Global ETD Search

1	Perceptions in the South Australian commercial fishing industry with regard to seals Gibbs, Susan Elizabeth. January 2002 (has links) (PDF) Bibliography: leaves 102-106. "The study investigates South Australian (SA) commercial fisheries and aquaculture operations and seal interactions by exploring perceptions in the commercial fishing industry and comparing them to 2nd Century fishers experiences. The results confirm that SA commercial fishers do interact with seals and that interactins with Australian Sea Lions may be disproportionately more than with New Zealand Fur Seals. While some commercial fishers experience is similar to 2nd Century fishers and consider interference by seals to be major hindrance and suggest culling for management of seals, in general, SA commercial fishers are open to mitigation initiatives including gear modifications, to address seal interactions. The dissertation also examines some management mitigation options to minimizing fisheries-seal interactions and offers recommendations." -- ABSTRACT Fisheries South Australia Fishing South Australia
2	The fisheries biology and population dynamics of snapper Pagrus auratus in northern Spencer Gulf, South Australia / David McGlennon. McGlennon, David January 2003 (has links) "December 2003" / Includes bibliographical references (leaves 203-219) / xviii, 219 leaves : ill. (some col.), maps, plates ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Environmental Biology, 2004 Lutjanidae South Australia Spencer Gulf. Fisheries South Australia Spencer Gulf.
3	Population demographics of New Zealand fur seals (Arctocephalus forsteri) McKenzie, Jane, janemckenzie@malpage.com January 2006 (has links) Assessment of trophic interactions between increasing populations of New Zealand fur seals (Arctocephalus forsteri) and fisheries in southern Australia is limited due to a lack of species specific demographic data and an understanding of the factors influencing population growth. To establish species specific demographic parameters a cross-sectional sample of New Zealand fur seal females (330) and males (100) were caught and individually-marked on Kangaroo Island, South Australia between 2000 and 2003. The seals were aged through examination of a postcanine tooth, which was removed from each animal to investigate age-specific life-history parameters. Annual formation of cementum layers was confirmed and accuracy in age estimation was determined by examination of teeth removed from individuals of known-age. Indirect methods of assessing reproductive maturity based on mammary teat characteristics indicated that females first gave birth between 4-8 years of age, with an average age at reproductive maturity of 5 years. Among reproductively mature females, age-specific reproductive rates increased rapidly between 4-7 years of age, reaching maximum rates of 70-81% between 8-13 years, and gradually decreased in older females. No females older than 22 years were recorded to pup. Age of first territory tenure in males ranged from 8-10 years. The oldest female and male were 25 and 19 years old, respectively. Post-weaning growth in females was monophasic, characterised by high growth rates in length and mass during the juvenile growth stage, followed by a gradual decline in growth rates after reproductive maturity. In contrast, growth in males was biphasic and displayed a secondary growth spurt in both length and mass, which coincided with sexual and social maturation, followed by a rapid decline in growth rates. Age-specific survival rates were high (0.823-0.953) among prime-age females (8-13 yrs of age) and declined in older females. Relative change in annual pup production was strongly correlated with reproductive rates of prime-age females and adult female survival between breeding seasons. New Zealand fur seal Kangaroo Island - South Australia New Zealand fur seal - Breeding Marine mammal populations Pinniped otarid remote chemical immobilization darting anaesthesia isoflurane midazolam zoletil tiletamine-zolazepam restraint behavioral response fecundity pregnancy rates progesterone reproduction reproductive failure site fidelity mortality territorial size dimorphism life table ageing growth layer groups re-colonization

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