Ecosystems Ltd.

Aberdeen, China

Ecosystems Ltd.

Aberdeen, China
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Kwok H.K.,Ecosystems Ltd
Journal of Forestry Research | Year: 2017

This paper reports observations of flocking behavior of birds in a well-protected secondary forest in Tai Po Kau Nature Reserve, Hong Kong Special Administrative Region, China. A total of 1025 flocks including 5255 birds and 48 species were observed between October 2002 and November 2003. Most flocks consisted of only one species. The observed flocks averaged 1.79 ± 0.05 (SE) species and 5.13 ± 0.18 (SE) birds. The Japanese White-eye was the most numerous species and was present in 21.6% of the observed flocks. Seasonal trends in both flock size and number of species were similar to those in overall bird density and species richness in the study area reported in a previous study. © 2017 Northeast Forestry University and Springer-Verlag Berlin Heidelberg

Xia R.,Northeast Forestry University | Huang X.,Qiqihar University | Yang S.,Northeast Forestry University | Xu Y.,Northeast Forestry University | And 3 more authors.
Journal of Forestry Research | Year: 2011

Commercial farming of anuran species that are declining in the wild raises a need to discriminate wild from farmed frogs. We hypothesized wild frogs might have extended hindlimbs due to greater frequency or intensity of jumping relative to farmed frogs, highlighting a morphometric approach to discrimination of wild from farmed frogs using hindlimb length. In the present study, Dybowski's frog (Rana dybowskii) was used to test this hypothesis. We measured body mass (Mb) and hindlimb length (Lh) of 2-year old farmed frogs and wild frogs aged 2 to 5 years. Dybowski's frog demonstrated significant dimorphism in Mb and Lh. Mb was significantly greater among farmed 2-year old frogs in both sexes (p=0.000), while only among females was Lh significantly greater for wild frogs (p=0.000). Lh/Mb was used as an index for origin discrimination to eliminate the influence of Mb due to variation of husbandry conditions among farms. Mean Lh/Mb for farmed frogs was significantly lower than for wild frogs (p=0.000) in the 2-year old age class. Discrimination correctly classified 84.4% of farmed and 96.3% of wild male frogs. Among females, 92.9% of farmed frogs and 90.1% wild frogs were correctly classified. The overall correctness of classification was 92.1% and 90.8% for males and females, respectively. However, Lh/Mb revealed variation with age, resulting in reduced discriminative power for frogs ≥3 years old. We introduced a coefficient Ce to adjust the Lh/Mb of frogs ≥3 years to the level equivalent to 2-year frogs. The adjustment achieved 89.5% for overall correctness of origin for wild males and 92.4% for wild females ≥3 years old. These results show that Lh/Mb is an effective index to discriminate wild from farmed Dybowski's frog. Since the physical demands of jumping are common among anurans, this index is also potentially applicable to other anuran species. © 2011 Northeast Forestry University and Springer-Verlag Berlin Heidelberg.

Zhang L.,Northeast Forestry University | Yang S.,Northeast Forestry University | Xu Y.,Northeast Forestry University | Dahmer T.D.,Ecosystems Ltd.
Integrative Zoology | Year: 2014

Hair and feathers are composed of keratin and are indigestible, inalimental and unpalatable for carnivores. However, carnivores often ingest hair and feathers during feeding or when grooming. We hypothesized that ingestion of hair and feathers changes species diversity and relative abundance of bacteria in the gut of carnivores. To test this hypothesis, we added disinfected poultry down feathers to the normal diet of captive Arctic foxes (Alopex lagopus). We then used fluorescently labeled terminal restriction fragments (T-RFs) to examine changes in fecal bacterial diversity and abundance. The results showed that the number of bacterial species increased significantly after feather ingestion, but that total abundance was unchanged. This demonstrated that addition of disinfected feathers to the diet stimulated increased production among less abundant bacteria, resulting in a balancing of relative abundance of different bacterial species, or that some newly-ingested microbial species would colonize the gut because a suitable microhabitat had become available. This implies that the overall production of bacterial metabolites would be made up of a greater range of substances after feather ingestion. On one hand, the host's immune response would be more diverse, increasing the capacity of the immune system to regulate gut microflora. On the other hand, the animal's physiological performance would also be affected. For wild animals, such altered physiological traits would be subjected to natural selection, and, hence, persistent geographic differences in the character of ingested feathers or fur would drive speciation. © 2013 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

Qin Y.,Colby College | Nyhus P.J.,Colby College | Larson C.L.,Colby College | Larson C.L.,Colorado State University | And 6 more authors.
Biological Conservation | Year: 2015

Human-caused biodiversity loss is a global problem, large carnivores are particularly threatened, and the tiger (Panthera tigris) is among the world's most endangered large carnivores. The South China tiger (Panthera tigris amoyensis) is the most critically endangered tiger subspecies and is considered functionally extinct in the wild. The government of China has expressed its intent to reintroduce a small population of South China tigers into a portion of their historic range as part of a larger goal to recover wild tiger populations in China. This would be the world's first major tiger reintroduction program. A free-ranging population of 15-20 tigers living in a minimum of 1000km2 of habitat was identified as a target. We assessed summer and winter habitat suitability of two critical prey species, wild boar (Sus scrofa) and Sika deer (Cervus nippon), using GIS spatial models to evaluate the potential for tiger reintroduction in one likely candidate site, the 1100km2 Hupingshan-Houhe National Nature Reserve complex in Hunan and Hubei Provinces, China. Our preliminary analysis estimates that for wild boar, potential summer and winter habitat availability is 372-714km2 and 256-690km2, respectively, whereas for Sika deer, potential summer and winter habitat availability is 443-747km2 and 257-734km2, respectively. Our model identifies potential priority areas for release and restoration of prey between 195 and 790km2 with a carrying capacity of 596-2409 wild boar and 468-1929 Sika deer. Our analysis suggests that Hupingshan-Houhe could support a small population of 2-9 tigers at a density of 1.1-1.2 tigers/100km2 following prey and habitat restorations. Thus, current habitat quality and area would fall short of the target recovery goal. We identify major challenges facing a potential tiger reintroduction project and conclude that restoring the habitat and prey base, addressing concerns of local people, and enhancing coordination across park boundaries are significant challenges to meeting the broader goals of supporting a reintroduced wild tiger population. Tiger range states have committed to doubling the world's wild tigers by 2022. The results of this study have implications for China's commitment to this goal and for the future of tiger and other large carnivore reintroduction efforts in Asia and globally. © 2014 The Authors.

Yang S.H.,Northeast Forestry University | Huang X.M.,Northeast Forestry University | Huang X.M.,Qiqihar University | Xia R.,Northeast Forestry University | And 2 more authors.
Forensic Science International | Year: 2011

Wildlife has been utilized by humans throughout history and demand continues to grow today. Farming of wildlife can supplement the supply of wild-harvested wildlife products and, in theory, can reduce pressure on free-ranging populations. However, poached wildlife products frequently enter legal markets where they are fraudulently sold as farmed wildlife products. To effectively close this illegal trade in wild-captured wildlife, there is a need to discriminate wild products from farmed products. Because of the strong market demand for wild-captured frog meat and the resulting strong downward pressure on wild populations, we undertook research to develop a method to discriminate wild from farmed Dybowski's frog (Rana dybowskii) based on femur bone density. We measured femur bone density (Df) as the ratio of bone mass to bone volume. Df of wild frogs revealed a slightly increasing linear trend with increasing age (R2=0.214 in males and R2=0.111 in females, p=0.000). Wild males and wild females of age classes from 2 to ≥5 years had similar Df values. In contrast, 2-year-old farmed frogs showed significantly higher Df values (p=0.000) among males (mean Df=0.623±0.011g/ml, n=32) than females (mean Df=0.558±0.011g/ml, n=27). For both sexes, Df of wild frogs was significantly higher than that of farmed frogs (p=0.000). Among males, 87.5% (28 of 32 individuals) of farmed frogs were correctly identified as farmed frogs and 86.3% (69 of 80 individuals) of wild frogs were correctly identified as wild frogs. These results suggest that femur bone density is one reliable tool for discriminating between wild and farmed Dybowski's frog. This study also highlights a novel strategy with explicit forensic potential to discriminate wild from captive bred wildlife species. © 2010 Elsevier Ireland Ltd.

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