The archaic horseshoe crabs originated 475 million years ago. Of the four extant species, two (the Chinese horseshoe crab Tachypleus tridentatus and mangrove horseshoe crab Carcinoscorpius rotundicauda) exist in southern China. Although categorized as Data Deficient on the IUCN Red List, populations of horseshoe crabs in Asia are declining as a result of loss of spawning/nursery areas from coastal reclamation, habitat destruction and pollution, bycatch from trawling, and overexploitation for biomedical uses. A slow growth rate and long maturity make horseshoe crabs vulnerable to disturbance. In China and other Asian countries an additional threat to the Chinese horseshoe crab is over-harvesting of adults for food. Horseshoe crabs are not, however, legally protected at the national level in China (although in some provinces the Chinese horseshoe crab is listed as a provincial protected animal) and many other Asian countries.
During 7–8 June 2014 the Guangxi Mangrove Research Centre, Fauna & Flora International (FFI) China Programme, Biodiversity Research Centre Academia Sinica (Taiwan) and Mangrove Ecological Research Group of the China Ecological Society organized a workshop (Nearshore Resources and Environment of Beibu Gulf—Conservation and Wise Use of Horseshoe Crabs) in Beihai, Guangxi Province, China, with financial support from the Guangxi Mangrove Research Centre, National Geographic Air and Water Conservation Fund, and the China Exploration & Research Society. Over 40 scientists, conservationists and stakeholders from mainland China, Taiwan and Hong Kong gathered to share research findings and formulate collaborative action for the conservation of horseshoe crabs in southern China.
The workshop reviewed the current status of horseshoe crabs in China. In Taiwan and Hong Kong the number of adult horseshoe crabs is particularly low. The most abundant population of Chinese horseshoe crabs in Beibu Gulf, Guangxi Province, has decreased by > 90% and c. 10% of the adults are harvested annually. The local biomedical industry has estimated that > 80% of the harvested Chinese horseshoe crabs are consumed as food and 20% are bled to produce limulus ambeocyte lysate, which is used to detect bacterial contamination in medical devices and the manufacture of drugs. Various approaches are being adopted to conserve horseshoe crabs. The Ocean Park Conservation Foundation and City University of Hong Kong have been running a juvenile horseshoe crab rearing programme in Hong Kong since 2010, to promote the importance of horseshoe crab conservation among secondary school students and the public. Scientists and conservationists in Taiwan have been promoting an integrated conservation strategy, encompassing research, artificial breeding and field release, public education and establishment of a protected area for horseshoe crabs. In mainland China, artificial breeding and field release of juvenile horseshoe crabs have been carried out to enhance wild populations. In 2013 the FFI China Programme initiated a project to promote participatory monitoring of juvenile horseshoe crabs in Beibu Gulf and strengthen the conservation network within China, of which the workshop was part.
With support from all attendees, from 22 institutions and organizations, a regional Horseshoe Crab Conservation Consortium was born. The Consortium has a mission to (1) promote the conservation status of horseshoe crabs, (2) reduce illegal utilization and trade of horseshoe crabs and promote their sustainable use, (3) promote the establishment of protected areas for horseshoe crabs and enhance effective management and habitat restoration, (4) develop research and conservation capacity and strengthen sharing of information, and (5) raise the awareness of the government, public and other stakeholders regarding the conservation of horseshoe crabs. The Consortium set up four working groups to promote efforts for population monitoring and Red List assessment, artificial breeding and field release to enhance wild populations, public education, and wise use of horseshoe crabs for societal needs. The aims of the Consortium are intended to extend beyond China and to facilitate collaboration among scientists and conservation practitioners from other Asian countries that host horseshoe crab populations.
