Journal: BioScience
Location: Delaware Bay, USA

In the 1990s, there was a 90% decline in horseshoe crab (Limulus polyphemus) egg availability due to a 10-fold increase in harvesting for bait, resulting in a decline in body weight of their predator the red knot (Calidris canutus rufa), which congregates in the Delaware Bay every May to feed on the eggs. Between 1997 and 2007 red knots declined by 75%, and the proportion weighing more than 180g by their usual departure from the Bay (26th-28th May) decreased from 0.6-0.8 to 0.14-0.4. The horseshoe crab harvest has continued to increase despite restrictions, and red knots are not recovering.

Niles LJ, Bart J, Sitters HP, Dey AD, Clark KE, Atkinson PW, Baker AJ, Bennett KA, Kalasz KS, Clark NA, Clark J, Gillings S, Gates AS, Gonz├ílez PM, Hernandez DE, Minton CDT, Morrison RIG, Porter RR, Ross RK, and Veitch CR, 2009. “Effects of Horseshoe Crab Harvest in Delaware Bay on Red Knots: Are Harvest Restrictions Working?” BioScience 59(2):153-164.
Affiliations: Conserve Wildlife Foundation of New Jersey; USGS Forest and Rangeland Ecosystem Science Centre; International Wader Study Group Bulletin; New Jersey Division of Fish and Wildlife; British Trust for Ornithology; Royal Ontario Museum; Delaware Division of Fish and Wildlife; Fundacion Inalafquen; Richard Stockton College; Victoria Wader Studies Group; Carleton University; Canadian Wildlife Service; The Shorebird Project.


Location: GCLME, West Africa

The Guinea Current Large Marine Ecosystem (GCLME) is polluted, degraded, and has declining fish stocks, but most countries in the GCLME rely on its natural resources. Local marine fishery, offshore oil production, periwinkle* harvesting and mining have an estimated value of US$49,941.4 million, of which offshore oil production accounts for 59.79%.

*Periwinkle – Catharanthus roseus G. Don (used to make the chemotherapy drug Vinblastine Sulfate)

Chukwuonea NA, Ukwec CN, Onugud A, Ibee CA, 2009. “Valuing the Guinea current large marine ecosystem: Estimates of direct output impact of relevant marine activities” Ocean & Coastal Management, 52:(3-4) 189-196, doi:10.1016/j.ocecoaman.2008.12.008

Centre for Entrepreneurship and Development Research, University of Nigeria
Department of Agricultural Economics, University of Nigeria
United Nations Industrial Development Organization (UNIDO), Vienna
Bioresources Development and Conservation programme (BDCP), Nigeria
Interim Guinea Current Commission, Ghana