Molluscan Fisheries

1. Molluscan Fisheries Heather Gosnell, Martin Davis, Natalie Minor, Ben Lawhorn, Max Rossa

2. General Facts • In 2000, the world aquaculture production of molluscs was estimated at 10.73 millions of metric tonnes • The US aquaculture industry includes about 4,800 farms with combined annual revenue of $1.5 billion. • Mollusk farms and some seaweed farms can remove excess nutrients from a watershed and thus help prevent eutrophication within the watershed.

3. Cephalopod Fisheries • Commodity and supportive services provided by cephalopods contributed as much as 55% of fishery landings (tonnes) and 70% of landed values ($USD). • North Pacific ecosystems among the highest in terms of contribution to tonnage and and net profit. • More cephalopod stocks are harvested by the Japanese than by any other nation. They also serve as an important source of protein for many Mediterranean and developing countries. About 2.5 million tons of cephalopods are harvested each year.

4. Chesapeake Bay Oysters -Crassostrea virginica • The Chesapeake is justifiably famous for its oysters. Indeed, one translation of the word Chesapeake from the Algonquian language is “Great Shellfish Bay.” • Literally billions of oysters were harvested from the Chesapeake during a single century,and most of these were removed in a forty--year period • Biologists have estimated that when the English settlers reached Virginia and Maryland in the 1600s, oysters were filtering the entire Chesapeake Bay once a week. • by the late 1900s the remaining oysters would require over one year to accomplish this same feat. • The oyster population in the Bay is less than 1% of what it once was

5. Bay Scallop: Argopecten irradians • Limit:2 gallons whole bay scallops in shell, or 1 pint of bay scallop meat per person Maximum of 10 gallons of whole bay scallops in shell, or 1/2 gallon bay scallop meat per vessel • Season:June 29 - Sept. 24 • Can be farmed either on the seafloor or off the • bottom using nets suspended from long-lines • Naturally filter out food items, such as plankton, • from the water. This filter-feeding action may • even improve local water quality.

6. Effect of Ocean Acidification of Molluscan Fisheries • Industrial activities release CO2→dissolves in oceans→increases acidity • Higher acidity decreases carbonate protection for molluscs (clams, scallops, conchs) • More energy devoted to maintaining shells and less to reproduction/growth • Decline in mollusc stocks→loss of protein→erosion of income→more vulnerable developing nations

7. References • http://onlinelibrary.wiley.com/store/10.1111/j.1467-2979.2010.00369.x/asset/j.1467-2979.2010.00369.x.pdf;jsessionid=1CEC57179DC0253E5E3DA1CE7DC87F7F.f03t04?v=1&t=hmj6q1lv&s=1de8d56e1da32e883ac698b218e264b007c93653 • https://www.pices.int/publications/presentations/PICES-2011/2011-S3/S3-0955-Hunsicker.pdf • http://myfwc.com/research/saltwater/mollusc/ • http://www.scidev.net/global/water/news/africa-s-mollusc-stocks-at-risk-from-ocean-acidification-1.html • http://www.ncrac.org/nutrition/industry.htm • http://www7.taosnet.com/platinum/data/environment/impactculture.html • https://www.stmaryscity.org/Archaeology/Oyster%20in%20Chesapeake%20History.html • http://www.chesapeakelighttackle.com/wp-content/uploads/2012/01/virignianshuckersm.jpg • http://myfwc.com/research/saltwater/mollusc/bay-scallops/season/ • http://photography.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/Photography/Images/Content/cherrystone-clams-680185-sw.jpg