the horseshoe crab of delaware bay
DESCRIPTION
The Horseshoe Crab of Delaware Bay. Limulus polyphemus. (Schaul 2010). Outline. Horseshoe Crab Overview Background Physical features Reproduction Nest Sites Life cycle Endangered? Why care? Important ecologically for migratory birds Production of LAL - PowerPoint PPT PresentationTRANSCRIPT
Limulus polyphemus
(Schaul 2010)
OutlineHorseshoe Crab Overview
BackgroundPhysical featuresReproduction
Nest SitesLife cycle
Endangered?Why care?
Important ecologically for migratory birdsProduction of LALBait for commercial harvesting of whelk and
eelFuture Research?
BackgroundPhylum Arthropoda
Dates from Cambrian period
Habitatshallow water along North American Atlantic
coast
Swims with abdominal platesWalks with walking legs
Feed at night – worms & small mollusks
(Chernoff 2011)
Physical Features
Ventral View
(CCCMKC 2005)
(Skytitles 2010)
Dorsal View
ReproductionNeeded:
High tideSpring/summer
seasonSexually mature
female and male(s)
Process:Female buries eggs
into sand External
fertilization
(Query 2008)
Reproduction: Who’s the Daddy?
(Brockmann et al. 1994)
Low Tide
Location, location, location!Just above mean high tide
lineSandy beachesSloped beaches
Nest Sites(ERDG 2009)
(ERDG 2009)
Nest Sites- Slope Study(Botton & Loveland 1987)
Sloped beaches vs. Flat beaches Similar beaches, except degree of slope
4,300 total stranded horseshoe crabs20-25% of stranded from sloped beach
Blinded/Partially blinded HsCSimilar data
(Penn & Brockmann 1994)(Penn & Brockmann 1994)
(Penn & Brockmann 1994)
Life Cycle(Penn & Brockman 1994)
Egg 2 to 4 weeks
Trilobite larvae 2 weeks
Juvenile up to 10 years
Adult 19 year life span average
(ERDG 2009)
(Query 2008)
Endangered?Population numbers decreasing
Natural threatsMaturation durationDangers during matingEgg/larval mortality
HarvestingBiomedical research & companiesScientific researchBait for fisheries
Why Care? Important ecologically for migratory
birds
Production of LAL
Bait for commercial harvesting of whelk and eel$ Economy $
(Karpanty et al. 2006)
(Rizzardi 2009)
(Breese 2009)
Limulus Amoebocyte Lysate (LAL)
(Blackfang 2011)
(Charles River Laboratories2011)
Further ResearchPopulation structure
Sex structure
Limited studiesConfined to
Delaware BayMost research on
spawning populations
(Volz 2008)
Literature Cited Botton, M. L. & R. E. Loveland. 1987. Orientation of the horseshoe crab, Limulus Polyphemus, on a sandy
beach. Biological Bulletin 173(2):289-298. Brockmann, H.J. 1990. Mating behavior of horseshoe crabs, Limulus polyphemus. Behaviour
114(1/4):206-220. Brockmann, H.J., T. Colson, W. Potts. 1994. Sperm competition in horseshoe crabs (Limulus
polyphemus). Behavioral Ecology and Sociobiology 35(3):153-160. Coursey, Y., N. Ahmad, B.M. McGee, N. Steimel, M. Kimble. 2003. Amebocyte production begins at stage
18 during embryogenesis in Limulus polyphemus. Biological Bulletin 204(1):21-27. DNR. 2005. Horseshoe crabs: a living fossil. Maryland Departments of Natural Resources. Available:
http://www.dnr.state.md.us/education/horseshoecrab/. (June 2011). Hickman, C.P., L.S. Roberts, S.L. Keen, A. Larson, D.J. Eisenhour. 2007. Animal diversity, 4th Edition.
McGraw Hill, Boston. Karpanty, S. M., J.D. Fraser, J. Berkson, L. J. Niles, A. Dey, E.P. Smith. 2006. Horseshoe crab eggs
determine red knot distribution in Delaware Bay. The Journal of Wildlife Management 70(6):1704-1710. Penn, D. & H.J. Brockmann. 1994. Nest-site selection in the horseshoe crab, Limulus polyphemus.
Biological Bulletin 187(3):373-384. Rizzardi, K. 2009. With red knots on the candidate list, third circuit declares emergency listing dispute
moot. ESA BLAWG. Available: http://www.esablawg.com/esalaw/ESBlawg.nsf/d6plinks/KRII-7QA2EU. (June 2011).
Rutecki, D., R.H. Carmichael, I. Valiela. 2004. Magnitude of harvest of Atlantic horseshoe crabs, Limulus polyphemus, in Pleasant Bay, Massachusetts. Estuaries 27(2):179-187.
Sekiguchi, K., H. Seshimo, H. Sugita. 1988. Post-embryonic development of the horseshoe crab. Biological Bulletin 174(3):337-345
Smith, D.R., P.S. Pooler, R.E. Loveland, M.L. Botton, S.F. Michels, R.G. Weber, D.B. Carter. 2002. Horseshoe crab (Limulus polyphemus) reproductive activity on Delaware Bay beaches: interactions with beach characteristics.
Graphics Cited Blackfang. 2011. Horseshoe Crab blood = $15,000. NG BBS. Available:
http://www.newgrounds.com/bbs/topic/1251364/1. (June 2011). Breese, G. 2009. Red Knot feeding on eggs of Horseshoe crabs. Wikipedia.
Available: http://en.wikipedia.org/wiki/File:Red_knot_horseshoe_crab_feeding.jpg. (June 2011).
CCCMKC. 2005. Horseshoe crab menu. Available: http://cccmkc.edu.hk/~kei-kph/Fossil/Horseshoe%20crab%20menu.htm. (June 2011).
Charles River Laboratories. 2011. Horseshoe crab (Limulus polyphemus) facts and figures. Available: http://info.criver.com/endotoxin_and_rapid_microbiological_products/horseshoecrab1.html. (June 2011).
Chernoff, D. 2011. Shoreline. Available: http://www.dcwild.com/index.htm. (May 2011).
ERDG. 2009. The Horseshoe Crab. Ecological Research & Developmental Group. Available: http://www.horseshoecrab.org/nh/life.html. (May 2011)
Greer, S. 2007. Horseshoe crabs. Smithsonian National Museum of Natural History. Available: http://www.mnh.si.edu/exhibits/natures_best_2006/gallery/horseshoecrabs.html. (June 2011).
Photos Cited Rizzardi, K. 2009. With red knots on the candidate list, third circuit
declares emergency listing dispute moot. ESA BLAWG. Available: http://www.esablawg.com/esalaw/ESBlawg.nsf/d6plinks/KRII-7QA2EU. (June 2011).
Schaul, J. 2010. Horseshoe crabs need compassion and help to survive. National Geographic News Watch. Available: http://newswatch.nationalgeographic.com/2010/11/04/horshoe_crabs_need_compassion/. (May 2011).
Skytitles. 2010. What types of hermit crabs should be placed in a saltwater aquariums? Zimbio. Available: http://www.zimbio.com/Pets+and+More+Pets/articles/r3J16YIXqzR/Types+Hermit+Crabs+Placed+Saltwater+Aquariums. (June 2011)
Query, S. 2008. Crash: a tale of two species. Audobon. Available: http://www.audubonmagazine.org/webexclusives/twospecies-webExclusives.html. (June 2011)
Volz, M. 2008. Limulus polyphemus: Atlantic Horseshoe Crab-Habitat. UWLax Organismal Biology. Available: http://bioweb.uwlax.edu/bio203/2011/volz_mack/contact.htm. (June 2011).
(Greer 2007)