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About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please CONSERVATION CONFLICTS BETWEEN SPECIES 115 BOX 6-2 CHINOOK SALMON AND DELTA SMELT Four races of chinook salmon (Oncorhynchus tshawytscha) inhabit the Sacramento River system. The winter-run race migrates upstream in the winter. Although it was previously abundant in this drainage system, population sizes have declined drastically, from an estimated 117,808 individuals in 1969 to 341 in 1992/93 (FWS, 1992). This race is now listed as endangered on the Federal Endangered Species List (Fed. Reg. 59:13836). Adults migrate as far up the Sacramento River as possible in the winter, with spawning as early as mid-April, reaching a peak in June, and then declining through the summer until August. Eggs are incubated for 40-60 days followed by an additional 2-4 weeks for the newly hatched fry on gravel substrate. Incubation must occur in cool water temperatures (43-58°F), although incubation occurs during the hottest time of the year. Migration of the juveniles begins after a short period of growth, with juveniles migrating to the lower river up to a year after the beginning of spawning of their cohort. The delta smelt (Hypomesus transpacificus) is endemic to the Sacramento-San Joaquin River estuary. The entire species is listed as threatened on the Federal Endangered Species List (Fed. Reg. 58:12863). Compared with salmon, the smelt has a short life span. Spawning occurs primarily from December to March. Eggs hatch 10-12 days after fertilization into larvae that drift downstream with the river current. By one year of age the fish are sexually mature, with mating of a cohort continuing into the summer of the year after hatching. Although the biology of this species is not known in detail, it appears that adults die soon after spawning. The delta smelt is associated with well-oxygenated, very cold water. It also appears that hard substrates and submerged rocks are needed for successful spawning Two major water projects, the Central Valley Project (CVP) and the State Water Project (SWP), and many smaller diversions affect these species both in the Sacramento-San Joaquin delta and the Sacramento River (for the winter-run chinook salmon). These water diversions can entrain fish along the diverted flows as well as reduce flows downstream. Flow diversions and impoundment storage behind dams can greatly alter flows, flow pattern, and seasonality. Flows also affect movement of fish, particularly larvae of delta smelt and striped bass. In addition, flows play a major role in the location of highly productive areas for phytoplankton and zooplankton. An "entrapment" or "null" zone that provides important nursery habitat for delta smelt and striped bass is typically formed in Suisun Bay downstream of the delta. During drought years, this zone occurs in the channel of the delta much closer to the CVP and SWP water intakes than in normal years. During such periods, entrainment is expected to be increased. In addition, production of prey organisms is expected to decrease because of the smaller size of the delta channels. An additional problem associated with the major water projects is increased predation by fish-eating predators, including adult striped bass, which use features of the major intakes to prey on smaller fish. Such predation is considered to be one of the major sources of loss associated with the SWP. use the print version of this publication as the authoritative version for attribution.

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About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please CONSERVATION CONFLICTS BETWEEN SPECIES 116 the central delta while increasing the San Joaquin and Mokelumne rivers flows to the pumps. Delta smelt will be adversely affected, however, because they will be in these waters at the times of reduced flows, and entrainment at the Tracy pumping plant might increase. Moreover, striped bass are probably predators of the smelt, so this action could result in increased mortality of the smelt. Another provision, Provision 18, advocates restoration of the striped bass fishery, which would also have an adverse effect on the delta smelt due to increased predation (see Box 6-2). It is apparent that the Central Valley Improvement Act attempts to correct many problems that the Central Valley Project causes for threatened and endangered fish and that, in some cases, actions will benefit all of the species involved. However, in some situations, management techniques that are most beneficial to one threatened species adversely affect the other. In this system, the situation is complicated by the presence of a third species, striped bass, that is being considered because of public interest. Tradeoffs will have to be evaluated in each case to determine what measures should be implemented. For example, additional flow releases without additional pumping after delta smelt spawning could benefit that species by carrying eggs and larvae past the pumps to Suisun Bay where the best rearing habitats occur during normal flow years. Other actions affecting these species include the water-quality standards set by the U.S. Environmental Protection Agency to protect the delta. Those standards (Fed. Reg. 59:810-852) will result in increased flows and decreased pumpings, which should help normalize salt levels and provide larger quantities of water to facilitate migration conditions and rearing. In addition, the State Water Resource Control Board is under federal court mandate to impose standards and regulations as well. Such judicial and regulatory actions have resulted in pumping restrictions at the State Water Project and Central Valley Project to reduce losses of winter-run salmon and delta smelt. Nevertheless, it is unclear whether these actions will be able to help both species, or if one will still suffer at the expense of the other. BACHMAN'S SPARROW AND RED-COCKADED WOODPECKER Management decisions designed to improve conditions for a threatened or endangered species may inadvertently affect dozens of nontarget species found in the same habitats. Possible effects on nontarget species are rarely assessed before implementation of management actions. It will become increasingly important to develop tools to assess the effect of proposed management strategies on a wide variety of organisms as federal agencies and others put increased emphasis on management for biodiversity. use the print version of this publication as the authoritative version for attribution.

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About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please CONSERVATION CONFLICTS BETWEEN SPECIES 117 Several research groups are developing population simulation models linked to Geographical Information System (GIS) maps that capture some of the complexity of real-world landscapes and allow simultaneous consideration of the responses of many different species to management proposals. This approach requires, at a minimum, a good understanding of the habitat requirements of the species of interest, and a realistic landscape map that shows the locations of current and future suitable habitat as a function of management decisions. More recent versions of these models also require detailed information on habitat-specific demography and dispersal behavior. Liu (1992) and Liu et al. (1995) give one example of the use of such models to forecast how management plans largely designed for one endangered species might affect a nontarget species. Liu et al. (1995) used a mobile animal populations model (Pulliam et al., 1992) (Chapter 5) to determine how the Bachman's sparrow (Aimophila aestivalis), a declining species of management interest in the southeastern United States, might respond to a management strategy largely designed to favor populations of the endangered red-cockaded woodpecker (Picoides borealis) (see Box 6-3). The results of such models are useful in a variety of ways. In the particular case discussed, the model allowed alternative cutting and thinning plans to be explored, at least some of which allowed larger populations of sparrows, as well as woodpeckers, to be maintained. Models of this sort can also incorporate economic considerations (Angelstam, 1992; Liu et al., 1994) and might prove useful in future attempts to balance ecological and economic goals. However, caution must be exercised in using models of this sort for management decisions, because the models are not yet fully quantified or tested against field results. A prudent use of such models would be in the context of adaptive ecosystem management. Here, the models would be used to generate testable hypotheses, and forest-management practices would be used as an experiment to test the model predictions. MARINE MAMMALS AND SALMONIDS The effect of predation by marine mammals on salmonids has been controversial since at least the 19th century (Merriam, 1901). In 1899, the president of the California Board of Fish Commissioners proposed to kill "10,000 of the 30,000 [California sea lions, Zalophus californianus, and Steller's sea lions, Eumatopias stelleri] that now infest our harbor entrances and contiguous territories" to reduce their alleged depredations on salmon. Merriam pointed out that there probably weren't even 10,000 sea lions on the coast. He described the work of L.L. Dyche, who examined the stom use the print version of this publication as the authoritative version for attribution.

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About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please CONSERVATION CONFLICTS BETWEEN SPECIES 119 were completed in 1917 as part of a project of the U.S. Army Corps of Engineers to allow ship traffic between Puget Sound and Lake Washington (Willingham, 1992). Previously, the lake had drained through the Black River, which flowed into the Cedar and Green rivers and then into Puget Sound. The current drainage into Puget Sound is through the Lake Washington Ship Canal, Lake Union, and the Ballard locks. Steelhead trout (Oncorhynchus mykiss) migrated through Lake Washington to spawn in its tributaries before 1917; they do so today. The runs consist of wild and hatchery fish, but the hatchery program has been discontinued recently (Fraker, 1994). Although some people believed the current runs were derived from hatchery fish, genetic analysis indicates that they are probably descendants of the original wild runs (Fraker, 1994). Lake Washington steelhead are winter-run fish, returning to the fresh water to spawn from December to April. As the fish enter the ship canal below the locks, some of them are captured and eaten by California sea lions. The first observation of such predation was made in 1980; by the mid-1980s there were as many as 60 sea lions in the area around the locks and more than 50% of the returning steelhead were being eaten. (Between 51% and 65% were taken each year up to 1992, except for 1985-1986 (15%) and 1986-1987 (41%), when predator- control efforts had some success.) The number of fish in the run that escaped to spawn, which ranged from 474 to 2,575 fish from 1980-1981 to 1985-1986, declined to 184 fish in 1992-1993 (Fraker, 1994) and to 70 in 1993-1994 (NMFS and WDFW, 1995). It is clear that sea lions have affected the Lake Washington steelhead run, but they are not entirely responsible for its recent decline. Cooper and Johnson (1992) found that steelhead had declined generally since 1985. They considered the following items to be possible contributing factors: competition for food with other salmon, in particular, 8 billion hatchery salmon released since the late 1980s; authorized and unauthorized drift- net fisheries (probably not currently a factor); predation by birds and mammals; and large-scale environmental changes. Predation by marine mammals is probably not a major factor in the current decline of salmon in general. Anadromous salmonids and marine mammals coexisted for thousands of years before the current declines in salmonids, and California and Steller sea lions were much more abundant in the first half of the 19th century—a time when salmon were also abundant—than later. And marine mammals do not normally specialize on salmonids; they eat a wide variety of prey items, determined by what is available and how easy it is to catch (Gearin et al., 1988; Fraker, 1994; Olesiuk, 1993). Finally, the Ballard locks area provides a local concentration of fish in space and time, and they have few refuges there, and sea lions congregate there in large numbers (Fraker, 1994). use the print version of this publication as the authoritative version for attribution.

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About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please CONSERVATION CONFLICTS BETWEEN SPECIES 120 However, many marine-mammal populations are increasing, at least partly because of the protections of the Marine Mammal Protection Act (MMPA). California sea lions now number more than 100,000 (Fraker, 1994). Other human activities, combined with increasing marine-mammal populations, could cause increasing problems, especially in areas where the fish congregate, as in the case of the steelhead at Ballard. If the Lake Washington steelhead were listed as endangered or threatened under the Endangered Species Act, the conflict would be brought into sharper focus by the requirements of the Endangered Species Act and the MMPA. Indeed, the MMPA was amended in 1994 to allow the killing of marine mammals under particular circumstances, and Washington state has filed a petition to remove sea lions from the Ballard locks and kill them if all other methods to keep them from eating steelhead fail (NMFS and WDFW, 1995). CONCLUSIONS We have been able to document only these and a few other cases of conflicting conservation needs resulting from management plans targeted toward individual species. It is possible that this low number stems from several factors: lack of knowledge of the networks of which threatened and endangered species are part; the fact that comparatively few species are currently listed and that recovery plans for even fewer have been formulated; and the inadvertent protection for other listed species under some current recovery plans. We expect, however, that the potential for such conflicts will rise as ecologies of listed species become better known, more recovery plans are formulated, and habitat for conserving endangered species becomes more constricted. The greatest potential for conflicts in protecting species and for management of individual species under current policies will arise in situations in which habitat reductions—especially extreme reductions—themselves are the causes of endangerment and the habitats of listed species are largely overlapping. Resolution of such conflicts will have to be made on a case by case basis. A process should be devised that will facilitate such resolutions using analyses of risk and recovery as outlined in Chapter 8. The most effective way to avoid conflicts resulting from individual management plans is to maintain large enough protected areas for listed species to allow the existence of mosaics of habitats and dynamic processes of change within these areas. In addition to and as part of this strategy, multispecies plans should be devised that ensure the maintenance of habitat mosaics and ecological networks. Habitat (in the broadest sense) thus plays a crucial role in protecting individual target species and, ultimately, in reducing the need for listing additional species. The Fish and Wildlife Service has prepared a number of packages list use the print version of this publication as the authoritative version for attribution.

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About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please CONSERVATION CONFLICTS BETWEEN SPECIES 121 ing multiple species in the same ecosystems, and it has agreed in a recent judicial settlement "to direct each region, where biologically appropriate, to use a multi-species, ecosystem approach to their listing responsibilities under the ESA" (settlement agreement, The Fund for Animals v. Lujan, Civ. No. 92-800, December 15, 1992). This is an important directive whose implementation and oversight warrant priority. Key questions should be addressed as the initiative moves forward: Are listing resources best deployed to advance the policy? To what degree have staff and consulting resources been arranged to optimize cooperative work across taxa? To what extent have the FWS and National Marine Fisheries Service made a special effort to identify widespread species presenting great potential for conflict, but also for conflict resolution? Finally, should the National Biological Service (NBS) be an important vehicle for ensuring that these questions can be answered in the affirmative? RECOMMENDATIONS Because of the interactions of plants and animals with other organisms in their environments, the most effective way to avoid conflicts resulting from individual management plans of co-occurring endangered species is to maintain large enough protected areas for listed species to ensure the presence of habitat mosaics and to allow for the dynamic processes of change that will inevitably occur within such areas. As part of this strategy, multispecies plans (e.g., habitat conservation plans; see Chapter 4) should be devised that ensure habitat mosaics and ecological networks are maintained. When the available habitat is insufficient to avoid conflicts, the analysis of options will have to be done separately for each situation. In most cases, long-term results are more important than short-term ones. In the example of Bachman's sparrow and the red-cockaded woodpecker (Box 6-3), both birds would benefit in the long term under the Forest Service's plan, despite short-term declines in the sparrow's population. Other considerations would be whic126h species is most likely to suffer irreversible harm if its needs are not fully addressed, the taxonomic level of the populations involved (e.g., a full species is probably more important than a distinct population segment), and ecological considerations (e.g., would the loss of one species have a greater effect on the ecosystem than the loss of the other?). REFERENCES Angelstam, P. 1992. Conservation of communities—The importance of edges, surroundings and landscape mosaic structure. Pp. 9-70 in Ecological Principles of Nature Conserva use the print version of this publication as the authoritative version for attribution.

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About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please CONSERVATION CONFLICTS BETWEEN SPECIES 122 tion: Applications in Temperate and Boreal Environments, L. Hansson, ed. New York: Elsevier Applied Science. Bonnot, P. 1928. Report on the seals and sea lions of California. Fish Bulletin 14. California Division of Fish and Game, Sacramento, Calif. Cooper, R., and T.H. Johnson. 1992. Trends in steelhead (Oncorhynchus mykiss) abundance in Washington and along the coast of North America. Washington Department of Wildlife Report 92-20. Dunning, J.B., and B.D. Watts. 1990. Regional differences in habitat occupancy by Bachman's sparrow. Auk 107:463-372. Fiedler, P.L., R.A. Laidy, R.D. Laven, N. Gershenz, and L. Saul. 1993. The contemporary paradigm in ecology and its implications for endangered species conservation . Endangered Species Update 10:7-12. Fletcher, K.W. 1990. Habitats Used, Abundance and Distribution of Mexican Spotted Owl (Strix occidentalis lucida) on National Forest System Lands. U.S. Department of Agriculture Forest Service, Southwest Region, Albuquerque, N.M. 55 pp. Fraker, M. 1994. California Sea Lions and Steelhead Trout at the Chittenden Locks, Seattle, Washington. Marine Mammal Commission, Washington, D.C. Franklin, J. F. 1993. Preserving biodiversity: Species, ecosystems, or landscapes. Ecol. Appl. 3:202-205. FWS (U.S. Fish and Wildlife Service). 1992. Measures to Improve the Protection of Chinook Salmon in the Sacramento/San Joaquin River Delta. WRINT-USFWS—7. Expert testimony of U.S. Fish and Wildlife Service on chinook salmon technical information for State Water Resources Control Board Water Rights Phase of the Bay/Delta Proceedings, July 6. Ganey, J.L., and R.P. Balda. 1989. Distribution and habitat use of Mexican spotted owls in Arizona. Condor 91:355-361. Ganey, J.L., J.A. Johnson, R.P. Balda, and R.W. Skaggs. 1988. Status report: Mexican spotted owl. Pp. 145-150 in Proceedings of the Southwest Raptor Management Symposium and Workshop, R.L. Glinski, B.G. Pendleton, M.B. Moss, M.N. LeFranc, Jr., B.A. Milsap, and S.W. Hoffman, eds. National Wildlife Federation, Washington, D.C. Gearin, P., R. Pfeifer, S.J.J. Jeffries, R.L. DeLong, and M.A. Johnson. 1988. Results of the 1986-1987 California Sea Lion-steelhead Trout Predation Control Program at the Hiram M. Chittenden Locks. Northwest and Alaska Fisheries Center Processed Report 88-30. Alaska Fisheries Science Center, Seattle, Wash. Holt, S.J., and L.M. Talbot. 1978. New principles for the conservation of wild living resources, Vol. 59. Wildlife Society, Louisville, Ky. Kolasa, J., and S.T.A. Pickett, eds. 1991. Ecological Heterogeneity. New York: Springer. Little, S. 1977. Wildflowers of the pine barrens and their niche requirements. N.J. Outdoors 1:16-18. Little, S. 1979. Fire and plant succession in the New Jersey pine barrens. Pp. 297-314 in Pine Barrens: Ecosystem and Landscape, R.T.T. Forman, ed. New York: Academic. Liu, J. 1992. ECOLECON: A Spatially Explicit Model for Ecological Economics of Species Conservation in Complex Forest Landscapes. PhD Dissertation. University of Georgia. Liu, J., F. Cubbage, and H.R. Pulliam. 1994. Ecological and economic effects of forest landscape structure and rotation length: Simulation studies using ECOLECON. Ecol. Econ. 10:249-263. Liu, J., J.B. Dunning, Jr., and H. Ronald Pulliam. 1995. Potential effects of a forest management plan on Bachman's Sparrows (Aimophila aestivalis): Linking a spatially explicit model with GIS. Conserv. Biol. 9(1):62-75. Marquis, D.A., T.J. Grisez, J.C. Bjorkbom, and B.A. Roach. 1975. Interim Guide to Regeneration of Alleghany Hardwoods. USDA Forest Service Gen. Tech. Rep. NE-19. U.S. use the print version of this publication as the authoritative version for attribution.

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About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please CONSERVATION CONFLICTS BETWEEN SPECIES 123 Department of Agriculture Forest Service, Northeastern Forest Experiment Station: Upper Darby, PA. McDonnell, M.J., and S.T.A. Pickett, eds. 1993. Humans as Components of Ecosystems: The Ecology of Subtle Human Effects and Populated Areas. New York: Springer. Merriam, C.H. 1901. Food of sea lions. Science N.S. 13:777-779. NMFS and WDWF (National Marine Fisheries Service and Washington Department of Fish and Wildlife). 1995. Environmental Assessment on Protecting Winter-Run Steelhead from Predation by California Sea Lions in the Lake Washington Ship Canal, Seattle, Wash. National Marine Fisheries Service Northwest Regional Office, Seattle, and Washington Department of Fish and Wildlife, Olympia. Olesiuk, P.F. 1993. Annual prey consumption by harbor seals (Phoca vitulina) in the Strait of Georgia, British Columbia. Fish. Bull. 91:491-515. Orians, G.H. 1993. Endangered at what level? Ecol. Appl. 3:206-208. Pickett, S.T.A., V.T. Parker, and P. Fiedler. 1992. The new paradigm in ecology: Implications for conservation biology above the species level. Pp. 65-88 in Conservation Biology: The Theory and Practice of Nature Conservation, Preservation, and Management, P. Fiedler and S. Jain, eds. New York: Chapman and Hall. Pickett, S.T.A., and P.S. White, eds. 1985. The Ecology of Natural Disturbance and Patch Dynamics. Orlando, Fla.: Academic. Pulliam, H.R., J.B. Dunning, and J. Liu. 1992. Population dynamics in complex landscapes: a case study. Ecol. Appl. 2:165-177. Reynolds, R.T., R.T. Graham, M. Hildegard, R.L. Bassett, P.L. Kennedy, D.A. Boyce, Jr., G. Goodwin, and E.L. Fisher. 1992. Management Recommendations for the Northern Goshawk in the Southwestern United States. Fort Collins, CO: Rocky Mountain Forest and Range Experiment Station; Albuquerque, NM: Southwestern Region, Forest Service, U.S. Department of Agriculture. USDA Gen. Tech. Rep. RM-217. 90 pp. Risser, P.G. 1985. Toward a holistic management perspective. BioScience 35:414-418. Saunders, D.A., R.J. Hobbs, and C.R. Margules. 1991. Biological consequences of ecosystem fragmentation: A review. Conserv. Biol. 5:18-32. Skaggs, R.W. 1990. Spotted owl telemetry studies in the Lincoln National Forest, Sacramento Division: Progress Report. New Mexico Department of Game and Fish, Santa Fe. 7 pp. Tyser, R.W., and C.A. Whorley. 1992. Alien flora in grasslands adjacent to road and trail corridors in Glacier National Park, Montana (USA). Conserv. Biol. 6:253-262. Walker, B. 1989. Diversity and stability in ecosystem conservation. Pp. 121-130 in Conservation for the Twenty-first Century, D. Western and M.C. Pearl, eds. New York: Oxford University Press. Willingham, W.F. 1992. Northwest Passages: A History of the Seattle District U.S. Army Corps of Engineers, 1896-1920. U.S. Army Corps of Engineers, Seattle District. use the print version of this publication as the authoritative version for attribution.