Matching Items (8)

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Effects of Net Illumination on Fish Assemblages in Baja California Sur, Mexico

Description

Globally, the incidental capture of non-target species in fisheries (bycatch) has been linked to declines of ecologically, economically, and culturally important marine species. Gillnet fisheries have especially high bycatch due

Globally, the incidental capture of non-target species in fisheries (bycatch) has been linked to declines of ecologically, economically, and culturally important marine species. Gillnet fisheries have especially high bycatch due to their non-selective nature, necessitating the development of new bycatch reduction technologies (BRTs). Net illumination is an emerging BRT that has shown promise in reducing bycatch of marine megafauna, including sea turtles, cetaceans, and seabirds. However, little research has been conducted to understand the effects of net illumination on fish assemblages, including bony fish and elasmobranchs (i.e. sharks, rays, and skates). Here, I assessed a 7-year dataset of paired net illumination trials using four different types of light (green LEDs, green chemical glowsticks, ultraviolet (UV) lights, and orange lights) to examine the effects of net illumination on fish catch and bycatch in a gillnet fishery at Baja California Sur, Mexico. Analysis revealed no significant effect on bony fish target catch or bycatch for any light type. There was a significant decrease in elasmobranch bycatch using UV and orange lights, with orange lights showing the most promise for decreasing elasmobranch bycatch, resulting in a 50% reduction in bycatch rates. Analysis of the effects of net illumination on elasmobranch target catch was limited due to insufficient data. These results indicate that the illumination of gillnets may offer a practical solution for reducing fish bycatch while maintaining target catch. More research should be conducted to understand the effects of net illumination in different fisheries, how net illumination affects fisher profit and efficiency, and how net illumination affects fish behavior. Further optimization of net illumination is also necessary before the technology can be recommended on a broader scale.

Contributors

Agent

Created

Date Created
  • 2021-05

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Flame retardant contamination in seafood and its significance for conservation

Description

Consumption of seafood poses a substantial threat to global biodiversity. Chemical contamination found in both wild-caught and farmed seafood also presents significant health risks to consumers. Flame retardants, used in

Consumption of seafood poses a substantial threat to global biodiversity. Chemical contamination found in both wild-caught and farmed seafood also presents significant health risks to consumers. Flame retardants, used in upholstery, plastics, clothing, and other products to reduce fire danger, are of particular concern as they are commonly found in the marine environment and permeate the tissues of fish that are sold for consumption via multiple pathways. By summarizing various metrics of sustainability and the mercury content in consumed species of fish and shellfish, researchers have found that high levels of chemical contamination was linked with lesser fishery sustainability. I conducted a literature review of flame retardant content in seafood to further compare contamination and sustainability in addition to the initial analysis with mercury. My review suggests that the widespread issue of fishery collapse could be alleviated by demonstrating to stakeholders that many unsustainable fish stocks are mutually disadvantageous for both human consumers and the environment. Future research should address the need for the collection of data that better represent actual global contaminant concentrations in seafood.

Contributors

Agent

Created

Date Created
  • 2014-05

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Comparing Two Methods of Private Conservation

Description

The purpose of this thesis is to compare ecolabeling to conservation easements for facilitating multi-use land between food production and conservation. Biodiversity has been on the decline as human agriculture

The purpose of this thesis is to compare ecolabeling to conservation easements for facilitating multi-use land between food production and conservation. Biodiversity has been on the decline as human agriculture uses more land. According to Encyclopedia Britannica “Half of the world’s habitable land (some 51 million square km [19.7 million square miles]) has been converted to agriculture, and some 77 percent of agricultural land (some 40 million square km [15.4 million square miles]) is used for grazing by cattle, sheep, goats, and other livestock. This massive conversion of forests, wetlands, grasslands, and other terrestrial ecosystems has produced a 60 percent decline (on average) in the number of vertebrates worldwide since 1970”(Rafferty 2010). The purpose of this paper is to explore ways individual landowners and private businesses can continue to operate profitably on their land while reversing the harmful loss to biodiversity observed in the past 50 years. Two of the most popular methods of achieving conservation on workable land are ecolabeling and conservation easements.

Contributors

Created

Date Created
  • 2020-12

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Fish consumption advisory programs: Opportunities and challenges for the protection of human health in Canada and the US

Description

Fish consumption advisories are important to the protection of human health but are not often widely communicated nor systematically or comprehensively conducted. The objective of this thesis is to explore

Fish consumption advisories are important to the protection of human health but are not often widely communicated nor systematically or comprehensively conducted. The objective of this thesis is to explore the strengths and weaknesses of current fish consumption advisory programs in the US and Canada, providing a comparison between the two countries. The US and Canada were chosen because the two countries are relatively similar in socio-economic makeup as well as in their state vs. federal regulatory setup, allowing for easier comparison. At the sub-federal level, Arizona was chosen to serve as a case study for the US, and Nova Scotia as a case study for Canada. To compare each country, fish consumption advisory programs were broadly described across the 50 US states and 13 Canadian provinces and territories to provide a full understanding of the variation in such programs within each country. In addition to comparison across states and provinces, opportunities and challenges for policy correction to strengthen fish consumption advisory programs will be provided, including suggestions on how the US and Canada can learn from each other in creating better environmental policy. Policy is addressed as a means of improving fish consumption advisory programs because without state or federal requirements to monitor fish tissue for contaminants of concern across the US and Canada, there is no guarantee human health and environmental justice will remain protected in either country. Potential global sources of enhanced environmental policy will be provided as examples of further opportunities for the US and Canada to improve fish consumption advisory program policies.

Contributors

Agent

Created

Date Created
  • 2020-12

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Going beyond paper parks in marine conservation: the role of institutions and governance of marine reserves in the Gulf of California, Mexico

Description

In the face of increasing anthropogenic threats to marine systems, marine reserves

have become a popular tool to promote sustainable fisheries management and protect marine biodiversity. However, the governance structures that

In the face of increasing anthropogenic threats to marine systems, marine reserves

have become a popular tool to promote sustainable fisheries management and protect marine biodiversity. However, the governance structures that determine marine reserve success are not well understood. The response of resource users to reserve establishment, as well as the socioeconomic, institutional, and political contexts in which they occur, are rarely considered during reserve implementation. I use the Coupled Infrastructure Systems (CIS) framework to better understand the interdependencies between social, economic, natural, and institutional processes affecting reserve implementation and performance efficacy in the Gulf of California, Mexico. I used a combination of interviews, qualitative case study comparisons, and systematic conservation planning tools to evaluate the role of different infrastructures, institutions, and governance for marine reserve efficacy in the Gulf of California, Mexico. At a local scale, I assessed stakeholder perceptions, preferences, and knowledge on reserves in the Midriff Islands sub-region of the Gulf. My results show differences in fisher perceptions about the use of reserves for biodiversity conservation and fisheries management, misconceptions about their location, and non-compliance behavior problems. At the regional scale, I explored the trajectories of reserve implementation and performance. I show that capacity-building programs and effective collaboration between non-profit organizations, environmental, fisheries, and other government authorities are essential to coordinate efforts leading to the provisioning of infrastructure that enables effective marine reserves. Furthermore, these programs help facilitate the incorporation of fishers into diversified management and economic activities. Infrastructure provision tradeoffs should be carefully balanced for designing scientifically-sound reserves that can achieve fisheries recovery objectives and incorporating stakeholder engagement processes during the planning phase that allow fishers to include their preferences in a way that complements proposed reserve network solutions. Overall, my results highlight the importance of multiple infrastructures in understanding the dynamics of interacting action situations at various stages of marine reserve implementation and operation. I identify strengths and weaknesses within marine reserve systems that help understand what combinations of infrastructures can be influenced to increase marine reserve effectiveness and robustness to internal and external challenges, as well as delivering benefits for both nature and people.

Contributors

Agent

Created

Date Created
  • 2017

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Flame retardant chemical contamination of seafood, ecologically sustainable fisheries, and significance for biodiversity conservation

Description

Consumption of seafood poses a substantial threat to global biodiversity. Chemical contamination found in both wild-caught and farmed seafood also presents significant health risks to consumers. Flame retardants, used in

Consumption of seafood poses a substantial threat to global biodiversity. Chemical contamination found in both wild-caught and farmed seafood also presents significant health risks to consumers. Flame retardants, used in textiles, upholstery, plastics, and other products to reduce risk of fire-related injury, are of particular concern as they are commonly found in the marine environment and permeate the tissues of fish that are sold for consumption via multiple pathways. The widespread issue of fishery collapse could be alleviated by demonstrating to stakeholders that many unsustainable fish stocks are also unhealthy and mutually disadvantageous for both human consumers and the environment. To thoroughly investigate the confounding factors and contradictory signals enmeshed in the relationship between ecologically sustainable fisheries and flame retardant contamination, I examined the biological characteristics of regional fish stocks which drive both contamination and perceived sustainability. I found that the biological and spatial aspects of commonly consumed aquatic and marine species best predict contamination when compared with various indices of sustainability. My results confirm that knowledge of flame retardant toxicity will become increasingly more important to consumers because a high percentage of global populations rely on coastal seafood for subsistence, and although dispersal of chemical contamination is still a poorly understood phenomenon, fish harvested closer to land are likely to contain higher concentrations of potentially harmful chemicals. Because some of the same biological traits which facilitate the uptake of chemicals also contribute to how a species responds to fishing pressures, concern for private health increases public consideration for the conservation of species at risk.

Contributors

Agent

Created

Date Created
  • 2015

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From policy instruments to action arenas: toward robust fisheries and adaptive fishing households in southwest Nova Scotia

Description

The coastal fishing community of Barrington, Southwest Nova Scotia (SWNS), has depended on the resilience of ocean ecosystems and resource-based economic activities for centuries. But while many coastal fisheries have

The coastal fishing community of Barrington, Southwest Nova Scotia (SWNS), has depended on the resilience of ocean ecosystems and resource-based economic activities for centuries. But while many coastal fisheries have developed unique ways to govern their resources, global environmental and economic change presents new challenges. In this study, I examine the multi-species fishery of Barrington. My objective was to understand what makes the fishery and its governance system robust to economic and ecological change, what makes fishing households vulnerable, and how household vulnerability and system level robustness interact. I addressed these these questions by focusing on action arenas, their contexts, interactions and outcomes. I used a combination of case comparisons, ethnography, surveys, quantitative and qualitative analysis to understand what influences action arenas in Barrington, Southwest Nova Scotia (SWNS). I found that robustness of the fishery at the system level depended on the strength of feedback between the operational level, where resource users interact with the resource, and the collective-choice level, where agents develop rules to influence fishing behavior. Weak feedback in Barrington has precipitated governance mismatches. At the household level, accounts from harvesters, buyers and experts suggested that decision-making arenas lacked procedural justice. Households preferred individual strategies to acquire access to and exploit fisheries resources. But the transferability of quota and licenses has created divisions between haves and have-nots. Those who have lost their traditional access to other species, such as cod, halibut, and haddock, have become highly dependent on lobster. Based on regressions and multi-criteria decision analysis, I found that new entrants in the lobster fishery needed to maintain high effort and catches to service their debts. But harvesters who did not enter the race for higher catches were most sensitive to low demand and low prices for lobster. This study demonstrates the importance of combining multiple methods and theoretical approaches to avoid tunnel vision in fisheries policy.

Contributors

Agent

Created

Date Created
  • 2014

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Fisheries in the news: how the media sets the agenda for seafood sustainability in the United States

Description

The media is a powerful force in shaping public discussions about marine issues. Many people lack first-hand experiences and direct sources of information about fisheries topics, so they rely heavily

The media is a powerful force in shaping public discussions about marine issues. Many people lack first-hand experiences and direct sources of information about fisheries topics, so they rely heavily on the information presented to them in the news. Thus, the media has the potential to influence public agendas based on their selective coverage of topics, which primes people to take certain information into account when making decisions. This study examines the contents of 412 newspaper articles from five national newspapers to determine which topics are receiving the most coverage and how they are being communicated to the public. The analysis considers fisheries and seafood discussions overall, as well as focusing on the three most commonly consumed seafood items in the United States: salmon, shrimp, and tuna. Systematic coding of newspaper articles shows that economic and social fisheries concerns are emphasized more than environmental concerns. Additionally, fisheries articles tend to be emphasize the importance of fishermen’s livelihoods, the dangers of international seafood trade, the economic utility of fish, and a consumer’s right to make informed decisions about seafood. Overall, there are a number of conflicts and weaknesses in the media’s coverage of fisheries, which would likely make it challenging for Americans to make informed, sustainability-minded decisions about seafood purchases and fisheries policies.

Contributors

Agent

Created

Date Created
  • 2016