Cowan, D.F. (1999) Method for assessing relative abundance, size-distribution, and growth of recently settled and early juvenile lobsters (Homarus americanus) in the lower intertidal zone. Journal of Crustacean Biology, 19(4):738-751.
Solow, A.R., A. Beet, and D.F. Cowan (2000) Optimal seasonal sampling for estimating an interannual trend. Israeli Journal of Zoology, 46:351-354.
Cowan, D.F., A.R. Solow, and A. Beet (2001) Patterns in abundance and growth of juvenile lobster, Homarus americanus. Marine and Freshwater Research, 52:1095-1102.
Ellis, S.L. and D.F. Cowan (2001) Volunteer-based monitoring of intertidal nursery grounds of American lobster, Homarus americanus. Marine and Freshwater Research, 52:1103-1112.
Cowan, D.F. (2002) Unsettling ideas on settling: juvenile lobsters in the intertidal zone. In: Proceedings of the International Lobster Workshop, Galway, Ireland.
Cowan, D.F. (2003) Identifying lobster using passive integrated transponder (PIT) tags.
Maine IS Technology, Vol VI, Issue 6.
Cowan, D.F. (2003) Using coded wire tags for mark/recapture investigations of juvenile lobster. Maine IS Technology, Vol VI, Issue 7.
Cowan, D.F. (2003) Mapping the movements of egg-bearing female lobsters and bottom temperatures. In: Prototype Biophysical Maps of the Gulf of Maine. E. Richert and Lewis Incze eds., Island Institute pp. 26-28.
Cowan, D.F., W.H. Watson, A.R. Solow, A. Mountcastle and L. Archambault (2005) Lobster movements and vulnerability to environmental stressors. In: Tlusty et al, eds. State of Lobster Science: Lobster shell disease workshop. Univ. of Mass., Boston.
Cowan featured in: Holden, C. and L. Blackburn (2006) Tag team: in the deep blue ocean. Science 313(5788):780-781.
Cowan, D.F. (2006) Robbing the lobster cradle. The New York Times. Op Ed, March 5.
Cowan, D.F., W.H. Watson, A.R. Solow, and A. Mountcastle (2007) Thermal histories of brooding lobsters, Homarus americanus, in the Gulf of Maine. Marine Biology 150:463-470.
Hodgins-Davis, A., S. Roberts, D.F. Cowan, J. Atema, C. Avolio, J. Defaveri, and G. Gerlach (2007) Characterization of SSRs from the American lobster, Homarus americanus. Molecular Ecology Notes 7:330-332.
Cowan, D.F., S.L. Ellis, and J. Roundy (2008) Field Handbook: Juvenile Lobster Monitoring Program. The Lobster Conservancy. 51 pp.
Cowan, D.F. (2010) Lobsters on the move. The Lobster Newsletter 23(1):14-17.
Cowan, D.F. (2010) Juvenile lobster census: the first 17 years. Maine Lobstermen’s Association Newsletter Feb:7.
Cowan, D.F. (2010) Why the spring fishery falls short. Commercial Fisheries News May:15B.
Cowan, D.F. (2011) Gastroliths: the secret to a successful shed. Commercial Fisheries News Mar:40
Cowan, D.F. (2011) Sleepless over lobster: can our luck hold out? Bangor Daily News, Op Ed December 1
Solow, AR and DF Cowan (2012) A test for space limitation with an application to recently settled lobsters. Marine Biology 159:467-470
McMahan, M.D., D.F. Cowan, G.D. Sherwood, J.H. Grabowski, Y.Chen (2012) Evaluation of coded microwire tag retention in juvenile American lobsters, Homarus americanus. Journal of Crustacean Biology 32(2):497-502
Cowan, D.F. (2012) Maine voices: lobster stocks will plummet if safeguards aren’t put in place soon. Portland Press Herald June 25.
Cowan, D.F. (2012) Small lobster molting frequency role in early shed. Commercial Fisheries News Oct:26
Reeder, R.J., Y. Tang, M.P. Schmidt, L.M. Kubista, D.F. Cowan, and B.L. Phillips (2013) Characterization of Structure in Biogenic Amorphous Calcium Carbonate: Pair Distribution Function and Nuclear Magnetic Resonance Studies of Lobster Gastrolith. Crystal Growth & Design 13:1905-1914
McMahan, M.D., D. Brady, D.F. Cowan, G.D. Sherwood, J.H. Grabowski (2013) Using acoustic telemetry to observe the effects of a groundfish predator (Atlantic cod, Gadus morhua) on movement of the American lobster (Homarus americanus). Canadian Journal of Fisheries and Aquatic Sciences 70:1625-1634
Cowan, D.F. (2013) Lobster limits show short-term thinking The New York Times, Room for Debate,
McMahan, M.D., D.F Cowan, Y. Chen, Grabowski, J.H., G.D. Sherwood, (submitted) Growth of juvenile lobster, Homarus americanus, in a changing environment. ICES Journal of Marine Science
For older archived publications go to www.lobsters.org
The Lobster Conservancy - Community
Volunteers, lobster fishermen, and scientists at The Lobster Conservancy work together to demystify lobster life from egg to plate. A brief explanation of the lobster life cycle (below) will help you better understand our work. For more information and reports about our volunteer programs visit www.lobsters.org.
Life Cycle of the American Lobster (Homarus americanus)
To begin life, thousands of fertilized, bead-sized, pine green eggs (about 1 mm in diameter) are pushed through openings (oviducts) at the base of the female lobster’s third pair of walking legs. Fertilized eggs travel along the underside of their mother’s abdomen until reaching the long hairs on her swimmerets (pleopods) where they remain attached for the next nine to twelve months. Inside of the egg, embryos grow by shedding their inelastic shell (exoskeleton) in a process called molting. After molting approximately 35 times within the egg, fully developed embryos hatch as pre-larvae that cling to their mother’s pleopods. Pre-larvae remain attached to the female until she releases them by fanning her pleopods in rhythmic waves. On their way toward the surface waters, they molt into a first stage larva.
Lobsters have three distinct, planktonic larval stages, all of which are found at the water’s surface during daylight hours and bright moonlight. The term plankton comes from the Greek word planktos meaning “to drift” or “to wander”. Larval lobsters are not particularly capable swimmers so their movements are largely controlled by wind and water currents. Metamorphosis from the larval to a postlarval stage occurs at the fourth molt. Postlarvae are strong swimmers and it is currently thought that they make excursions to the sea bottom, or benthos (from the Greek, meaning “depth of the sea”), sampling the substrate to find a suitable settlement site. From settlement onward lobster remain benthic (bottom dwelling).
The lower intertidal zone represents one of many habitats where postlarvae settle. Scientists have also found recently settled lobsters in shallow subtidal areas. Settling postlarvae find holes under rocks, dig tunnels in eelgrass beds, burrow in peat reefs, or find other dark shelters where they remain hidden for the first year of their lives. As they grow larger, juveniles are found outside of shelters more often and begin to explore and forage away from their burrows. The habits of a typical adolescent (large but not sexually mature) lobster are quite similar to those of an adult. Adulthood is reached after six to eight years, depending largely on the water temperature where they have grown up.
Mating is seasonal as it is centered around the peak molting period for females. Although mating has never been witnessed in the wild, laboratory observations reveal that adult males and females form a brief pair bond before mating. The female lobster molts in the shelter of a hard-shelled male, mates with him, and remains with him a few days while initially recovering from molting (the act of shedding its shell). During mating, the male transfers a spermatophore (filled with sperm and nutrients to keep the sperm alive) into the female’s seminal receptacle. Then, the female moves out to live on her own and has a voracious appetite for the next few months while she grows into her new shell. Once her shell finishes hardening, the female lobster extrudes and broods the fertilized eggs, and the cycle is repeated.
(For further details on the life cycle of lobsters see www.lobsters.org.)
The Lobster Conservancy - Education
The Lobster Conservancy Educating the Next Generation of Marine Environmental Stewards
For more information, please visit http://www.lobsters.org/education/educa.html