A New Abundance Estimate for the Finless Porpoise Neophocaena asiaeorientalis on the West Coast of Korea: An Indication of Population Decline
2
조회
0
다운로드
9
인용
0
참고문헌
키워드
초록
The west coast of Korea is the largest habitat for finless porpoises, with approximately 36,000 individuals reported in 2005 (Park et al., 2007). To date, there have been no subsequent finless porpoise population estimates. However, in recent bycatches, finless porpoises accounted for the highest proportion of all cetaceans and have been reported to be most frequently caught on the west coast of Korea (Kim et al., 2013). The present study, conducted in 2011, enumerated finless porpoises inhabiting the west coast of Korea using a line transect survey in offshore and inshore regions to assess variations in their abundance. In offshore regions we found the population density of finless porpoises to be 0.122 ind./km2, whereas it was 0.565 ind./km2 in 2004. In inshore regions, the population density of finless porpoises was 0.151 ind./km2, whereas it was 0.638 ind./km2 in 2005. Therefore, we estimate that the population densities of finless porpoises in both offshore and inshore regions of the west coast of Korea decreased by approximately 70% between 2004/2005 and 2011. It is imperative to mitigate the bycatch of finless porpoises and protective action is urgently needed in the near inshore regions.
Abstract
The west coast of Korea is the largest habitat for finless porpoises, with approximately 36,000 individuals reported in 2005 (Park et al., 2007). To date, there have been no subsequent finless porpoise population estimates. However, in recent bycatches, finless porpoises accounted for the highest proportion of all cetaceans and have been reported to be most frequently caught on the west coast of Korea (Kim et al., 2013). The present study, conducted in 2011, enumerated finless porpoises inhabiting the west coast of Korea using a line transect survey in offshore and inshore regions to assess variations in their abundance. In offshore regions we found the population density of finless porpoises to be 0.122 ind./km2, whereas it was 0.565 ind./km2 in 2004. In inshore regions, the population density of finless porpoises was 0.151 ind./km2, whereas it was 0.638 ind./km2 in 2005. Therefore, we estimate that the population densities of finless porpoises in both offshore and inshore regions of the west coast of Korea decreased by approximately 70% between 2004/2005 and 2011. It is imperative to mitigate the bycatch of finless porpoises and protective action is urgently needed in the near inshore regions.
참고문헌 (15)
- Akaike, H, "A Celebration of Statistics", pp.1~24 (1985), Springer-Verlag
- Buckland, ST, "Estimating Abundance of Biological Populations", pp.446~ (1999), Chapman & Hal
- Buckland, ST, "Introduction to Distance Sampling" (2001), Oxford University Press
- Jefferson, TA, "Marine Mammals of the World: A comprehensive guide to their identification" (2003), Academic
- Kasuya T, "The population of finless porpoise in the Inland Sea of Japan", Sci Rep Whales Res Inst, 31, pp.1~44 (1979)
- Kasuya, "Abundance decline in the finless porpoise population in the Inland Sea of Japan", Raffles Bull Zoo Suppl, Suppl 10, pp.57~65 (2002)
- 김두남, "한국 연안 고래류의 혼획 현황", 한국수산과학회지, 46(6), pp.892~900 (2013), 한국수산과학회
- 김현우, "직선횡단조사에 의한 서해 연안 봄철 바닷새의 분포 양상", 한국수산과학회지, 47(6), pp.973~977 (2014), 한국수산과학회[DOI]
- Miyashita T, "Density and its seasonal change of finless porpoise in the Ise", Mikawa Bay, 1994, 58~
- 박겸준, "Line Transect에서 발견율함수 추정에 사용되는 모델에 따른 상괭이, Neophocaena phocaenoides의 자원개체수 추정", 한국수산과학회지, 40(4), pp.201~209 (2007), 한국수산과학회
- Reilly SB, "Rates of increase in dolphin population size", Fish Bull, 84, pp.527~533 (1986)
- 손호선, "목시조사(2000-2010)에 의한 한국 연안 고래류의 종류 및 분포", 한국수산과학회지, 45(5), pp.486~492 (2012), 한국수산과학회
- Thomas, L, "Distance 6.0. Release “x”1", ~ (2009)
- Wang JY, "Detecting recent speciation events : the case of the finless porpoise(genus Neophocaena)", Heredity, 101, pp.145~156 (2008)
- Yoshida H, "Finless porpoise abundance in Omura Bay, Japan : Estimation from aerial sighting surveys", J Wild Manage, 39, pp.239~247 (1998)