Fecal DNA typing to determine the structure of Eurasian otter (Lutra lutra) populations along two stream systems in Kinmen

Autor: Chih-Ming Hung, 洪志銘
Rok vydání: 2003
Druh dokumentu: 學位論文 ; thesis
Popis: 91
Noninvasive molecular methods were used to obtain data on the population structure and spatial organization of Eurasian otters (Lutra lutra) in Kinmen. DNA samples were extracted from fresh spraints collected in Kinmen every season from February to November 2001 and genotyped for a panel of 7 microsatellites and SRY gene to identify individual genotypes and sex. 222 (65%) of 343 spraints were successfully genotyped for the panel and 38 different genotypes (19 females and 19 males) were identified. The probability of false homozygotes came from allelic dropout was < 0.005 and the microsatellite panel with the probability of identity of < 0.01, even for siblings, was powerful enough to estimate the population size. 13 (34%) of 38 genotypes were residents (the individuals that were identified for more than one season), and each of the two streams accommodated six and seven residents respectively. The other 25 genotypes were floaters (the individuals that were only identified in one season). The density of 1.5-1.8 otters/km, or 0.8-1.1 otters/km for residents, was higher than that estimated in other studies. The mean active ranges of female and male residents were about 1.3 km and 2.3 km respectively. Female residents lived in exclusive group ranges, and each range was occupied by two to three females. According to the data of genetics and spraints distribution, females within the same group ranges were likely to be a family in one stream, but were less related in the other stream. The ranges of male residents overlapped with no more than one group range of female residents. Most of these otters, including residents and floaters, appeared in the same range tend to be more related to each other. There were relative more floaters identified along the stream with a more complex waterway system. The complexity of the waterways may help provide a good network of paths for floaters.
Databáze: Networked Digital Library of Theses & Dissertations