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Possible Demographic Consequences of Intraspecific Shelter Competition among American Lobsters

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Abstract Pioneering work by J. Stan Cobb described how habitat architecture and body size scaling affect shelter-related behavior of American lobsters. Subsequent research suggested that shelter availability and competition could set local carrying capacity and demographics for this species. To determine how shelter spacing affects population density, the intensity of intraspecific competition and the distribution of body size for this species, I deployed sets of 10 identically sized artificial shelters spaced at distances of 2.5, 0.5, 1.0, 1.5 and 2.0 meters on otherwise featureless substrate at 10 m depth in mid-coast Maine, U.S.A. Five sets had two parallel strings of five opposing shelters and an additional linear string set 2 m apart without opposing shelters was the most widely separated treatment. Shelters spaced 1 m apart and closer had higher lobster population densities, more intraspecific competition and higher proportions of empty shelters. Surprisingly, lobsters there were also significantly smaller, declining from 62.7 mm to 50.8 on the carapace (CL) for 2 m linear to 0.25 m spaced shelters, respectively. Nearly all 932 lobsters measured in this study were juvenile (< 90 mm CL) and preharvestable (<83 mm CL) sized, so mate selection and fishing effects were unlikely. At the scale of the experiment, larger lobsters leave or avoid areas of high lobster population density and intense competition for areas of low population density and relaxed competition (called “demographic diffusion”). Scuba surveys in coastal zones found lobster population densities scale with shelter densities and were highest in boulder habitat where, like the experiment, more than half the shelters were vacant. Fisheries independent scuba and trawl surveys in Maine's shallow coastal zone repeatedly recorded declines of preharvestable lobsters larger than 60 mm CL in size and increases of those sizes offshore and in deep water. It is possible that this demographic diffusion is driven by behaviors associated with intraspecific shelter competition.

Affiliations: 1: University of Maine, 193 Clark's Cove Road, Darling Marine Center, Walpole, Maine 04573, U.S.A. (


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1. Acheson J. M. , Steneck R. S. 1997 "Bust and then boom in the Maine lobster industry: perspectives of fisheries and biologists." North American Journal of Fisheries Management Vol 17 826 847
2. ASMFC (Atlantic States Marine Fisheries Commission). 2000 "American lobster stock assessment report for peer review. Stock Assessment Report No. 00-01 (supplement)." Atlantic States Marine Fisheries Commission, Washington, D.C. 532 pp
3. Atema J. 1986 "Review of sexual selection and chemical communication in the lobster, Homarus americanus." Canadian Journal of Fisheries and Aquatic Sciences Vol 43 2283 2390
4. Atema J. , Cobb J. S. 1980 "Social behavior, pp. 409-450." In, J. S. Cobb and B. F. Phillips (eds.), The Biology and Management of Lobsters. Vol. 1. Academic Press, New York. New York
5. Butler M. , Herrnkind W. , Steneck R. S. 2006 "The ecology of juvenile and adult lobsters." In, B. F. Phillips (eds.), The Ecology and Management of Lobsters. In press
6. Caddy J. F. 1986 "Modeling stockrecruitment processes in Crustacea: some practical and theoretical perspectives." Canadian Journal of Fisheries and Aquatic Sciences Vol 43 2330 2344
7. Campbell A. , Pezzack D. S. 1986 "Relative egg production and abundance of berried lobsters, Homarus americanus, in the Bay of Fundy and off southwestern Nova Scotia." Canadian Journal of Fisheries and Aquatic Sciences Vol 43 2190 2196
8. Chen Y. , Sherman S. , Wilson C. , Sowles J. , Kanaiwa M. 2006 "A comparison of two fishery-independent survey programs in characterizing population structure of American lobster, Homarus americanus, in the Gulf of Maine." Fishery Bulletin in press
9. Cobb J. S. 1971 "The shelter-related behavior of the lobster, Homarus americanus." Ecology Vol 52 108 115
10. Cobb J. S. 1977 "Review of the habitat behaviour of the clawed lobsters (Homarus and Nephrops). pp. 143-157." In, B. F. Phillips and J. S. Cobb (eds.), Division of Fisheries and Oceanography Circular 7. Commonwealth Scientific and Industrial Research Organization, Melbourne, Australia
11. Cobb J. S. 1995 "Interface of ecology, behavior and fisheries. pp. 139-151." In, J. R. Factor (ed.), Biology of the Lobster, Homarus americanus. Academic Press, San Diego
12. Cobb J. S. , Tamm G. 1975 "Dominance status and molt order in lobsters (Homarus americanus)." Marine Behavior Physiology Vol 3 119 124
13. Cobb J. S. , Tamm G. , Wang D. 1982 "Behavioral mechanisms influencing molt frequency in the American lobster (Homarus americanus)." Journal of Experimental Marine Biology and Ecology Vol 62 185 200
14. Cobb J. S. , Wahle R. 1994 "Early like history and recruitment processes of clawed lobsters." Crustaceana Vol 67 1 25
15. Cooper R. A. , Uzmann J. R. 1980 "Ecology of Juvenile and Adult Homarus. pp. 97-141." In, J. S. Cobb and B. F. Phillips (eds.), The Biology and Management of Lobsters. Vol. 2. Academic Press, New York, New York
16. Fogarty M. J. 1995 "Populations, fisheries, and management. pp. 111-138." In, J. R. Factor (ed.), Biology of the Lobster, Homarus americanus. Academic Press, San Diego
17. Hacker S. D. , Steneck R. S. 1990 "Habitat architecture and the abundance and body-size-dependent habitat selection of a phytal amphipod." Ecology Vol 71 2269 2285
18. Huntingford F. A. , Turner A. K. 1987 "Animal Conflict." Chapman and Hall, London, New York. 469 pp
19. Jacobson L. D. 2001 "Long time series of NEFSC bottom trawl survey data for American lobster." National Marine Fisheries Service. Unpublished Data
20. Krouse J. , Thomas J. 1975 "Effects of trap selectivity and some population parameters on size composition of the American lobster, Homarus americanus, and catch along the Maine coast." Fishery Bulletin Vol 73 862 871
21. Lawton P. , Lavalli K. L. 1995 "Postlarval, juvenile, adolescent, and adult ecology. pp. 47-88." In, J. F. Factor (ed.), Biology of the Lobster Homarus americanus. Academic Press, Inc., New York
22. O'Neill D. J. , Cobb J. S. 1979 "Some factors influencing the outcome of shelter competition in lobsters (Homarus americanus)." Marine Behavior Physiology Vol 6 33 45
23. Palma A. T. , Wahle R. A. , Steneck R. S. 1998 "Different early post-settlement strategies between American lobsters Homarus americanus and rock crabs Cancer irroratus in the Gulf of Maine." Marine Ecology Progress Series Vol 162 215 225
24. Palma A. T. , Steneck R. S. , Wilson C. 1999 "Settlement-driven, multiscale demographic patterns of large benthic decapods in the Gulf of Maine." Journal of Experimental Marine Biology and Ecology Vol 241 107 136
25. Ricklefs R. E. 1990 "Ecology. Third edition." W. H. Freeman and Company, New York
26. Sherman S. A. , Manfredi V. , Brown J. , Stepanek K. , Sowles J. , Grout D. , Tetrault R. 2003 "Final Report Fall 2002 and Spring 2003 MaineNew Hampshire inshore trawl survey." Maine Department of Marine Resources Reference Document 04/02
27. Skud B. E. , Perkins H. C. 1969 "Size composition, sex ratio, and size at maturity of offshore northern lobsters." U. S. Fish and Wildlife Service Special Scientific Report Vol 598 1 10
28. Sokal R. R. , Rohlf F. J. 1995 "Biometry. Third edition." W. H. Freeman and Company, New York. 1-887 pp
29. Steger R. 1987 "Effects of refuges and recruitment on gonodactylid stomatopods, a guild of mobile prey." Ecology Vol 68 1520 1533
30. Steneck R. S. 1989 "The ecological ontogeny of lobsters: in situ studies with demographic implications." In, I. Kornfield (ed.), Proceedings Lobster Life History Workshop, Orono, Me Vol 1 30 33
31. Steneck R. S. 1997 "Fisheries-induced biological changes to the structure and function of the Gulf of Maine Ecosystem. Plenary Paper. pp. 151-165." In, G. T. Wallace and E. F. Braasch, eds. Proceedings of the Gulf of Maine Ecosystem Dynamics Scientific Symposium and Workshop. RARGOM Report, 97-1. Regional Association for Research on the Gulf of Maine. Hanover, New Hampshire
32. Steneck R. S. 2006) "Is the American lobster, Homarus americanus overfished? A review of overfishing with an ecologically-based perspective." Marine Sciences Bulletin Vol 78 607 632
33. Steneck R. S. , Wilson C. J. 2001 "Large-scale and long-term, spatial and temporal patterns in demography and landings of the American lobster, Homarus americanus, in Maine." Marine Freshwater Research Vol 52 1303 1319
34. Steneck R. S. , Graham M. H. , Bourque B. J. , Corbett D. , Erlandson J. M. , Estes J. A. , Tegner M. J. 2002 "Kelp forest ecosystem: biodiversity, stability, resilience and their future." Environmental Conservation Vol 29 436 459
35. Steneck R. S. , Vavrinec J. , Leland A. V. 2004 "Accelerating trophic level dysfunction in kelp forest ecosystems of the western North Atlantic." Ecosystems Vol 7 323 331
36. Wahle R. A. 2003 "Revealing stock-recruitment relationships in lobsters and crabs: is experimental ecology the key?." Fisheries Research Vol 65 3 32
37. Wahle R. A. 1992 "Body-size dependent antipredator mechanisms of the American lobster." Oikos Vol 63 1 9
38. Wahle R. A. , Steneck R. S. 1991 "Recruitment habitats and nursery grounds of the American lobster, Homarus americanus: a demographic bottleneck?." Marine Ecology Progress Series Vol 69 231 243
39. Wahle R. A. , Steneck R. S. 1992 "Habitat restrictions in early benthic life: experiments on habitat selection and in situ predation with the American lobster." Journal of Experimental Marine Biology and Ecology Vol 157 91 114
40. Wahle R. A. , Incze L. S. 1997 "Pre- and post-settlement processes in recruitment of the American lobster." Journal of Experimental Marine Biology and Ecology Vol 217 179 207
41. Wahle R. A. , Incze L. S. , Fogarty M. J. 2004 "First projections of American lobster fishery recruitment using a settlement index and variable growth." Bulletin of Marine Sciences Vol 74 101 114
42. Witman J. D. , Sebens K. P. 1992 "Regional variation in fish predation intensity: a historical perspective in the Gulf of Maine." Oecologia Vol 90 305 315

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