancient horizontal transfer from an unknown donor. Synteny plots of the M. graminicola chromosomes versus those of the only other sequenced Dothideomycete, Stagonospora nodorum, revealed conservation of gene content but not order or orientation, suggesting a high rate of intra-chromosomal rearrangement in one or both species. This observed “mesosynteny” is very different from synteny seen between other organisms. A surprising feature of the M. graminicola genome compared to other sequenced plant pathogens was that it contained very few genes for enzymes that break down plant cell walls, which was more similar to endophytes than to pathogens. The stealth pathogenesis of M. graminicola probably involves degradation of proteins rather than carbohydrates to evade host defenses during the biotrophic stage of infection and may have evolved from endophytic ancestors. Author Summary The plant-pathogenic fungus Mycosphaerella graminicola causes septoria tritici blotch, one of the most economically important diseases of wheat worldwide and a potential threat to global food production. Unlike most other plant pathogens, M. graminicola has a long latent period during which it seems able to evade host defenses, and its genome appears to be unstable with many chromosomes that can change size or be lost during sexual reproduction. To understand its unusual mechanism of pathogenicity and high genomic plasticity, the genome of M. graminicola was sequenced more completely than that of any other filamentous fungus. The finished sequence contains 21 chromosomes, eight of which were different from those in the core genome and appear to have originated by ancient horizontal transfer from an unknown donor. The dispensable chromosomes collectively comprise the dispensome and showed extreme plasticity during sexual reproduction. A surprising feature of the M. graminicola genome was a low number of genes for enzymes that break down plant cell walls; this may represent an evolutionary response to evade detection by plant defense mechanisms. The stealth pathogenicity of M. graminicola may involve degradation of proteins rather than carbohydrates and could have evolved from an endophytic ancestor.
Reproduction, growth, and migration of fishes in a regulated lowland tributary : Potential recruitment to the river Meuse
Pollux, B.J.A. ; Korosi, A. ; Verberk, W.C.E.P. ; Pollux, P.M.J. ; Velde, G. Van Der - \ 2006
Hydrobiologia 565 (2006)1 SPEC. ISS.. - ISSN 0018-8158 - p. 105 - 120.
Juveniles - Larvae - Migration - Nursery - Residents - Transients
Many European rivers are characterized by a canalized main channel, steep stony embankments, the absence of aquatic vegetation, regulated flow dynamics, reduced hydrological connectivity to the floodplains and a lack of spawning and nursery areas for many fish species. In such regulated rivers, tributaries may be particularly important for recruitment of fish populations in the main channel. This paper describes the reproduction, growth and migration of fishes in the Everlose Beek, a regulated lowland tributary stream of the river Meuse (The Netherlands), using bi-weekly sampling from January to December 2002. A total of 8615 fishes were caught, belonging to 13 different species. The fish species were classified into three groups, viz., residents, migrants and transients, based on the presence of various life-stages in the tributary. Size-frequency data suggest that each group uses the Everlose Beek differently: (i) Stone loach (Barbatula barbatula), Gudgeon (Gobio gobio) and Three-spined stickleback (Gasterosteus aculeatus) were resident species using the tributary as a spawning, nursery and adult habitat; (ii) Bream (Abramis brama), Roach (Rutilus rutilus), Rudd (R. erythrophthalmus), Tench (Tinca tinca), and Pike (Esox lucius) were migratory species, using the tributary as a spawning area, as well as a nursery habitat during their first year of growth, but migrating towards the river Meuse typically at a length of 5-15 cm; and (iii) Bleak (Alburnus alburnus), Sunbleak (Leucaspius delineatus), Carp (Cyprinus carpio), Crucian carp (Carassius carassius), and Perch (Perca , fluviatilis) were transient species, characterized by an absence of reproduction, .and the occurrence in very low densities of >age-1 juveniles and adults only. Lowland tributaries, such as the Everlose Beek, can contribute to the recruitment of particularly migrant species, hence contributing to fish populations of the regulated river Meuse.
Presence of lactobacilli in the intestinal content of freshwater fish from a river and from a farm with a recirculation system
Bucio Galindo, A. ; Hartemink, R. ; Schrama, J.W. ; Verreth, J.A.J. ; Rombouts, F.M. - \ 2006
Food Microbiology 23 (2006)5. - ISSN 0740-0020 - p. 476 - 482.
lactic-acid bacteria - identification - flora - l.
Lactobacilli are Gram-positive and catalase negative rods commonly found in lactic acid fermented foods and in the gastrointestinal tract of mammals and birds. Few studies have described lactobacilli in freshwater fish. We analysed the presence of lactobacilli in the intestines of young and adult freshwater fish inhabiting a river environment and from fish reared in an aquaculture unit with a water recirculation system. Various species of lactobacilli were present in relatively high number in the intestines of edible fresh water fish from the river, especially in the warm season but in low numbers in the cold season. Lactobacilli were scarcely found in the intestines of edible farmed fish reared in a recirculation system in warm water. Lactobacilli are reported for the first time from the intestines of wild European eel, perch, rudd, ruffe, bleak, silver bream, chub, somnul and farmed African catfish. The two first fishes, and the last one are highly valuable species for fisheries and aquaculture. Additionally, improved methods for storage and bacteriological analysis of fish intestinal content are described. The natural presence of lactic acid bacteria in fish may be of great interest in producing fermented fish products worldwide
An institutional framework for designing and monitoring ecosystem-based fisheries management policy experiments
Rudd, M.A. - \ 2004
Ecological Economics 48 (2004)1. - ISSN 0921-8009 - p. 109 - 124.
integrated coastal management - marine capture fisheries - sustainable development - indicators - performance - governance - principles - guidelines - progress
Indicator systems are seen as central tools for ecosystem-based fisheries management, helping to steer fisheries towards sustainability by providing timely and useful information to decision-makers. Without testing hypotheses about the links between policies and outcomes, however, indicator systems may do little more than promote ad hoc policies, possibly even prolonging the transition to sustainable fisheries. The Institutional Analysis and Development (IAD) framework is a robust framework that has been used extensively to design policy experiments and empirically test theories and models linking ecological–economic systems, institutions and the sustainability of common pool resource systems. A modified IAD framework is developed that transparently encompasses both process-oriented pressure-state-response (PSR) and structurally oriented sustainable livelihood indicator frameworks, thus providing a platform for ecosystem-based fisheries management policy experiment design and monitoring. An institutional approach to fisheries management facilitates critical examination of important cross-cutting issues, including assumptions regarding what comprises sustainability and how market, government and civil society organizations use strategic investments in capital assets and institutions to achieve sustainability objectives. The emphasis on capital assets keeps attention on the relative merits of alternative investment options in policy experiments.
Institutional analysis of marine reserves and fisheries governance policy experiments : a case study of Nassau grouper conservation in the Turks and Caicos Islands
Rudd, M.A. - \ 2003
Wageningen University. Promotor(en): Henk Folmer; Kees van Kooten. - Wageningen : Wageningen Universiteit - ISBN 9789058088994 - 274
visserijbeheer - ecosystemen - milieubescherming - turks- en caicoseilanden - natuurreservaten - mariene gebieden - beschermingsgebieden - economische analyse - zeevisserij - ecosysteemdiensten - zeereservaten - fishery management - ecosystems - economic analysis - nature conservation - environmental protection - turks and caicos islands - marine areas - conservation areas - marine fisheries - ecosystem services - marine protected areas
Keywords: Ecosystem-based fisheries management; marine reserves; marine protected areas; social capital; institutional analysis; Turks and Caicos Islands; Nassau grouper Many tropical fisheries around the world are in crisis because of the depletion of valuable reef species and the destruction of habitat upon which they depend. The complexity of reef fisheries and lack of management resources in southern nations limit the potential effectiveness of policies that focus on single species. As a result, ecosystem-based fisheries management is increasingly viewed as the only real alternative for managing these tropical reef fisheries. There is a widely held view that the devolution of management power from central government managers to local communities is central to the ecosystem-based fisheries management process and that marine reserves are the primary tool by which to implement ecosystem-based fisheries management. Marine reserves can protect or enhance multiple ecosystem services simultaneously and arguments are often made that they are more cost-effective than other management options because they are easy to monitor and enforce. The first theoretically-oriented part of this research emphasizes the role that social capital - the norms, networks and governance infrastructure that facilitates mutually advantageous collective action - plays in ecosystem-based fisheries management. In the second part of the research, I illustrate the utility of taking an institutional analysis approach to ecosystem-based fisheries management policy by examining the case of Nassau grouper (Epinephelus striatus) conservation and fisheries management in the Turks and Caicos Islands. While the focus of this case study is a single, small island nation, I believe that the results - that there are substantial incentives for private sector and government actors to oppose implementation of marine reserves - have broader relevance in the debate over the use of marine reserves for tropical fisheries management and conservation. Marine reserves are widely viewed as cost-effective, all-purpose tools for fisheries enhancement and conservation, yet my results suggest that there are policy alternatives - in this case, a commercial trade ban on Nassau grouper in tourist-oriented restaurants - that are much more likely to be effectively implemented and that should be substantially more cost-effective than marine reserves. Market-oriented policy tools should not be under-emphasized in ecosystem-based fisheries management. In instances where local social capital is lacking, they may actually have a higher likelihood of achieving conservation objectives and be more cost-effective than poorly supported marine reserves or `paper parks`.
|Accounting for the impacts of fishers' knowledge and norms on economic efficiency
Rudd, M.A. - \ 2003
In: Putting Fishers' knowledge to work. - Vancouver : Fisheries Centre, University of British Columbia, Canada - p. 138 - 147.
Policy analysis for tropical marine reserves: challenges and directions
Rudd, M.A. ; Tupper, M.H. ; Folmer, H. ; Kooten, G.C. van - \ 2003
Fish and Fisheries 4 (2003)1. - ISSN 1467-2960 - p. 65 - 85.
coral-reef fish - caribbean spiny lobster - protected areas - fisheries management - sustainable governance - population regulation - resources management - density-dependence - coastal fisheries - collective action
Marine reserves are considered to be a central tool for marine ecosystem-based management in tropical inshore fisheries. The arguments supporting marine reserves are often based on both the nonmarket values of ecological amenities marine reserves provide and the pragmatic cost-saving advantages relating to reserve monitoring and enforcement. Marine reserves are, however, only one of a suite of possible policy options that might be used to achieve conservation and fisheries management objectives, and have rarely been the focus of rigorous policy analyses that consider a full range of economic costs and benefits, including the transaction costs of management. If credible analyses are not undertaken, there is a danger that current enthusiasm for marine reserves may wane as economic performance fails to meet presumed potential. Fully accounting for the value of ecological services flowing from marine reserves requires consideration of increased size and abundance of focal species within reserve boundaries, emigration of target species from reserves to adjacent fishing grounds, changes in ecological resilience, and behavioural responses of fishers to spatially explicit closures. Expanding policy assessments beyond standard cost-benefit analysis (CBA) also requires considering the impact of social capital on the costs of managing fisheries. In the short term, the amount of social capital that communities possess and the capacity of the state to support the rights of individuals and communities will affect the relative efficiency of marine reserves. Reserves may be the most efficient policy option when both community and state capacity is high, but may not be when one and/or the other is weak. In the longer term, the level of social capital that a society possesses and the level of uncertainty in ecological and social systems will also impact the appropriate level of devolution or decentralization of fisheries governance. Determining the proper balance of the state and the community in tropical fisheries governance will require broad comparative studies of marine reserves and alternative policy tools.
|Developing a spatially explicit agent-based model of queen conch distribution in a Marine Protected Area in the Turks and Caicos Islands
Rudd, M.A. ; Railsback, S. ; Danylchuk, A. ; Clerveaux, W. - \ 2002
In: Proceedings of the Gulf Caribbean Fisheries Institute. - Marathon, Florida, USA : GCFI - p. 259 - 271.
|Size-dependent habitat use of juvenile queen conch (Strombus gigas) in East Harbour Lobster and Conch Reserve, Turks and Caicos Islands, BWI
Danylchuk, A. ; Rudd, M.A. ; Giles, I. ; Baldwin, K. - \ 2002
In: Proceedings of the Gulf Caribbean Fisheries Institute. - Marathon, Florida, USA : GCFI - p. 241 - 249.
Species-specific impacts of a small marine reserve on reef fish production and fishing productivity in the Turks and Caicos Islands
Tupper, M.H. ; Rudd, M.A. - \ 2002
Environmental Conservation 29 (2002)4. - ISSN 0376-8929 - p. 484 - 492.
Marine reserves are widely considered to potentially benefit reef fisheries through emigration, yet the empirical basis for predicting the extent of this for small reserves is weak. The effects of fishing pressure and habitat on biomass and catch per unit effort (CPUE) of three species of exploited reef fish were studied at South Caicos, Turks and Caicos Islands. Distribution and abundance of hogfish (Lachnolaimus maximus) and white margate (Haemulon album) were inversely correlated with cover of fleshy macroalgae. Nassau grouper (Epinephelus striatus) were positively associated with vertical relief, but were unaffected by algal cover. Mean size, density, and biomass of hogfish were higher in a small (4 km sup2) marine reserve than on fished reefs, as was biomass of white margate. CPUE of hogfish was inversely related to distance from the centre of the reserve, suggesting that spillover of this species from the reserve to adjacent reefs may enhance local yields, possibly providing economic incentives for fishers to comply with reserve regulations. Fishing pressure, however, had no apparent effect on Nassau grouper. Larger fishes and those that migrate to spawn, such as economically valuable Nassau grouper, may move over too large a range to be effectively protected by small marine reserves. Small reserves may not protect all fish, but they can increase the biomass of smaller or more sedentary reef fishes and may be a useful tool for the conservation or management of species such as hogfish. Other policy options, such as seasonal spawning closures or total allowable catches, need to be considered for larger, more mobile fishes in the Turks and Caicos Islands.
The impact of Nassau grouper size and abundance on scuba diver site selection and MPA economics
Rudd, M.A. ; Tupper, M.H. - \ 2002
Coastal Management 30 (2002)2. - ISSN 0892-0753 - p. 133 - 151.
Since many fisheries are size-selective, the establishment of marine protected areas (MPAs) is expected to increase both the average size and abundance of exploited species, such as the valuable but vulnerable Nassau grouper ( Epinephelus striatus ). Increases in mean size and/or abundance of protected species within MPAs may also provide nonextractive economic value to recreationalists. In this research, we assessed scuba diver preferences for viewing Nassau grouper and the marginal tradeoffs that divers exhibited between fish size and abundance and between dive group size and price in the Turks and Caicos Islands. We used results from a paired comparison conjoint survey to develop market share simulations of dive site choice. Market shares increased significantly for sites with increased Nassau grouper abundance and mean size. This implies that Nassau groupers provide nonextractive economic value to divers. Our results suggest that accounting for the nonextractive value of increased fish abundance and size may influence the economic viability of MPAs.