RESUMEN: Las poblaciones de la lamprea del Pacífico (Entosphenus tridentatus) están declinando en la cuenca del Río Columbia, y desde el año 2000 se ha implementado la translocación de individuos adultos para restablecer los corredores migratorios de esta especie. Se describen y reportan los resultados de dos programas recientes de translocación, se contextualiza el uso de la translocación y se discuten sus beneficios potenciales, riesgos e incertidumbre. Ambos programas de translocación parecen haber incrementado el número de adultos desovantes y la presencia tanto de larvas como de juveniles; sin embargo, para que sea posible cualquier incremento ulterior en el stock natural de reproductores se requerirá de al menos una, aunque muy probablemente de más, generaciones. Se observó que el número de adultos que ingresó al Río Umatilla aumentó en los primeros cuatro años después de la primera translocación. Los beneficios potenciales de los programas de translocación son un aumento en la producción de feromonas por parte de larvas ammocoetes para atraer adultos, incremento en la distribución y abundancia de lampreas en áreas objetivas, incremento en la cantidad de nutrientes derivados del medio marino y la promoción de culturas tribales. Los riesgos potenciales incluyen modificación de la estructura poblacional y las adaptaciones genéticas asociadas, transmisión de enfermedades y agotamiento de los stocks donadores. ABSTRACT: The Pacific lamprey (Entosphenus tridentatus) is in decline in the Columbia River Basin, and translocating adult lamprey to bypass difficult migration corridors has beenimplemented since 2000. We describe and report results from two current translocation programs, provide context for use of translocation, and discuss potential benefits, risks, and uncertainties. Both translocation programs appear to have increased the number of spawning adults and the presence of larvae and juveniles; however, any subsequent increase in naturally spawning adults will require at least one, and likely more, generations to be realized. It was seen that the number of adults entering the Umatilla River increased beginning four years after the first translocations. Potential benefits of translocation programs are increased pheromone production by ammocoetes to attract adults, increased lamprey distribution and abundance in target areas, increased marine-derived nutrients, and promotion of tribal culture. Potential risks include disruption of population structure and associated genetic adaptations, disease transmission, and depletion of donor stocks.

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Numbers of American woodcock (Scolopax minor) males counted on the annual singing ground survey (SGS) have declined over the last 35 years at an average rate of 2.3% per year in the Eastern Region and 1.8% per year in the Central Region. Although hunting was not thought to be a cause of these declines, mortality caused by hunters can be controlled. Furthermore, there has been no research on effects of hunting mortality on woodcock populations at local and regional levels on the breeding grounds. We used radiotelemetry to determine survival rates and causes of mortality for 913 woodcock captured during fall 1997-2000 on 7 areas in Maine, New Hampshire, Pennsylvania, and Vermont, USA. Three of 7 sites were closed to hunting. For all sites and all years combined, 176 woodcock died, and 130 were censored, of which 39 were censored mortalities. Predation was the major (n = 134, 76%) cause of mortality. Mammals accounted for 56% of the predation, raptors accounted for 25%, and 19% was attributed to unknown predators. On hunted sites, 36% of the total mortality (n = 102) was caused by hunting, 63% by predation, and 1 bird starved. Kaplan-Meier survival curves did not differ between hunted and nonhunted sites among years (P = 0.46). Overall, point estimates of survival did not differ (P = 0.217) between hunted (SR = 0.636, SE = 0.04) and nonhunted sites (SR = 0.661, SE = 0.08). We modeled hazard rates from hunting and natural mortality events using program MARK. Akaike's Information Criterion supported using a model with common constant hazards from both hunting and natural causes for groups of sites. Groupings of sites for hazard rates from natural causes were not influenced by whether a site was hunted or not. Models detected no effects of woodcock age and sex (P = 0.52) on survival. Proportional hazards models comparing hunted and nonhunted sites found no effects of age and sex (P = 0.45), interactions of age, sex, capture weight, and bill length (P ≥ 0.269). Our data suggest that current hunting regulations are not causing lower survival of woodcock. JOURNAL OF WILDLIFE MANAGEMENT 69(4):1565-1577; 2005

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Predation by bobcats (Lynx rufus) is the major cause of mortality in captivereared whooping cranes (Grus americana) released into the wild to establish a nonmigratory flock in Florida. This study investigated whether rearing methods (parent-rearing, hand-rearing, or hand-rearing with exercise) of cranes, and behaviors observed in birds either before or shortly after release in the wild, are associated with survival after release. Rearing methods did not affect survival first year post-release, which was 55 78% in 2 yr (1999 and 2000). Logistic regression revealed, however, that foraging bouts (1), walking bouts (À), and body weight (À) before release, and nonvigilant bouts (À) after release were significantly associated with survival. These results suggest that post-release survival of whooping cranes might be increased by rearing techniques that promote foraging.