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Cover: Recreational fishers can be instrumental in successful fisheries conservation projects, thereby reducing fisheries declines. In Mongolia's Eg‐Ur watershed, recreational anglers, local citizens, and scientists have teamed up to protect the world's largest salmonid, Hucho taimen. Photo by Sudeep Chandra. See pages 1125–1134.  相似文献   

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Cover: A poster of the Ivory‐billed Woodpecker (Campephilus principalis) decorates the wall of a restaurant in Brinkley, Arkansas (U.S.A.). The town is located near where the bird was reportedly sighted in 2004, 60 years after its presumed extinction. Th ree papers in this issue present new methods to estimate whether species are extinct. On pages 47‐56, Gotelli et al. introduce a statistical method for estimating the probability of species persistence from the temporal sequence of collection dates of museum specimens. Application of the method to a case study of the Ivory‐billed Woodpecker suggests there is virtually no chance the species is currently extant within its historical range in the southeastern United States. On pages 180‐184, Solow et al. describe a Bayesian method that formally accounts for species records of uncertain validity. They used a recently published record of sightings of the Ivory‐billed Woodpecker to illustrate their method. Their results were consistent with the conclusion that the species is extinct, but did not provide a clear estimate of the time of extinction. On pages 57‐67, Fisher and Blomberg outline how to estimate the probability that species with few records or recent last‐sighting dates are extinct. Cover image © 2012 Joel Sartore. Photographer: During more than 20 years with the National Geographic Society, Joel Sartore ( http://www.joelsartore.com ) has covered topics from the Amazon rainforest to beer‐drinking, mountain‐racing. firefighters in the United Kingdom. His work focuses on endangered species, natural history, and land use. Joel's books include Photographing Your Family, Face to Face with Grizzlies, Nebraska: Under a Big Red Sky, RARE: Portraits of America's Endangered Species, and, most recently, Let's Be Reasonable. In addition to his work for National Geographic, Joel has completed assignments for Audubon Magazine, Time, Life, Newsweek, and Sports Illustrated and has contributed to numerous book projects. Joel and his work have been the subject of several national broadcasts in the United States, including National Geographic's Explorer, NBC Nightly News, NPR's Weekend Edition, and an hour‐long PBS documentary. He is a regular contributor to the CBS Sunday Morning Show.  相似文献   

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Cover: Hunting of endangered species, especially large primates, by Matsigenka indigenous people living in Manu National Park, Peru, has prompted debate over whether indigenous populations living in tropical parks have the potential to be conservation partners or should be treated as threats to biodiversity conservation. Participatory monitoring of hunting in the park showed that even after decades of subsistence hunting and localized depletion, large primates and other vulnerable species continue to be hunted at high rates, indicating source-sink dynamics and suggesting that there is time to devise a co-management plan. See pages 1174–1185. Photos by Glenn Shepard Jr. (top) and Julia Ohl (bottom).  相似文献   

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Cover : A local boy spearfishing in Wakatobi Marine National Park, Sulawesi, Indonesia, 2004. Octopus, grouper, fusilier, and scorpionfish commonly are fished in the area. Customary management systems that limit fishing can increase the biomass of fishes targeted by local fishers. Feary et al. (pp. 341‐349) found that customary closures affect the distance at which a fish begins to flee an approaching threat. This flight distance, in turn, can influence local fishing success. However, the accuracy of conventional techniques used by scientists for censusing reef fishes do not appear to be affected by changes in flight behavior associated with fishing.  相似文献   

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Cover: Tropical pastures present multiple barriers to tree regeneration, but canopies of relict trees can serve as repositories of viable seeds deposited when the forest was intact. When mats of arboreal soil fall to the pasture floor, their seedbank can contribute to forest regeneration, their seeds serving as "time capsules" from the primary forest. The lush epiphytic ferns ( Polypodium spp. ) and accompanying arboreal soil on this mature live oak are viewed from above in a subtropical landscape of Florida. Photo by John T. Longino. See pages 1117–1126.  相似文献   

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Cover: Tree pincushion (Leucospermum conocarpodendron viridum), a member of the family Proteaceae and the largest member of its genus, Cape of Good Hope National Park, South Africa. On pages 593‐601, Tucker et al. explore differences in the species richness, phylogenetic diversity, and evolutionary distinctiveness of Proteaceae species in the Cape Floristic Region of South Africa. They found that species richness and phylogenetic diversity typically were highly correlated, but sites with high phylogenetic diversity were more spatially extensive than sites with high species richness. Rare species generally had high levels of evolutionary distinctiveness. Sites near the southern edge of the Cape Floristic Region were occupied by species with high levels of evolutionary distinctiveness and limited geographic ranges, but those sites were not assigned high conservation‐priority rankings on the basis of species richness or phylogenetic distinctiveness. Photographer: Photographer and conservationist Jaime Rojo ( http://www.jaime‐rojo.com ) believes visual storytelling is a powerful tool for conservation. Since moving to Mexico from his native Spain 8 years ago, Jaime has worked with diverse environmental nongovernmental organizations while developing his career as a photographer. He has participated in numerous conservation initiatives including the promotion of El Carmen Big Bend Conservation Corridor, a transboundary protected area along the border between Mexico and the United States; a campaign to protect the San Pedro Mezquital, the last free‐flowing river in the western Sierra Madre; and the celebration of WILD9, the ninth World Wilderness Congress, for which he was executive director in Mexico. Rojo is a trustee of Th e WILD Foundation and an associate of the International League of Conservation Photographers.  相似文献   

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Cover: A Tibetan sacred landscape (Mt. Kawagebo), with Tibetan prayer flags in the foreground. Public protected areas in China can conflict with traditional land uses and disenfranchise local people, who have long-term experience in land management. Development of cooperative relationships between the state and local communities is needed for community-driven conservation strategies. Photo by Xu Jianchu. See pages 318–328.  相似文献   

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Cover : Farming of tigers (Panthera tigris) has been proposed as a disincentive to illegal trade that is decreasing the abundance and distribution of tigers in the wild. In this issue, Kirkpatrick and Emerton (pp. 655–659) examine the economic rationale for tiger farming. In theory, the pro. tability of poaching will decrease as availability of tigers increases. Given the consumer preference for wild tigers and price controls by traders, however, farming actually may increase demand for wild tigers and lead to a greater incidence of poaching.  相似文献   

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