scholarly journals Abundance and Trends of Indo-Pacific Finless Porpoises (Neophocaena phocaenoides) in Hong Kong Waters, 1996–2019

2020 ◽  
Vol 7 ◽  
Author(s):  
Thomas A. Jefferson ◽  
Jeffrey E. Moore
Keyword(s):  
Hong Kong ◽  
Population Biology ◽  
Process Model ◽  
Dry Season ◽  
Process Time ◽  
Medium Size ◽  
Line Transect ◽  
Finless Porpoise ◽  
Cumulative Impact ◽  
Neophocaena Phocaenoides

The Indo-Pacific finless porpoise (Neophocaena phocaenoides) occurs year-round in waters of southern and eastern Hong Kong. The population biology of the population was studied in the late 1990s and early 2000s, but has not been examined recently. There are several threats facing the animals, and there has been recent concern about this species’ status, due to an increase in the number of strandings in Hong Kong. Line-transect surveys using medium-size vessels have been conducted for small cetaceans in most of Hong Kong’s waters since 1996. We examined the density and abundance of finless porpoises in this area, using a Bayesian hierarchical framework, consisting of a Markov process model used to describe population dynamics and a distance-sampling observation model that links the line-transect data to the latent biological process. Time-series analyses for both dry- and wet-season data from 1996 to 2019 showed annual fluctuations in abundance indices, but no evidence of a significant long-term trend in finless porpoise abundance in Hong Kong. This indicates that the increase in strandings may be related to some factor other than changing population size of Hong Kong finless porpoises. In 2019, there were approximately 176 finless porpoises in Hong Kong’s waters in the dry season (winter/spring), the season of highest use. Highest densities (0.535 porpoises/km2) were recorded in South Lantau in the dry season. Based on the results of the current study, we recommend further survey work, improvements in data collection, possible tagging and molecular work to elucidate population structure, cumulative impact assessment, and the establishment of several marine parks for the conservation of finless porpoises in Hong Kong.

Postmortem findings in a finless porpoise (Neophocaena phocaenoides) calf stranded in Hong Kong

1999 ◽  
Vol 144 (3) ◽  
pp. 75-75 ◽  
Author(s):  
E. C. M. Parsons ◽  
G. D. Bossart ◽  
R. E. Kinoshita
Keyword(s):  
Hong Kong ◽  
Finless Porpoise ◽  
Neophocaena Phocaenoides

Strandings of Small Cetaceans in Hong Kong Territorial Waters

1998 ◽  
Vol 78 (3) ◽  
pp. 1039-1042 ◽  
Author(s):  
E.C.M. Parsons
Keyword(s):  
Hong Kong ◽  
Summer Monsoon ◽  
Human Disturbance ◽  
Monsoon Season ◽  
Anthropogenic Pollution ◽  
Finless Porpoise ◽  
Summer Monsoon Season ◽  
Neophocaena Phocaenoides ◽  
Sousa Chinensis ◽  
Official Records

Since official records were first initiated in 1973, there have been reports of 154 small cetacean strandings in Hong Kong territorial waters. The species Neophocaena phocaenoides (finless porpoise) and Sousa chinensis (Indo-Pacific hump-backed dolphin) accounted for 77% of these strandings. There are seasonal peaks in the number of reported strandings: Sousa chinensis is more frequently reported during the summer monsoon season and Neophocaena phocaenoides is more frequent in the winter. Almost a third of all finless porpoises stranded were calves. The number of reported small cetacean strandings in Hong Kong has increased dramatically in recent years; partially due to an increasing awareness of local cetaceans and possibly due to escalating levels of human disturbance and anthropogenic pollution.

Detection of Brucella ceti in Two Indo-Pacific Finless Porpoises (Neophocaena Phocaenoides) Stranded in Hong Kong

2020 ◽  
Vol 56 (3) ◽  
pp. 698
Author(s):  
Nathalie F. Mauroo ◽  
Rosana W. S. Poon ◽  
Philip S. L. Beh ◽  
Patrick C. Y. Woo
Keyword(s):  
Hong Kong ◽  
Neophocaena Phocaenoides

Diversity, distribution and relative abundance of avifauna at Ansas Dam and surrounding farmland site Debre Berhan Town, Ethiopia

2020 ◽  
pp. 175815592096320
Author(s):  
Alemayehu Shiferaw ◽  
Dereje Yazezew
Keyword(s):  
Relative Abundance ◽  
Bird Species ◽  
Dry Season ◽  
Avian Species ◽  
Ordinal Scale ◽  
Line Transect ◽  
Wet Season ◽  
Debre Berhan ◽  
Dry Seasons ◽  
Wet And Dry Seasons

The diversity, distribution, and relative abundance of avifauna were studied at and Around Ansas Dam, Debre Berhan Town, Ethiopia, from early September 2018 to early February 2019, covering both wet and dry seasons. Line transect technique was employed to study the diversity, abundance and distribution of birds species in the farmland site while total count employed on the dam. Data were collected in both wet and dry seasons from 6:30 to10:00 early morning and 15:30 to 18.00 late afternoon, when birds are more active. The data were analyzed with Shannon-Weiner Index, Simpson Index, Evenness Index, and relative abundance. A total of 45 bird species (35 in the dam and 22 in the farmland) belonging to nine orders and 21 families were recorded during the study period. Order Passeriformes (37.8%) followed by order Charadriformes (24.4%) were represented highest number. From all identified species at Ansas Dam and surrounding farmland, Abyssinian longclaw, Black-headed siskins, White-tailed swallow, Blue-winged goose, and Spot-breasted lapwing were endemic birds to Ethiopia. The highest Shannon diversity (H′ = 2.1) was recorded in dam during the dry season while the lowest (H′ = 1.78) was recorded during wet season in farmland. However, the Simpson diversity Index of avian species indicated relatively higher avian species diversity during the dry season in dam (D = 0.80) than farmland (D = 0.71) habitat. Evenness was highest in the dam (E = 0.65) and lowest in the farmland (E = 0.58) habitat. More avian species similarity (SI = 0.42) at farmland and dam habitat during the wet season but least similarity (SI = 0.2) was observed during the dry season. Most birds had scored rare in the ordinal scale while few species with abundant and uncommon ranks in both habitats and seasons. Conservation of the different charismatic bird species should be taken as an important component of wildlife management plan in the area.

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