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Ovando D.A.,University of California at Santa Barbara | Deacon R.T.,University of California at Santa Barbara | Lester S.E.,University of California at Santa Barbara | Costello C.,University of California at Santa Barbara | And 8 more authors.
Marine Policy | Year: 2013

Cooperatives are increasingly proposed as solutions for sustainable fisheries management. While individual case studies and economic theory suggest that cooperatives may manage fisheries effectively under some conditions, there is little empirical evidence comparing the actions of cooperative fisheries across a diverse set of environments. This study applies a standardized survey method to collect data from a set of cooperatively managed fisheries from around the globe, documenting their social, economic, and ecological settings as well as the cooperative behaviors in which they engage and the role they play in conservation. The resulting database covers 67 cooperatives from the major oceanic regions of the world, providing a unique overview of the global diversity of fishery cooperatives. It enables empirical analysis of the links between the characteristics and contexts of fisheries, such as the development status of the host nation, fisheries management practices, and species characteristics, and the collective actions taken by fishery cooperatives. The evidence shows that cooperatives form in a variety of development and governance contexts, and in diverse kinds of fisheries. Fishery cooperatives often take actions directed toward coordinating harvest activities, adopting and enforcing restrictions on fishing methods and effort, and taking direct conservation actions such as establishment of private marine protected areas. © 2012 Elsevier Ltd. Source


Tamme R.,University of Tartu | Hiiesalu I.,University of Tartu | Laanisto L.,University of Tartu | Laanisto L.,CSIC - National Museum of Natural Sciences | And 3 more authors.
Journal of Vegetation Science | Year: 2010

The positive relationship between spatial environmental heterogeneity and species diversity is a widely accepted concept, generally associated with niche limitation. However, niche limitation cannot account for negative heterogeneity-diversity relationships (HDR) revealed in several case studies. Here we explore how HDR varies at different spatial scales and provide novel theories for small-scale species co-existence that explain both positive and negative HDR. At large spatial scales of heterogeneity (e.g. landscape level), different communities co-exist, promoting large regional species pool size and resulting in positive HDR. At smaller scales within communities, species co-existence can be enhanced by increasing the number of different patches, as predicted by the niche limitation theory, or alternatively, restrained by heterogeneity. We conducted meta-regressions for experimental and observational HDR studies, and found that negative HDRs are significantly more common at smaller spatial scales. We propose three theories to account for niche limitation at small spatial scales. (1) Microfragmentation theory: with increasing spatial heterogeneity, large homogeneous patches lose area and become isolated, which in turn restrains the establishment of new plant individuals and populations, thus reducing species richness. (2) Heterogeneity confounded by mean: when heterogeneity occurs at spatial scales smaller than the size of individual plants, which forage through the patches, species diversity can be either positively or negatively affected by a change in the mean of an environmental factor. (3) Heterogeneity as a separate niche axis: the ability of species to tolerate heterogeneity at spatial scales smaller than plant size varies, affecting HDR. We conclude that processes other than niche limitation can affect the relationship between heterogeneity and diversity. © 2010 International Association for Vegetation Science. Source


Wood C.L.,Stanford University | Micheli F.,Stanford University | Fernandez M.,University of Santiago de Chile | Gelcich S.,University of Santiago de Chile | And 3 more authors.
Journal of Animal Ecology | Year: 2013

Parasites comprise a substantial proportion of global biodiversity and exert important ecological influences on hosts, communities and ecosystems, but our knowledge of how parasite populations respond to human impacts is in its infancy. Here, we present the results of a natural experiment in which we used a system of highly successful marine protected areas and matched open-access areas in central Chile to assess the influence of fishing-driven biodiversity loss on parasites of exploited fish and invertebrate hosts. We measured the burden of gill parasites for two reef fishes (Cheilodactylus variegatus and Aplodactylus punctatus), trematode parasites for a keyhole limpet (Fissurella latimarginata), and pinnotherid pea crab parasites for a sea urchin (Loxechinus albus). We also measured host density for all four hosts. We found that nearly all parasite species exhibited substantially greater density (# parasites m-2) in protected than in open-access areas, but only one parasite species (a gill monogenean of C. variegatus) was more abundant within hosts collected from protected relative to open-access areas. These data indicate that fishing can drive declines in parasite abundance at the parasite population level by reducing the availability of habitat and resources for parasites, but less commonly affects the abundance of parasites at the infrapopulation level (within individual hosts). Considering the substantial ecological role that many parasites play in marine communities, fishing and other human impacts could exert cryptic but important effects on marine community structure and ecosystem functioning via reductions in parasite abundance. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society. Source


Zobel M.,University of Tartu | Otto R.,University of La Laguna | Laanisto L.,University of Tartu | Laanisto L.,CSIC - National Museum of Natural Sciences | And 4 more authors.
Global Ecology and Biogeography | Year: 2011

Aim Explanations of biogeographic diversity patterns have emphasized the role of large-scale processes that determine species pools, whereas explanations of local patterns have not. We address the hypothesis that local diversity patterns are also primarily dependent on the size of the available species pools, which are expected to be large when the particular habitat type has been evolutionary more abundant, or in unproductive habitats due to shorter generation time and hence higher diversification rates. Location The Canary Islands. Methods We determined the geographic distribution and habitat requirements of all native vascular plant species in the Canary Islands. Species pools for each habitat type on particular islands were further split into two categories according to origin: either originating due to local diversification or due to natural immigration. The dependence of historical diversification and diversification rate on habitat type, area, age, altitude and distance to the mainland was tested with general linear mixed models weighed according to the Akaike information criterion. Results The largest portion of the local variation in plant species diversity was attributed to the historic (pre-human) habitat area, although island age was also important. The diversification rate was higher in unproductive habitats of coastal scrub and summit vegetation. Main conclusion Our study supports the species pool hypothesis, demonstrating that natural local patterns of species diversity in different habitats mirror the abundance of those particular habitats in evolutionary history. It also supports the community-level birth rate hypothesis, claiming that stressful conditions result in higher diversification rates. We conclude that much of the observed local variation in plant diversity can be attributed to the differing sizes of species pools evolved under particular habitat conditions, and that historic parameters are far more important determinants of local diversity than suggested by ecological theory. © 2010 Blackwell Publishing Ltd. Source


Troncoso-Palacios J.,University of Chile | Ferri-Yanez F.,CSIC - National Museum of Natural Sciences | Ferri-Yanez F.,Laboratorio Internacional en Cambio Global
Check List | Year: 2013

We report two new records for Liolaemus patriciaiturrae in Chile, one corresponding to specimens previously misidentified as L. nigriceps. We also provide a map showing all the known locations of the species. © 2013 Check List and Authors. Source

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