A Global Ecological Signal of Extinction Risk in Marine Ray-Finned Fishes

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dc.contributor.advisorKnope, Matthew
dc.contributor.authorBak, Trevor
dc.contributor.departmentTropical Conservation Biology & Environmental Science
dc.date.accessioned2022-06-24T19:37:24Z
dc.date.available2022-06-24T19:37:24Z
dc.date.issued2022-05
dc.description.degreeM.S.
dc.identifier.urihttp://hdl.handle.net/10790/7092
dc.subjectEcology
dc.subjectExtinction Risk
dc.subjectGlobal
dc.subjectMarine Fishes
dc.subjectModern Biodiversity Crisis
dc.titleA Global Ecological Signal of Extinction Risk in Marine Ray-Finned Fishes
dc.typeThesis
dcterms.abstractThe Earth is potentially entering a sixth mass extinction event comparable to the previous “big five” mass extinctions. Many marine fish species are currently facing rapid population declines from a broad range of threat types, but their extinction risk profiles are largely under-studied in comparison to their terrestrial counterparts. Selective extinction of increasing numbers of marine fish species may result in rapid alteration of global ocean ecosystem structure and function. In this study, we compiled a data set of 9,040 species of marine ray-finned fishes (class Actinopterygii) from global databases and used phylogenetic generalized linear models to examine which ecological traits are associated with increased extinction risk, based on the International Union for the Conservation of Nature (IUCN) Red List. We also assessed which threat types are driving these species towards greater extinction risk, if threatened species face a greater average number of total threat types than non-threatened species, and possible biases in the assignment of extinction risk status by the IUCN for each ecological variable. Further, we examined whether controlling for phylogenetic non-independence alters the general conclusions drawn from our study. We found that species with larger body size, longer population doubling times, life-history strategies that involve movement into brackish and/or freshwater, and pelagic species are all at elevated extinction risk. However, we found no significant difference in extinction risk based on trophic level. Commercial harvesting threatens the greatest number of species followed by pollution, development, and then climate change. We also found that threatened species, on average, simultaneously face a significantly greater total number of threat types than non-threatened species. We did identify relatively minor biases in the assignment of extinction risk status by the IUCN Red List across all traits and we further determined that controlling for phylogenetic non-independence does not strongly affect our general conclusions. Collectively, these results point to which ecological traits place marine ray-finned fishes at higher risk of extinction and which threat types most urgently need to be addressed if we are to curtail rapid alteration of global marine ecosystems.
dcterms.extent36 pages
dcterms.languageen
dcterms.publisherUniversity of Hawaii at Hilo
dcterms.rightsAll UHH dissertations and theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission from the copyright owner.
dcterms.typeText
local.identifier.alturihttp://dissertations.umi.com/hilo.hawaii:10222

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