37 research outputs found

    Rockfish size and age: The crossroads of spatial protection, central place fisheries and indigenous rights

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    AbstractIndigenous people harvest wild species for food and cultural practice, fundamentally linking biodiversity conservation and indigenous rights. Rockfishes (Sebastes spp.) are culturally significant to indigenous people (or First Nations) of coastal British Columbia (BC), Canada, who regulate their harvest under traditional governance structures. First Nations elders, however, have observed a decline in the body sizes and abundance of rockfishes, which coincides with increased exploitation by non-indigenous fishers. Rockfishes are vulnerable to overexploitation because fecundity and offspring quality increase with maternal size or age, yet fisheries truncate size and age structure. During 2006, 2007 and 2013–2015, we worked with the Wuikinuxv, Nuxalk, Heiltsuk and Kitasoo/Xai’Xais First Nations of BC’s Central Coast, examining rockfish population characteristics at 282 of their fishing sites. We used hook-and-line gear to collect fishery independent data, and sampled landings from First Nations subsistence fishers. Spatial fishery closures served as experimental treatments. We also applied central place foraging theory to predict declines in size, age and abundance with increasing distance from recreational fishing lodges and other ports. Analyses used linear mixed models and controlled for environmental variables. Our results suggest that spatial closures for commercial and recreational fishers led to greater size and abundance of some, but not all rockfishes, possibly due to interspecific differences in the extent to which closures contain suitable habitat, effects of non-compliance, or other factors. Notably, Yelloweye Rockfish (Sebastes ruberrimus), a species key to indigenous diets, were 21% larger inside than outside spatial closures. Possibly reflecting cumulative fishery exploitation, however, old-aged Yelloweye Rockfish were rare. Fishery impacts on size and relative abundance decreased at sites that required longer travel times and greater fuel costs for recreational fishers to exploit, but only for the longest-lived species (size responses) and for long-lived species analysed in aggregate (abundance responses). Measures for protecting indigenous access to rockfishes include evaluation of habitat suitability and compliance within spatial closures, improved understanding of recreational fishery impacts, and treating old-age and large size structures as explicit management objectives. Our study contributes to a global effort to integrate indigenous cultural values with biological conservation

    Bottom-Up Forcing And The Decline of Steller Sea Lions (Eumetopias jubatus) In Alaska: Assessing The Ocean Climate Hypothesis

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    Declines of Steller sea lion ( Eumetopias jubatus) populations in the Aleutian Islands and Gulf of Alaska could be a consequence of physical oceanographic changes associated with the 1976–77 climate regime shift. Changes in ocean climate are hypothesized to have affected the quantity, quality, and accessibility of prey, which in turn may have affected the rates of birth and death of sea lions. Recent studies of the spatial and temporal variations in the ocean climate system of the North Pacific support this hypothesis. Ocean climate changes appear to have created adaptive opportunities for various species that are preyed upon by Steller sea lions at mid-trophic levels. The east–west asymmetry of the oceanic response to climate forcing after 1976–77 is consistent with both the temporal aspect (populations decreased after the late 1970s) and the spatial aspect of the decline (western, but not eastern, sea lion populations decreased). These broad-scale climate variations appear to be modulated by regionally sensitive biogeographic structures along the Aleutian Islands and Gulf of Alaska, which include a transition point from coastal to open-ocean conditions at Samalga Pass westward along the Aleutian Islands. These transition points delineate distinct clusterings of different combinations of prey species, which are in turn correlated with differential population sizes and trajectories of Steller sea lions. Archaeological records spanning 4000 yr further indicate that sea lion populations have experienced major shifts in abundance in the past. Shifts in ocean climate are the most parsimonious underlying explanation for the broad suite of ecosystem changes that have been observed in the North Pacific Ocean in recent decades. [ABSTRACT FROM AUTHOR] Copyright of Fisheries Oceanography is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder\u27s express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.

    A function-based typology for Earth’s ecosystems

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    As the United Nations develops a post-2020 global biodiversity framework for the Convention on Biological Diversity, attention is focusing on how new goals and targets for ecosystem conservation might serve its vision of ‘living in harmony with nature’(1,2). Advancing dual imperatives to conserve biodiversity and sustain ecosystem services requires reliable and resilient generalizations and predictions about ecosystem responses to environmental change and management(3). Ecosystems vary in their biota(4), service provision(5) and relative exposure to risks(6), yet there is no globally consistent classification of ecosystems that reflects functional responses to change and management. This hampers progress on developing conservation targets and sustainability goals. Here we present the International Union for Conservation of Nature (IUCN) Global Ecosystem Typology, a conceptually robust, scalable, spatially explicit approach for generalizations and predictions about functions, biota, risks and management remedies across the entire biosphere. The outcome of a major cross-disciplinary collaboration, this novel framework places all of Earth’s ecosystems into a unifying theoretical context to guide the transformation of ecosystem policy and management from global to local scales. This new information infrastructure will support knowledge transfer for ecosystem-specific management and restoration, globally standardized ecosystem risk assessments, natural capital accounting and progress on the post-2020 global biodiversity framework

    Corporate environmentalism and the reclamation of dormant properties : Giant Nickel, a case study

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    Mining companies occasionally, through acquisition or purchase, inherit old mining sites. These mining sites may contain exploration potential or the potential for new mine development, and most contain environmental liabilities. This paper describes how one company has evaluated their property holdings and, where the potential for further exploration or development is remote, has developed a strategy for reducing liability by reclaiming these dormant facilities. Citing the example of the Giant Nickel property, located near Hope, B.C., Homestake Canada Inc's reclamation strategy will be followed from the first stage of site assessment, hazard identification, and reclamation work scheduling, through reclamation activities at the site, including the reclamation of the mill site and tailings ponds, closure of all workings open to the surface and the disposition of a collapsed crown pillar. This paper will also outline the steps taken to ensure that the reclamation work effectively accomplished the goals of the reclamation strategy.Non UBCUnreviewedOthe

    Fisheries Centre research reports, Vol. 16, no. 6

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    DIRECTOR’S FOREWORD. ABSTRACT. INTRODUCTION. METHODS. RESULTS. Chlorophyll. Sea surface temperature. SST slope. Sea level anomaly. Surface wind speed. climatologies. ROMS model output. DISCUSSION. ACKNOWLEDGEMENTS. REFERENCES. APPENDICES. Appendix 1 – Data sets prepared for economic and habitat studies of the eastern North Pacific / Bering Sea. Appendix 2 – Federal Geographic Data Committee compatible metadata.Fisheries Centre (FC)UnreviewedFacultyResearcherGraduat

    Data from: Why less complexity produces better forecasts: an independent data evaluation of kelp habitat models

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    Understanding how species are distributed in the environment is increasingly important for natural resource management, particularly for keystone and habitat forming species, and those of conservation concern. Habitat suitability models are fundamental to developing this understanding; however their use in management continues to be limited due to often-vague model objectives and inadequate evaluation methods. Along the Northeast Pacific coast, canopy kelps (Macrocystis pyrifera and Nereocystis luetkeana) provide biogenic habitat and considerable primary production to nearshore ecosystems. We investigated the distribution of these species by examining a series of increasingly complex habitat suitability models ranging from process-based models based on species' ecology to complex Generalised Additive Models applied to purpose-collected survey data. Seeking limits on model complexity, we explored the relationship between model complexity and forecast skill, measured using both cross-validation and independent data evaluation. Our analysis confirmed the importance of predictors used in models of coastal kelp distributions developed elsewhere (i.e., depth, bottom type, bottom slope, and exposure); it also identified additional important factors including salinity, and interactions between exposure and salinity, and slope and tidal energy. Comparative results showed that cross-validation can lead to over-fitting, while independent data evaluation clearly identified the appropriate model complexity for generating habitat forecasts. Our results also illustrate that, depending on the evaluation data, predictions from simpler models can out-perform those from more complex models. Collectively, the insights from evaluating multiple models with multiple data sets contribute to the holistic assessment of model forecast skill. The continued development of methods and metrics for evaluating model forecasts with independent data, and the explicit consideration of model objectives and assumptions, promise to increase the utility of model forecasts to decision makers

    Why less complexity produces better forecasts: An independent data evaluation of kelp habitat models

    No full text
    Understanding how species are distributed in the environment is increasingly important for natural resource management, particularly for keystone and habitat forming species, and those of conservation concern. Habitat suitability models are fundamental to developing this understanding; however their use in management continues to be limited due to often-vague model objectives and inadequate evaluation methods. Along the Northeast Pacific coast, canopy kelps (Macrocystis pyrifera and Nereocystis luetkeana) provide biogenic habitat and considerable primary production to nearshore ecosystems. We investigated the distribution of these species by examining a series of increasingly complex habitat suitability models ranging from process-based models based on species' ecology to complex Generalised Additive Models applied to purpose-collected survey data. Seeking limits on model complexity, we explored the relationship between model complexity and forecast skill, measured using both cross-validation and independent data evaluation. Our analysis confirmed the importance of predictors used in models of coastal kelp distributions developed elsewhere (i.e., depth, bottom type, bottom slope, and exposure); it also identified additional important factors including salinity, and interactions between exposure and salinity, and slope and tidal energy. Comparative results showed that cross-validation can lead to over-fitting, while independent data evaluation clearly identified the appropriate model complexity for generating habitat forecasts. Our results also illustrate that, depending on the evaluation data, predictions from simpler models can out-perform those from more complex models. Collectively, the insights from evaluating multiple models with multiple data sets contribute to the holistic assessment of model forecast skill. The continued development of methods and metrics for evaluating model forecasts with independent data, and the explicit consideration of model objectives and assumptions, promise to increase the utility of model forecasts to decision makers

    Why less complexity produces better forecasts : An independent data evaluation of kelp habitat models

    No full text
    Understanding how species are distributed in the environment is increasingly important for natural resource management, particularly for keystone and habitat forming species, and those of conservation concern. Habitat suitability models are fundamental to developing this understanding; however their use in management continues to be limited due to often-vague model objectives and inadequate evaluation methods. Along the Northeast Pacific coast, canopy kelps {Macrocystis pyrifera and Nereocystis luetkeana) provide biogenic habitat and considerable primary production to nearshore ecosystems. We investigated the distribution of these species by examining a series of increasingly complex habitat suitability models ranging from process-based models based on species' ecology to complex Generalised Additive Models applied to purpose-collected survey data. Seeking limits on model complexity, we explored the relationship between model complexity and forecast skill, measured using both cross-validation and independent data evaluation. Our analysis confirmed the importance of predictors used in models of coastal kelp distributions developed elsewhere {i.e., depth, bottom type, bottom slope, and exposure); it also identified additional important factors including salinity, and interactions between exposure and salinity, and slope and tidal energy. Comparative results showed that cross-validation can lead to over-fitting, while independent data evaluation clearly identified the appropriate model complexity for generating habitat forecasts. Our results also illustrate that, depending on the evaluation data, predictions from simpler models can out-perform those from more complex models. Collectively, the insights from evaluating multiple models with multiple data sets contribute to the holistic assessment of model forecast skill. The continued development of methods and metrics for evaluating model forecasts with independent data, and the explicit consideration of model objectives and assumptions, promise to increase the utility of model forecasts to decision makers.Science, Faculty ofNon UBCResources, Environment and Sustainability (IRES), Institute forReviewedFacult
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