United States and Canadian governments have responded to legal requirements to reduce human-induced whale mortality via vessel strikes and entanglement in fishing gear by implementing a suite of regulatory actions. We analyzed the spatial and temporal patterns of mortality of large whales in the Northwest Atlantic (23.5°N to 48.0°N), 1970 through 2009, in the context of management changes. We used a multinomial logistic model fitted by maximum likelihood to detect trends in cause-specific mortalities with time. We compared the number of human-caused mortalities with U.S. federally established levels of potential biological removal (i.e., species-specific sustainable human-caused mortality). From 1970 through 2009, 1762 mortalities (all known) and serious injuries (likely fatal) involved 8 species of large whales. We determined cause of death for 43% of all mortalities; of those, 67% (502) resulted from human interactions. Entanglement in fishing gear was the primary cause of death across all species (n = 323), followed by natural causes (n = 248) and vessel strikes (n = 171). Established sustainable levels of mortality were consistently exceeded in 2 species by up to 650%. Probabilities of entanglement and vessel-strike mortality increased significantly from 1990 through 2009. There was no significant change in the local intensity of all or vessel-strike mortalities before and after 2003, the year after which numerous mitigation efforts were enacted. So far, regulatory efforts have not reduced the lethal effects of human activities to large whales on a population-range basis, although we do not exclude the possibility of success of targeted measures for specific local habitats that were not within the resolution of our analyses. It is unclear how shortfalls in management design or compliance relate to our findings. Analyses such as the one we conducted are crucial in critically evaluating wildlife-management decisions. The results of these analyses can provide managers with direction for modifying regulated measures and can be applied globally to mortality-driven conservation issues.Evaluación del Manejo para Mitigar Efectos Antropogénicos sobre Ballenas MayoresResumenLos gobiernos de Estados Unidos y Canadá han respondido a requerimientos legales para reducir la mortalidad de ballenas inducida por humanos por medio de impacto con embarcaciones y enmarañamiento en artes de pesca mediante la implementación de un conjunto de acciones reguladoras. Analizamos los patrones espaciales y temporales de la mortalidad de ballenas mayores en el Atlántico Noroccidental (23.5°N a 48.0°N), de 1970 a 2009, en el contexto de cambios de manejo. Utilizamos un modelo logístico multinomial ajustado por la máxima probabilidad de detección de tendencias en mortalidades por causa específica en el tiempo. Comparamos el número de muertes provocadas por humanos con los niveles de remoción biológica potencial (i.e., mortalidad específica provocada por humanos sustentable). De 1970 a 2009, hubo 1762 muertes (conocidas) y lesiones se...

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A small, apparently isolated, and endangered population of~130 northern bottlenose whales (Hyperoodon ampullatus Forster, 1770) is found on the Scotian Slope south of Nova Scotia, Canada. Virtually all previous information on these animals had come from the Gully, a large submarine canyon where the northern bottlenose whales can be reliably found. A ship survey along the 1000 m depth contour in 2001 showed northern bottlenose whales only in the Gully, Shortland canyon (50 km east of the Gully), and Haldimand canyon (100 km east of the Gully). Studies in 2002 reconfirmed the presence of the whales in these other canyons, although densities were about 50% lower than in the Gully. Photo-identifications showed that individuals moved between the Gully and Shortland and Haldimand canyons over periods from days to years, with mean stays in any canyon of about 22 days. However, the population was not fully mixed: at least some individuals had preferences for particular canyons. The sex ratios were similar in all canyons, but males had higher rates of movement between canyons. These results are consistent with the expectations of optimal foraging theory, when the primary resource for females, deep-water squid of the genus Gonatus Gray, 1849, is more temporally stable than the primary resource for males, which is assumed to be receptive females. Haldimand and Shortland canyons are clearly important habitat for this species, and should receive appropriate protection.Résumé : Une petite population apparemment isolée et menacée de~130 baleines à bec communes (Hyperoodon ampullatus Forster, 1770) se retrouve sur le talus continental néo-écossais, au sud de la Nouvelle-Écosse, Canada. Presque toute l'information antérieure sur ces animaux provient de la région du Gully, un grand canyon sous-marin où les baleines à bec communes peuvent être trouvées régulièrement. Un inventaire en bateau le long du contour de 1000 m en 2001 a révélé la présence de baleines à bec communes seulement dans le Gully, dans le canyon Shortland (50 km à l'est du Gully) et dans le canyon Haldimand (100 km à l'est du Gully). Des études en 2002 confirment la présence des baleines dans les deux autres canyons, bien que les densités y soient d'environ 50 % plus basses que dans le Gully. Les identifications de baleines à l'aide de photographies indiquent que les individus se déplacent entre le Gully et les canyons Shortland et Haldimand sur des périodes variant de quelques jours à quelques années avec des durées moyennes de séjour dans un même canyon d'environ 22 jours. La population n'est cependant pas totalement intégrée et au moins quelques individus montrent une préférence pour un canyon en particulier. Le rapport mâles:femelles est semblable dans tous les canyons, mais les mâles ont un plus fort taux de déplacement d'un canyon à un autre. Ces résul-tats s'accordent avec les prédictions de la théorie de la quête optimale lorsque la ressource principale pour les femelles, les calmars d'eau profonde (genre Gonatus Gray, 1849), est plus stable dan...

To determine effectiveness of Seasonal Management Areas (SMAs), introduced in 2008 on the U.S. East Coast to reduce lethal vessel strikes to North Atlantic right whales, we analyzed observed large whale mortality events from 1990-2012 in the geographic region of the "Ship Strike Rule" to identify changes in frequency, spatial distribution, and spatiotemporal interaction since implementation. Though not directly coincident with SMA implementation, right whale vessel-strike mortalities significantly declined from 2.0 (2000)(2001)(2002)(2003)(2004)(2005)(2006) to 0.33 per year (2007)(2008)(2009)(2010)(2011)(2012). Large whale vessel-strike mortalities have decreased inside active SMAs, and increased outside inactive SMAs. We detected no significant spatiotemporal interaction in the 4-year pre-or post-Rule periods, although a longer time series is needed to detect these changes. As designed, SMAs encompass only 36% of historical right whale vessel-strike mortalities, and 32% are outside managed space but within managed timeframes. We suggest increasing spatial coverage to improve the Rule's effectiveness.