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Lethal control, which has been used to reduce local abundances of animals in conflict with humans or with endangered species, may not achieve management goals if animal movement is not considered. In populations with emigration and immigration, lethal control may induce compensatory immigration, if the source of attraction remains unchanged. Within the Columbia River Basin (Washington, U.S.A.), avian preda- tors forage at dams because dams tend to reduce rates of emigration of juvenile salmonids (Oncorhynchus spp.), artificially concentrating these prey. We used differences in fatty acid profiles between Caspian Terns (Hydroprogne caspia) at coastal and inland breeding colonies and terns culled by a lethal control program at a mid-Columbia River dam to infer dispersal patterns. We modeled the rate of loss of fatty acid biomarkers, which are fatty acids that can be traced to a single prey species or groups of species, to infer whether and when terns foraging at dams had emigrated from the coast. Nonmetric multidimensional scaling showed that coastal terns had high levels of C20 and C22 monounsaturated fatty acids, whereas fatty acids of inland breeders were high in C18:3n3, C20:4n6, and C22:5n3. Models of the rate of loss of fatty acid showed that approximately 60% of the terns collected at Rock Island Dam were unlikely to have bred successfully at local (inland) sites, suggesting that terns foraging at dams come from an extensive area. Fatty acid biomarkers may provide accurate information about patterns of dispersal in animal populations and may be extremely valuable in cases where populations differ demonstrably in prey base.

Since its founding in 1863, the National Academy of Sciences (NAS) has occupied a special niche in the complex ecology of advice-giving in the United States. Established as a small, private organization with special responsibilities and obligations vis a vis the American people and government, the Academy has expanded considerably in the past century and a half and now releases, through the National Research Council (NRC), its operating arm, more than 200 reports per year, on topics covering nearly the entire range of science, engineering, health, and education. The development of the organization, its basic ethos, and its evolving structures and processes can be seen as examples of what Herbert Simon called “procedural rationality”: the pursuit of reasonably good solutions to complex problems based on appropriate deliberation.

Heritability of flowering and leafing date of pistachio (Pistacia vera L.) were estimated based on half-sib family and parent-offspring regression analyses. Narrow sense heritabilities of flowering date ranged from 0.68 to 0.88 based on half-sib analyses and from 0.89 to 0.95 based on parent-offspring regression analyses. The narrow sense heritability of leafing date was 0.75 based on half-sib analyses and 0.60 from parent-offspring regression analysis. First leafing date was highly correlated with flowering date (r =0.59–0.78), suggesting that first leafing date could be used to select for flowering date in seedlings long before the onset off lowering.

Predator-prey relationships are often altered as a result of human activities. Where prey are legally protected, conservation action may include lethal predator control. In the Columbia River basin (Pacific Northwest, USA and Canada), piscivorous predators have been implicated in contributing to a lack of recovery of several endangered anadromous salmonids (Oncorhynchus spp.), and lethal and nonlethal control programs have been instituted against both piscine and avian species. To determine the consequences of avian predation, we used a bioenergetics approach to estimate the consumption of salmonid smolts by waterbirds (Common Merganser, California and Ring-billed Gull, Caspian Tern, Double- crested Cormorant) found in the mid-Columbia River from April through August, 2002-2004. We used our model to explore several predator-prey scenarios, including the impact of historical bird abundance, and the effect of preserving vs. removing birds, on smolt abundance. Each year, ,1% of the estimated available salmonid smolts (interannual range: 44 830-109 209; 95% CI ¼ 38 000-137 000) were consumed, 85-98% away from dams. Current diet data combined with historical gull abundance at dams suggests that past smolt consumption may have been 1.5-3 times current numbers, depending on the assumed distribution of gulls along the reaches. After the majority (80%) of salmonid smolts have left the study area, birds switch their diet to predominantly juvenile northern pikeminnow (Ptychocheilus oregonensis), which as adults are significant native salmonid predators in the Columbia River. Our models suggest that one consequence of removing birds from the system may be increased pikeminnow abundance, which—even assuming 80% compensatory mortality in juvenile pikeminnow survival—would theoretically result in an annual average savings of just over 180 000 smolts, calculated over a decade. Practically, this suggests that smolt survival could be maximized by deterring birds from the river when smolts are present, allowing bird presence after the diet switch to act as a tool for salmonid-predator control, and conducting adult-pikeminnow control throughout. Our analysis demonstrates that identifying the strength of ecosystem interactions represents a top priority when attempting to manage the abundance of a particular ecosystem constituent, and that the consequences of a single-species view may be counterintuitive, and potentially counterproductive.