Demographic Evidence of Illegal Harvesting of an Endangered Asian Turtle

Yik Hei SUNG*, Nancy E. KARRAKER, Billy C.H. HAU

*Corresponding author for this work

Research output: Journal PublicationsJournal Article (refereed)

20 Citations (Scopus)

Abstract

Harvesting pressure on Asian freshwater turtles is severe, and dramatic population declines of these turtles are being driven by unsustainable collection for food markets, pet trade, and traditional Chinese medicine. Populations of big-headed turtle (Platysternon megacephalum) have declined substantially across its distribution, particularly in China, because of overcollection. To understand the effects of chronic harvesting pressure on big-headed turtle populations, we examined the effects of illegal harvesting on the demography of populations in Hong Kong, where some populations still exist. We used mark-recapture methods to compare demographic characteristics between sites with harvesting histories and one site in a fully protected area. Sites with a history of illegal turtle harvesting were characterized by the absence of large adults and skewed ratios of juveniles to adults, which may have negative implications for the long-term viability of populations. These sites also had lower densities of adults and smaller adult body sizes than the protected site. Given that populations throughout most of the species' range are heavily harvested and individuals are increasingly difficult to find in mainland China, the illegal collection of turtles from populations in Hong Kong may increase over time. Long-term monitoring of populations is essential to track effects of illegal collection, and increased patrolling is needed to help control illegal harvesting of populations, particularly in national parks. Because few, if any, other completely protected populations remain in the region, our data on an unharvested population of big-headed turtles serve as an important reference for assessing the negative consequences of harvesting on populations of stream turtles.

Original languageEnglish
Pages (from-to)1421-1428
Number of pages8
JournalConservation Biology
Volume27
Issue number6
DOIs
Publication statusPublished - Dec 2013
Externally publishedYes

Fingerprint

turtle
turtles
demographic statistics
China
mark-recapture method
food market
population decline
history
demography
medicine
protected area
body size
viability
national park
sociodemographic characteristics
pets
long term effects
monitoring
national parks
conservation areas

Keywords

  • Big-headed turtle
  • China
  • Overcollection
  • Overexploitation
  • Platysternon megacephalum

Cite this

SUNG, Yik Hei ; KARRAKER, Nancy E. ; HAU, Billy C.H. / Demographic Evidence of Illegal Harvesting of an Endangered Asian Turtle. In: Conservation Biology. 2013 ; Vol. 27, No. 6. pp. 1421-1428.
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Demographic Evidence of Illegal Harvesting of an Endangered Asian Turtle. / SUNG, Yik Hei; KARRAKER, Nancy E.; HAU, Billy C.H.

In: Conservation Biology, Vol. 27, No. 6, 12.2013, p. 1421-1428.

Research output: Journal PublicationsJournal Article (refereed)

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