David Secord

Biological control of marine invasive species: cautionary tales and land-based lessons

Biological control (biocontrol) has successfully regulated pest populations in terrestrial agroecosystems, but it has also caused negative unintended consequences for native species. Marine biologists and resource managers have recently published a growing number of proposals to include biocontrol in integrated pest management programs in oceans, seas and estuaries. Here, I review six ecologically and taxonomically diverse case studies of marine biocontrol programs at various stages of planning and implementation. Proposals include viral or microbial control of harmful algal blooms, predatory control of the ctenophore Mnemiopsis leidyi in the Black Sea, parasitic regulation of the European green crab Carcinus maenas, castration by ciliates of the seastar Asterias amurensis in Australia, herbivory of the toxic green alga Caulerpa taxifolia in the Mediterranean by sacoglossan sea slugs, and insect biocontrol by the planthopper Prokelesia marginata to ameliorate ecological impacts of the saltmarsh cordgrass Spartina alterniflora. Where data exist, I evaluate these examples in terms of lessons marine invasion biologists can glean from the rich history of terrestrial biocontrol, and explicitly contrast agroecosystems with invaded marine habitats. Host specificity cannot be guaranteed in the marine biocontrol proposals examined. Feasible alternatives to classical biocontrol in the marine realm should be emphasized, including more investment in invasion prevention tools, early detection and eradication while invasions are small, and increased attention to native natural enemies to control exotic pests. Biocontrol in marine habitats is risky: it poses many more uncertainties and has a much sparser history than its counterpart on land.

Symbioses and their Consequences for Community and Applied Ecology

Species interactions are frequently variable in time and space, and symbiotic relationships are certainly no exception. Empirically derived rules of host specificity and interspecific interactions may apply locally under some conditions, but we must exercise care when we extrapolate results across species’ ranges or when local conditions change. In the words of the ecologist Larry Slobodkin (1987), “the study of symbiosis should remain elegant natural history, combined with the full spectrum of modern biology at all levels.” The level of community ecology has historically been somewhat lacking! An interdisciplinary mix of approaches and insights will be necessary as conservation biologists, population and community ecologists, resource managers, epidemiologists, and symbiosis researchers tackle basic and applied problems in habitats as diverse as old growth forests, coral reefs, and agroecosystems. A marriage of the data and methods of field ecology with laboratory analysis of the physiological and biochemical details of symbiosis, and increasing interactions among community ecologists and symbiologists, will nudge biological science and its applications farther along this necessary path.

Assembling the Pieces of the Invasive Species Puzzle

Mooney, Harold A., Richard N. Mack, Jeffrey A. McNeely, Laurie E. Neville, Peter Johan Schei, and Jeffrey K. Waage, editors. 2005. Invasive alien species: a new synthesis. SCOPE 63. Island Press, Washington, D.C. xvii + 368 p.

TROUBLE ON OILED WATERS: Lessons from the Exxon Valdez Oil Spill

70.00 (cloth), ISBN: 1-55963-362-X (alk. paper);

Biogeography and microhabitat variation in temperate algal‐invertebrate symbioses: zooxanthellae and zoochlorellae in two Pacific intertidal sea anemones, Anthopleura elegantissima and A. xanthogrammica

35.00 (paper), ISBN: 1-55963-363-8 (alk. paper).