Matching Items (6)
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- All Subjects: Conservation Biology
- Creators: Polidoro, Beth
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 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.
ContributorsNoziglia, Andrea (Author) / Gerber, Leah (Thesis advisor) / Abbott, Joshua (Committee member) / Polidoro, Beth (Committee member) / Arizona State University (Publisher)
Created2015
Description
The Gulf of Mexico (or “Gulf”) is of critical significance to the oil and gas industries’ offshore production, but the potential for accidental petrochemical influx into the Gulf due to such processes is high; two of the largest marine oil spills in history, Pemex's Ixtoc I spill (1979) and British Petroleum's (BP) Deepwater Horizon (2010), have occurred in the region. However, the Gulf is also of critical significance to thousands of unique species, many of which may be irreparably harmed by accidental petrochemical exposure. To better manage the conservation and recovery of marine species in the Gulf ecosystem, a Petrochemical Vulnerability Index was developed to determine the potential impact of a petrochemical influx on Gulf marine fishes, therein providing an objective framework with which to determine the best immediate and long term management strategies for resource managers and decision-makers. The resulting Petrochemical Vulnerability Index (PVI) was developed and applied to all bony fishes and shark/ray species in the Gulf of Mexico (1,670 spp), based on a theoretical petrochemical vulnerability framework developed by peer review. The PVI for fishes embodies three key facets of species vulnerability: likelihood of exposure, individual sensitivity, and population resilience, and comprised of 11 total metrics (Distribution, Longevity, Mobility, Habitat, Pre-Adult Stage Length, Pre-Adult Exposure; Increased Adult Sensitivity Due to UV Light, Increased Pre-Adult Sensitivity Due to UV Light; and Abundance, Reproductive Turnover Rate, Diet/Habitat Specialization). The resulting PVI can be used to guide attention to the species potentially most in need of immediate attention in the event of an oil spill or other petrochemical influx, as well as those species that may require intensive long-term recovery. The scored relative vulnerability rankings can also provide information on species that ought to be the focus of future toxicological research, by indicating which species lack toxicological data, and may potentially experience significant impacts.
ContributorsWoodyard, Megan (Author) / Polidoro, Beth (Thesis advisor) / Saul, Steven (Thesis advisor) / Matson, Cole (Committee member) / Arizona State University (Publisher)
Created2020
Description
Plastic pollution poses a threat to the health and well-being of marine mammals across the globe. This paper takes a previously developed trait-based risk assessment framework and applies it to all 118 species of marine mammals worldwide, to help create a relative ranking of vulnerability of species to plastic ingestion and entanglement. After extensive data collection on 13 traits related to each species’ relative likelihood of exposure to plastics, species sensitivity to plastic ingestion and entanglement, and overall population resiliency, the initial trait framework was adapted and scored to calculate the relative vulnerability of marine mammals to marine microplastic pollution. Results indicate that the Hawaiian Monk Seal has one of the highest relative vulnerabilities to macroplastic pollution among all marine mammals. Furthermore, this exercise highlighted several areas where future research is needed, including expanding the framework to microplastics, applying the framework to coastal human populations, and further investigation of unknown life history traits of various marine mammals.
ContributorsFredette-Roman, Cassidy (Author) / Polidoro, Beth (Thesis advisor) / Rolsky, Charles (Committee member) / Minteer, Ben (Committee member) / Arizona State University (Publisher)
Created2022
Description
Marine plastic pollution (MPP) has emerged as one of the most pressing global environmental challenges of the anthropocene. There has been an upsurge in investment to mitigate MPP; however, interventions can be costly, inequitable, and ineffective in achieving their objectives. In my dissertation, I aim to research key considerations for creating cost-effective, equitable mitigation strategies for MPP and its impacts to marine biodiversity and coastal communities. In chapter one, I introduce the challenges plastic pollution poses. In chapter two, I use seascape ecology theory to present the concept of the plastic-scape and describe how seascape ecology principles, methods, and approaches to transdisciplinary science can inform research to mitigate MPP. In chapter three, I present a framework to help decision makers estimate the total cost of MPP interventions and partial costs accrued by stakeholder groups. I then apply this framework to two quantitative case studies and four comparative case studies to exemplify its use and highlight the ways spatial scale, temporal scale, and socio-economic conditions influence the intervention cost and cost distribution. In chapter four, I employ a trait-based approach to produce a framework for developing indices of species vulnerability to macroplastic pollution. Finally, in chapter five, I implement the framework developed in the previous chapter and present a multi-taxonomic, macroplastic vulnerability index for three marine taxa—mammals, birds, and turtles—to identify the marine species most vulnerable to macroplastic pollution in Hawai‘i. Overall, my dissertation shows how policy-driven, systemic research of MPP and its interventions can improve efforts to address MPP and its socio-economic and ecological consequences.
ContributorsMurphy, Erin (Author) / Gerber, Leah R (Thesis advisor) / Polidoro, Beth (Thesis advisor) / Rochman, Chelsea (Committee member) / Dooley, Kevin (Committee member) / Arizona State University (Publisher)
Created2023
Description
Cetacean-based ecotourism is a popular activity and an important source of revenue for many countries. Whale watching, a subset of cetacean-based ecotourism, is vital to supporting conservation efforts and provides numerous benefits to local communities including educational opportunities and job creation. However, the sustainability of whale-based ecotourism depends on the behavior and health of whale populations and is therefore vital that ecotourism industries consider the impact their activities have on whale reproductive behavior. To address this statement, behavioral data (e.g. direction change, breaching, slap behaviors, diving, and spy hops) were collected from humpback whales (Megaptera novaeangliae) in Las Perlas Archipelago off the Pacific coast of Panama to determine if vessel presence had an influence on whale behaviors. Studies were recorded during their breeding season from August through September in 2019. Based on 47 behavioral observations, higher boat density corresponded with humpback whales changing direction which is believed to be a sign of disturbance. This result is important given Panamanian regulations implemented on February 13 of 2007 prohibit whale-based tourism from disturbing whales, which is measured as changes in behavior. Because there is no systematic monitoring of whale watching activity to enforce the regulations, there is currently little compliance among tour operators. The integration of animal behavior research into management planning will result in more effective regulation and compliance of conservation policies.
ContributorsAmrein, Arielle (Author) / Gerber, Leah R. (Thesis advisor) / Guzman, Hector M (Committee member) / Polidoro, Beth (Committee member) / Arizona State University (Publisher)
Created2020
Description
Marine ecosystems are currently being impacted by various threats; however, quantification of the impacts of known threats and the population status of species are often conducted at different scales, depending upon stakeholder needs. Global-scale species assessments can mask the impact of local or regional threats within the context of global conservation priorities even as conservation policies are generally implemented at the local or regional scale. This work aims to identify the regional threats currently impacting species present within the Gulf of Mexico as well as the current polices addressing those threats. Species currently impacted by threats were used to build an ecosystem model to estimate food web dynamics in the Gulf of Mexico. This model is the first of its kind to incorporate data from more than 1500 species occurring in the Gulf including all marine bony shorefishes, marine reptiles, complete clades of select marine invertebrates, marine birds, marine mammals, and chondrichthyans. Comprehensive analyses of these groups are important for an improved understanding of the functioning of the Gulf of Mexico food web and the impact of identified threats on food web dynamics. The identification of current threats and food web dynamics will help to inform conservation policy moving forward. Properly framed conservation efforts are more likely to be widely accepted and successful when there is an improved understanding on how policies can impact stakeholders both economically and through changing practices. Finally, an investigation of the legal frameworks currently recognized in the Gulf of Mexico was done to build an example tri-national framework between the United States, Mexico, and Cuba focusing on current conservation gaps allowing for specific regional conservation concerns to be addressed.
ContributorsStrongin, Kyle (Author) / Polidoro, Beth (Thesis advisor) / Saul, Steven (Committee member) / Gerber, Leah (Committee member) / Arizona State University (Publisher)
Created2021