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1	Population Genetics of St. Lawrence Beluga Whales, Assessment of Inbreeding by DNA Fingerprinting and Assessment of Biopsy Darting Factors for Minimal Wounding and Effective Sample Retrieval / Population Genetics of St. Lawrence Beluga Whales Patenaude, Nathalie J. 12 1900 (has links) The endangered St. Lawrence beluga (Delphinapterus leucas) population is not recovering from severe depletion despite its protected status over the past 20 years. DNA fingerprinting analysis of St. Lawrence beluga whales with three minisatellite probes (Jeffreys 33.6, 33.15 and Ml3) indicate a reduced level of genetic variability compared to Mackenzie Delta animals. The average band-sharing between individuals of the St. Lawrence beluga population for the three probes (0.534, 0.573, 0.478) was significantly higher than the average band-sharing of the Mackenzie Delta beluga population for the same probes (0.343, 0.424, 0.314). Higher levels of mean homozygosity in the isolated St. Lawrence belugas (0.33 vs 0.21) as well as a high degree of relatedness suggest that this population is inbred and that inbreeding depression is a factor in the lack of recovery of the St. Lawrence beluga population. Because sampling of some beluga populations may be biased, there is the need of alternative sampling procedures such as biopsy darting. To evaluate the impact of biopsy darting on beluga whales, different combinations of dart and stop sizes were tested on fresh beluga carcasses and the effect of different factors on the success of retrieval and the extent of wounding were evaluated. Tips with smaller diameters were more likely to retrieve a sample than those with larger diameters (p <0.05) and longer tips were also more likely to retrieve a sample than shorter tips (p < 0.10). The force of impact, a function of draw weight and distance, had a significant effect on the severity of wounding (p<0.05). The samples obtained from all biopsy darts tested yielded sufficient amounts of DNA for genetic analysis. / Thesis / Master of Science (MS) st. lawrence beluga whales interbreeding population genetics biopsy darting dna fingerprinting sample retrieval
2	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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Population Genetics of St. Lawrence Beluga Whales, Assessment of Inbreeding by DNA Fingerprinting and Assessment of Biopsy Darting Factors for Minimal Wounding and Effective Sample Retrieval / Population Genetics of St. Lawrence Beluga Whales

Population demographics of New Zealand fur seals (Arctocephalus forsteri)