東華大學圖書館 |

Shark vulnerability to fishery interactions: Assessing ecological, physiological, and social agents of risk.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Shark vulnerability to fishery interactions: Assessing ecological, physiological, and social agents of risk./
作者:	Gallagher, Austin J.
面頁冊數:	199 p.
附註:	Source: Dissertation Abstracts International, Volume: 76-10(E), Section: B.
Contained By:	Dissertation Abstracts International76-10B(E).
標題:	Aquatic sciences. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3704903
ISBN:	9781321775815

Shark vulnerability to fishery interactions: Assessing ecological, physiological, and social agents of risk.
Gallagher, Austin J.

Shark vulnerability to fishery interactions: Assessing ecological, physiological, and social agents of risk. - 199 p.

Source: Dissertation Abstracts International, Volume: 76-10(E), Section: B.

Thesis (Ph.D.)--University of Miami, 2015.

The impacts of fisheries capture on the physiology, behavior, and survival of sharks have previously been investigated via both laboratory and field studies, and have primarily been conducted in temperate waters on species commonly encountered in pelagic commercial fisheries, or with juveniles of small species which can be easily maintained in captivity. In contrast, relatively little attention has been directed towards shark capture stress and survival research in subtropical or coastal areas which contain a higher diversity of species that can also be fished nearly year-round by both commercial and recreational industries. Furthermore, the vast majority of previous work to date has relied heavily on comparing means between species for selected parameters without investigating the gradients in fishery-related variables such as hooking duration, water temperature, and animal size on stress and survival rates. Most studies have focused on either physiology or survival rates (either at-vessel, or post-release), and have not integrated methods to study the combined effects of capture for an improved assessment of vulnerability. Moreover, previous work has not included evaluations of shark behavior when captured, nor the human dimensions component (i.e., angler perceptions of risk) of capture and release. To address these knowledge gaps, I conducted an integrated, multi-pronged dissertation to assess shark vulnerability to fisheries interactions. To evaluate which factors affected shark survival, I first examined a database on shark survival in the National Marine Fisheries Service's Pelagic Observer Program and investigated the at-vessel survival of 12 shark species captured as bycatch over 12 years in the US Atlantic pelagic longline fishery. I used regression to model survival inclusive of recorded fishery-related variables which would potentially affect catch/survival for each species. After identifying a range of species-specific survival rates, I then used an experimental approach to investigate the physiological reactions, behavioral responses and survival outcomes of six coastal shark species to fisheries interactions (the process of capture and release). I performed a series of integrated field studies, including (1) blood physiological sampling, reflex performance analysis, and biotelemetry; and (2) high-resolution analysis of behavioral responses using accelerometers attached to fishing gear. Finally, I surveyed Florida saltwater recreational anglers on their conservation attitudes and perceptions towards sharks and their vulnerability to post-release mortality resulting from capture and release. Using these data, I tested the following major hypotheses: (1-null) there would be no species-specific influences of operational, environmental, or biological variables on the at-vessel hooking survival of sharks captured as bycatch; (2) the magnitude of physiological disturbance and reflex impairment in captured sharks would be correlated with hooking duration; (3) physiological disturbance and reflex impairment would be significantly influenced by biological characteristics including shark size and species; (4) satellite telemetry reporting rates would be lowest for species exhibiting higher physiological disturbance and reflex impairment; (5) species with the lowest survival rates and highest physiological stress responses would show the greatest acceleration and fighting intensities; (6) fisher demographic and subjective knowledge variables would have no influence on their conservation ethic or perceptions of shark vulnerability to recreational fishing activities; (7) anglers would not rank the threatened status of shark species differently. Results from the longline assessment indicated that survival for seven of the 12 pelagic shark species was significantly affected by at least one operational, environmental, or biological variable, and that survival rates ranged from low (33%, night shark) to very high (97%, tiger shark). Species with the highest vulnerability rankings exhibited low survival rates, low reproductive potential, and slow attainment of maturity. Field results suggested that the physiological parameter most indicative of exhaustive exercise (i.e., lactate) was significantly correlated with hooking duration and animal size. Survival rates from empirical satellite tagging efforts significantly differed between species, ranging from ~50% in great hammerhead sharks to almost 100% in tiger sharks. Sharks with the highest stress responses (blood physiology and reflex impairment) and lowest survival rates exhibited the highest acceleration forces and rates when hooked, and these species tended to exhibit lifestyles with higher metabolic demands. Survey results suggested that fishers generally comprehended the issues of post-release mortality and sharks as a species of conservation concern, but the concept of inherent species vulnerability in capture and release interactions was less understood. For the most part, the sample of anglers also ranked the vulnerabilities of shark species similarly to those obtained empirically in other parts of this dissertation. By combining results from my field studies in Florida, a range of vulnerabilities to fisheries capture and release were evident for the six species. (Abstract shortened by UMI.).

ISBN: 9781321775815Subjects--Topical Terms:

3174300
Aquatic sciences.

Shark vulnerability to fishery interactions: Assessing ecological, physiological, and social agents of risk.
LDR:06269nmm a2200289 4500 001 2074798
005 20161020134846.5
008 170521s2015 ||||||||||||||||| ||eng d
020 $a 9781321775815
035 $a (MiAaPQ)AAI3704903
035 $a AAI3704903
040 $a MiAaPQ $c MiAaPQ
100 1 $a Gallagher, Austin J. $3 3190147
245 1 0 $a Shark vulnerability to fishery interactions: Assessing ecological, physiological, and social agents of risk.
300 $a 199 p.
500 $a Source: Dissertation Abstracts International, Volume: 76-10(E), Section: B.
500 $a Adviser: Neil Hammerschlag.
502 $a Thesis (Ph.D.)--University of Miami, 2015.
520 $a The impacts of fisheries capture on the physiology, behavior, and survival of sharks have previously been investigated via both laboratory and field studies, and have primarily been conducted in temperate waters on species commonly encountered in pelagic commercial fisheries, or with juveniles of small species which can be easily maintained in captivity. In contrast, relatively little attention has been directed towards shark capture stress and survival research in subtropical or coastal areas which contain a higher diversity of species that can also be fished nearly year-round by both commercial and recreational industries. Furthermore, the vast majority of previous work to date has relied heavily on comparing means between species for selected parameters without investigating the gradients in fishery-related variables such as hooking duration, water temperature, and animal size on stress and survival rates. Most studies have focused on either physiology or survival rates (either at-vessel, or post-release), and have not integrated methods to study the combined effects of capture for an improved assessment of vulnerability. Moreover, previous work has not included evaluations of shark behavior when captured, nor the human dimensions component (i.e., angler perceptions of risk) of capture and release. To address these knowledge gaps, I conducted an integrated, multi-pronged dissertation to assess shark vulnerability to fisheries interactions. To evaluate which factors affected shark survival, I first examined a database on shark survival in the National Marine Fisheries Service's Pelagic Observer Program and investigated the at-vessel survival of 12 shark species captured as bycatch over 12 years in the US Atlantic pelagic longline fishery. I used regression to model survival inclusive of recorded fishery-related variables which would potentially affect catch/survival for each species. After identifying a range of species-specific survival rates, I then used an experimental approach to investigate the physiological reactions, behavioral responses and survival outcomes of six coastal shark species to fisheries interactions (the process of capture and release). I performed a series of integrated field studies, including (1) blood physiological sampling, reflex performance analysis, and biotelemetry; and (2) high-resolution analysis of behavioral responses using accelerometers attached to fishing gear. Finally, I surveyed Florida saltwater recreational anglers on their conservation attitudes and perceptions towards sharks and their vulnerability to post-release mortality resulting from capture and release. Using these data, I tested the following major hypotheses: (1-null) there would be no species-specific influences of operational, environmental, or biological variables on the at-vessel hooking survival of sharks captured as bycatch; (2) the magnitude of physiological disturbance and reflex impairment in captured sharks would be correlated with hooking duration; (3) physiological disturbance and reflex impairment would be significantly influenced by biological characteristics including shark size and species; (4) satellite telemetry reporting rates would be lowest for species exhibiting higher physiological disturbance and reflex impairment; (5) species with the lowest survival rates and highest physiological stress responses would show the greatest acceleration and fighting intensities; (6) fisher demographic and subjective knowledge variables would have no influence on their conservation ethic or perceptions of shark vulnerability to recreational fishing activities; (7) anglers would not rank the threatened status of shark species differently. Results from the longline assessment indicated that survival for seven of the 12 pelagic shark species was significantly affected by at least one operational, environmental, or biological variable, and that survival rates ranged from low (33%, night shark) to very high (97%, tiger shark). Species with the highest vulnerability rankings exhibited low survival rates, low reproductive potential, and slow attainment of maturity. Field results suggested that the physiological parameter most indicative of exhaustive exercise (i.e., lactate) was significantly correlated with hooking duration and animal size. Survival rates from empirical satellite tagging efforts significantly differed between species, ranging from ~50% in great hammerhead sharks to almost 100% in tiger sharks. Sharks with the highest stress responses (blood physiology and reflex impairment) and lowest survival rates exhibited the highest acceleration forces and rates when hooked, and these species tended to exhibit lifestyles with higher metabolic demands. Survey results suggested that fishers generally comprehended the issues of post-release mortality and sharks as a species of conservation concern, but the concept of inherent species vulnerability in capture and release interactions was less understood. For the most part, the sample of anglers also ranked the vulnerabilities of shark species similarly to those obtained empirically in other parts of this dissertation. By combining results from my field studies in Florida, a range of vulnerabilities to fisheries capture and release were evident for the six species. (Abstract shortened by UMI.).
590 $a School code: 0125.
650 4 $a Aquatic sciences. $3 3174300
650 4 $a Conservation biology. $3 535736
650 4 $a Environmental science. $3 677245
690 $a 0792
690 $a 0408
690 $a 0768
710 2 $a University of Miami. $b Interdisciplinary Studies (Graduate School). $3 3190148
773 0 $t Dissertation Abstracts International $g 76-10B(E).
790 $a 0125
791 $a Ph.D.
792 $a 2015
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3704903