Literature Cited. Montana State University, Bozeman, MT

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1 vation work of several individuals or organizations. Award recipients in 1987 were Paul Ehrlich for his basic research on animal population dynamics and his applied research on the human population explosion and its consequences; Norman Myers for his continuing efforts to draw public attention to the problem of tropical forest destruction; Michael Lennartz and his associates for their work with the endangered Red-cockaded Woodpecker; and the New York Zoological Society for its leadership in conservation biology (Brussard 1987). Award recipients in 1988 were Michael Bean of the Environmental Defense Fund for his contributions to conservation as an attorney and author; the Jersey Wildlife Preservation Trust for its pioneering work in conservation biology and for its training program in conservation biology for scientists from developing countries; Raymond Dasmann for his contributions to the science of wildlife biology; the Interagency Grizzly Bear Committee for its leadership in promoting cooperation of state and federal governments in saving the grizzly bear; and Devra Kleiman for her studies of mammalian behavior and reproductive and for applying her discoveries to solving conservation problems. Normal Myers presented a lecture about the destruction of tropical rain forests at the 1987 banquet. No formallecture was given at the 1988 banquet. The next Society for Conservation Biology meeting will be held in conjunction with the 40th AlBS annual meeting at the University of Toronto, Canada, 6-10 August The theme of the AlBS meeting is "Global Change." For more information about the 1989 meeting, contact Peter Brussard, SCB Secretary-Treasurer, Department of Biology, Montana State University, Bozeman, MT Literature Cited Brussard, P. F The current status of conservation biology. ESA Bulletin 66(1): Meeting report. Conservation Biology 1 (3): Ginsberg, J. R What is conservation biology? Trends in Ecology and Evolution 2: Soule, M. E What is conservation biology? BioScience 35: History of the Society for Conservation Biology: how and why we got here. Conservation Biology 1(1):4-5. Temple, S. A., E. G. Bolen, M. E. Soule, P. F. Brussard, H. Salwasser, and J. G. Teer What's so new about conservation biology? Pages in Transactions of the 53rd North American Wildlife and Natural Resources Conference. Tim W. Clark and Ann H. Harvey Northern Rockies Conservation Cooperative P.O. Box 2705 Jackson, WY and Jennifer M. Tuteur Yale University Box 7200 New Haven, CT LONG-TERM RESEARCH AT THE NATIONAL MARINE MAMMAL LABORATORY The National Marine Mammal Laboratory (NMML) was established in 1978 by the National Marine Fisheries Service (NMFS), apart of the National Oceanic and Atmospheric Administration (NOAA), to study the life history and population dynamics of whales, dolphins, porpoises, seals, and sea lions, worldwide. The purpose of research at the NMML is to address identified problems by conducting directed and basic research to meet legislative requirements and to help resolve issues concerning the agency's management of marine resources. This paper reviews those scientific programs at the NMML that help support NMFS's marine ecosystem management initiative. Research priorities were developed from recommendations derived from program re- 21

2 Table 1. Long-term studies at the National Marine Mammal Laboratory. Study sites and species Pribilof Islands San Miguel Island California sea lion No. elephant seal Central California Gray whale St. George Island Point Barrow Bowhead whale Eastern No. Pacific Dall's porpoise Eastern Aleutian Is. No. sea lion Marmot Island No. sea lion Puget Sound California sea lion Harbor seal Harbor porpoise Seallsland Antarctic fur seal Penguins Length of study (actual year) 48 years ( ) 21 years ( ) 18 yearst ( , ) 15 years ( ) 13 years+ ( ) 10 years ( ) 10 years (1969, , ) 3 years 3 years 2 years Research problems Population trends in relation to commercial harvest and depletion Community ecology, population trends, and fisheries interactions Population recovery of an endangered species Survival and reproduction in the absence of a commercial hunt Population recovery and life history of an endangered species Incidental take, life history, and stock identification Census and life history of a declining species, and fisheries interactions Census and reproduction of a declining species Fisheries interactions, food habits, and population trends Population abundance, feeding ecology, and reproductive success Fur seal studies on the Pribilol Islands were initiated in t 872. and valuable but intermittent data ware coilected up to (None in 1942.) t The first shore count 01 gray whales was conducted in and olhers ware conducted intermittently in this century to * Bowhead whale Held studies were not conducted in This continues research on northem sea lions done by the Alaska Department 01 Fish and Garne in the 1970s. views conducted with peers from science and management. Priority was given to determining the causes of population change, the nature of ecological processes, the utility of expanding existing data bases, and if research is practical and feasible given the available resources and logistic constraints. Based on these priorities, research was designed to address the questions: Why have some seal and sea lion populations declined, and are they still declining? Why have other populations of seals and sea lions increased, and what are the effects on marine resources and fisheries? Are fisheries having an effect on the conservation of marine mammals? Are depleted and endangered species recovering? Long-term studies are carried out at selected sites from the Arctic to the Antarctic (Table 1). For the next several years, the fol- lowing research activities will be conducted assuming stable funding. Other important research topics have been recommended but cannot be addressed at this time. Antarctic.-Monitoring changes in ecological relationships between components of the marine ecosystem is an important element of the Ecosystem Monitoring Program under the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR). Since not all ecosystem components can be monitored simultaneously, the CCAMLR has endorsed a scientific program that focuses on predators, prey, and environmental conditions. Under NOAA's Antarctic Marine Living Resources (AMLR) Program, we have initiated research on Antarctic fur seals, Arctocephalus gazella, southern elephant seals, Mirounga leonina, crabeater seals, Lobodon 22

3 eareinophagus, leopard seals, Hydrurga /eptonyx and chinstrap, Pygoscelis antaretiea, macaroni, Eudyptes ehrys%phus, and Adelie penguins, Pygoscelis adeliae. Changes in these populations are monitored by assessing foraging patterns, prey availability, and reproductive success trom tagging experiments, and by determining trends in abundance. Mapping the distribution and density of whales from commercial whaling records has been completed as a first step in identifying seasonal distribution, and, possiblly, habitat-use patterns in relation to feeding areas. Aretie.-Under the Arctic Research and Policy Act of 1984, the National Science Foundation and the Interagency Arctic Research and Policy Committee have recommended research on the enumeration and life history of bowhead whales, Ba/aena mystieetus, beluga whales, De/phinapterus /eueas, and the pagophilic ("ice loving") seals. High priority was also given to studying the ecology of polynyas (i.e., open water areas in pack ice), to determine their role in the natural history of Arctic wildlife. The bowhead whale population in the western North American Arctic is thought to have been severely reduced by commercial whaling at the turn of the 20th century. Since about 1920 Alaskan Eskimos have taken wh ales per year for subsistence. To assess the recovery of this endangered species, research has focused on recruitment, survival, age structure, and population size (Nerini et al. 1984). Dur most recent assessment indicates that the Eskimo take has not caused the bowhead population to decline, and it may be increasing (Breiwick et al. 1984). Lengths of individuals, calf production, and the proportion of mature animals in the population are estimated trom aerial photogrammetry conducted during the whale's spring migration near Point Barrow, Alaska. Length and estimated age at first reproduction, calving intervals, and population size are estimated from multiple sightings of naturally marked individuals. Bering Sea and Gulf of A/aska.-Although the living marine resources of the Bering Sea and Gulf of Alaska include some of the most abundant stocks in the Northern Hemisphere, we know little about their interrelations, trophic dynamics, or natural regulation of populations. Two species, the northern fur seal, Ca/ /orhinus ursinus, and northern sea lion, Eumatopias jubatus, have declined by 50% in the past decade (Merrick et al. 1987; York 1987: Figs. 4-5). These species may be affected by competition, predation, fisheries' takes, entanglement, and intentional killing, and possibly by ecosystem changes in ways that are not weil understood. Currently studies are being conducted on fur seal and sea lion population dynamics, life history and fisheries interactions. Long-term tagging is being evaluated for study of changes in reproduction and survival. Adult male fur seals are counted at all rookery sites on the Pribilof Islands. Estimates of pup production, sex ratios, mortalityon land, disease conditions, and incidental take are also documented. Studies will investigate weaning and productivity, and examine the evolutionary ecology of reproductive strategies, comparing sea lions and fur seals. Because the reproductive potential of a population is ultimately limited by the number of adult females, longterm tagging of female fur seals has been started to monitor trends in age at first reproduction, pregnancy rates, fecundity, and cohort survivorship. The influence of water temperature and storm conditions on the survival of sea lions and fur seals will be addressed. Lastly, the distribution, pod identity, and feeding behavior of killer whales, Oreinus orea, are being studied relative to the Sablefish, Amop/opoma fimbria, longline fishery, and the mortality of newly weaned fur seal pups. California Current.-Pinniped populations along the Pacific west coast south of Alaska have been growing rapidly since the 1970s. Preliminary assessments indicate that harbor seal, Phoea vitulina, northern elephant seal, Mirounga angustirostris, California sea lion, Za/ophus ealifornianus, and northern fur seal populations may still be below their "optimum sustainable population" levels (i.e., that range between levels resulting in maximum net productivity and carrying capacity), suggesting they may increase further. Additional information is needed on the population dynamics, food habits, fisheries interactions, and life history of coastal pinnipeds to determine what measures are necessary, if any, to help resolve the conflicts between burgeoning pinniped populations and coastal fisheries, and to evaluate environmental effects on population growth. To study these problems, the condition of individual pinnipeds, as an index to the health of a popu- 23

4 lation, is obtained. Tagging and radio tracking are conducted to monitor abundance, reproductive success, and feeding habits. For pinnipeds from San Miguel Island, California, analyses of pup weights, survival, and other indices are underway to help us determine what effects EI NiJio events have on pinniped populations. For example, the EI NiJio warm water event of reduced the reproductive output of northern fur seals on San Miguel Island by 60% in 1984, but it reduced California sea lions by only 10%. In Puget Sound, Washington, pinniped-salmonid fisheries interactions are investigated by documenting incidental take of pinnipeds and damage to caught fish. Information on feeding habits of pinnipeds associated with the fisheries is obtained from animals caught in the nets, in fecal scats from animals hauled out on land, and sampling prey. Long-term studies will focus on annual production, population growth rates, and survival rates of harbor seals and California sea lions. The incidental take and ecology of harbor porpoise, Phocoena phocoena, are also being investigated to determine wh at effect set-net fisheries are having on the status of this littlestudied cetacean. Ecosystem and population assessments. Considerable data exist on northern fur seals, Dall's porpoise, and commercially landed large wh ales. A synthesis of these data is underway to evaluate which questions to ask for further studies, and how to interrelate information from other disciplines for population simulations and ecosystem modeling. Modeling is being carried out on changes in population parameters to evaluate the role marine mammals play in the ecosystem, and to make stock assessments (e.g., trend analyses). A model will be developed to integrate data from environmental assessments, population biology, and commercial fisheries as a working simulation of the trophic-dynamic relationships of marine mammals in the eastern North Pacific. Analyses will also be performed on relevant problems such as population-level changes in relation to diseases, fishery-related mortality, EI Nirio and other natural environmental conditions, and characterization of historical population levels based on life history events. In addition to modeling, population assessments are routinely conducted. Revisions in the status of northern fur seals are being made by assessing the role fisheries may have on population change, such as the effects of entanglement (Fowler 1987). Under the Endangered Species Act of 1973 a status review of endangered and threatened marine mammals is underway, and is conducted every five years. Also, a full assessment of gray whales, Eschrichtius robustus, is being undertaken, following 18 years of census data. Our computerized photographic identification system will be updated and cooperative investigations explored with scientists in the North Pacific for the study of life history and population biology of humpback whales, Megaptera novaeangliea. High seas fisheries interactions.-marine mammals and seabirds are accidentally taken in high seas driftnet fisheries in the North Pacific and southern Bering Sea in and outside the U.S. Exclusive Economic Zone (EEZ). Long-term studies begun in 1978 on the incidental take and effects of high seas salmon driftnet fisheries on Dall's porpoise, Phocoenoides da/li, have emphasized abundance, distribution, life history, behavior, feeding ecology, and stock discreetness (Winans and Jones 1988). Incidental take data have been obtained, by area, fishery, and species, by placing observers on foreign commercial and research vessels. Biological sampies have been collected from Dall's porpoise taken in gillnets, to evaluate reproductive rates, condition of individuals, and feeding habits, for comparison over time, between areas and stocks. While much is known about the Japanese salmon fishery, little is known about the multination squid driftnet fishery operating outside the U.S. EEZ. High seas squid gillnet fishing began in the late 1970s and expanded to more than 700 vessels, each fishing km of gillnet per night from April to January. Several species of marine mammals and birds are incidentally taken. An unknown fraction of those that entangle die, and there is essentially no information on the magnitude or effects of the takes, nor is there a coordinated research program to investigate the ecology of marine mammals at sea in relation to driftnet fishing. "... judicious monitoring of ecological processes is a crucial activity which needs to be legitimized, and funding... ought to reflect this need... " (Likens et al. 1987). Long-term studies are afforded high priority at the NMML but they require a commitment to long-range 24

5 funding. The Congress of the United States, NOAA, and NMFS have made that commitment to the extent that the budget and statt size (42) have not changed significantly since Inflation and redirected cuts, however, have resulted in a significant decline in operating funds (r= 0.775, P<.01). Nevertheless, productivity is high, with annual publications averaging 35 per year for the past 11 years and 90% appearing in the peer literature. The future of marine mammal research is largely dependent on the growth and direction of fisheriies, conservation issues, and how the study of ecosystems is to be achieved. A recent fisheries-conservation community cooperative initiative for reauthorization of the Marine Mammal Protection Act is a positive sign in easing potential conflicting positions on marine mammal issues. In addition, studies of marine ecosystems by the NMFS are being designed to understand the interactions between competing resources. To accomplish this aim, basic research is needed on the natural history of marine mammal populations and ecological processes. Current long-term studies at the NMML will not fully meet these needs but they are intended to develop the information upon which further theoretical and applied research can be carried out. Acknow/edgments John Bengtson, Robert DeLong, Charles Fowler, Roger Gentry, Linda Jones, Thomas Loughlin, R. V. Miller, Mary Nerini, Norris Jeffery, and Gary Stautter each made significant contributions, as did William Aron and several others during program reviews. I also thank Vera Alexander (University of Alaska), Paul Dayton (Scripps Institution of Oceanography), and Rodger Mitchell (The Ohio State University) and three anonymous reviewers. David Withrow, Leola Hietala, and Karen Conlan assisted. Literature Cited Breiwick, J. M., L. L. Eberhardt, and H. W. Braham Population dynamics of western Arctic bowhead wh ales (Ba/aena mysticetus). Canadian Journal of Fisheries and Aquatic Science 41 : Fowler, C. W Marine debris and northern fur seals: a case study. Marine Pollution Bulletin 18: Likens, G. E., J. J. Cole, J. Kolasa, J. B. McAninch, M. L. McDonnell, G. G. Parker, and D. L. Strayer Status and future of ecosystem science. First Cary Conference. Occasional Publications of the Institute of Ecological Studies, New York Botanical Gardens, Number 3. Merrick, R. L., T. R. Loughlin, and D. G. Calkins Decline in abundance of the northern sea lion, Eumatopias jubatus, in Alaska, Fishery Bulletin 85: Nerini, M., H. Braham, W. Marquette, and D. Rugh Life history of the bowhead wh ale, Ba/aena mysticetus. Journal of Zoology (London) 204: Winans, G., and L. Jones Electrophoretic variability in Dall's porpoise (Phocoenoides dalli) in the North Pacific Ocean and Bering Sea. Journal of Mammalogy 69: York, A. E Northern fur seal, Callorhinus ursinus, eastern Pacific population (Pribilof Islands, Alaska, and San Miguel Island, California). U.S. Department of Commerce, National Oceanic and Atmospheric Administration (NOAA) Technical Report NMFS 51 :9-21. Howard W. Braham National Marine Mammal Laboratory Northwest and Alaska Fisheries Center National Marine Fisheries Service, NOAA 7600 Sand Point Way, N.E. Seattle, WA A FRAMEWORK FOR COMPARATIVE STUDIES IN FOREST DYNAMICS: THE GAP-SNAP-DRAP-SAP-NAP-CRAP MODEL When falling trees create a GAP, compesition of the ensuing vegetation can have five origins (Fig. 1): SAPs, or previously suppressed saplings of canopy species, involved in advanced regeneration (cf. Uhl et al. 1988); SNAPs, or broken-ott pre-disturbance plants that re-sprout (cf. Putz and Brokaw 1989; 25