The migratory destinations of humpback whales that feed off California. Oregon and Washington wer... more The migratory destinations of humpback whales that feed off California. Oregon and Washington were determined using photo-identification. Fluke photographs of 594 individuals were taken between 1981 and 1992 and compared to collections from 9 wintering regions in the North Pacific: Ogasawara (162) and Okinawa (17) islands of Japan; the Big Island and Maui (634 for both) and Kauai (384) of Hawaii; the Revillagigedo Archipelago (450), the mainland coast (383) and Baja Peninsula (471) of Mexico; and Central America (31). A total of 160 matches were found to 6 central and eastern North Paclfic wintering regions, with most from Central America, Baja, and mainland Mexico. Of whales identified off Central America, 84 % were resighted off California-Washington, this high rate of interchange suggests that whales in these tropical waters appear to be comprised entirely of animals from the California-Washington feeding aggregation. Humpback whales seen off Central America were reslghted disproportionately off southern California while those from mainland ~Vexico tended to be seen off northern California-Washington. From 157 same-season migratory transits documented, the shortest were 29 d to Baja and 56 d to Costa Rica and the longest distance was 5322 km. Of the Cal-ifornia-Washington whales with known sex, the proportion of males identified at a wintering region was significantly higher than females (2.2:1, p < 0.05).
... We thank R Emmett, B Hanson, J Estes, and three anon-ymous reviewers for providing critiques ... more ... We thank R Emmett, B Hanson, J Estes, and three anon-ymous reviewers for providing critiques of the man-uscript. C Wilson at the Northwest Fisheries Science Center provided critical library services to our re-mote field site. ...
Summary The endangered southern resident population of killer whales has been shown to be food li... more Summary The endangered southern resident population of killer whales has been shown to be food limited, and the reduced availability of their primary prey, chinook salmon, has been identified as a key threat to population viability. Our study aimed to collect aerial ...
The humpback whale (Megaptera novaeangliae) is a cosmo- politan species whose stocks were dras- t... more The humpback whale (Megaptera novaeangliae) is a cosmo- politan species whose stocks were dras- tically decreased by commercial whal- ing practices prior to 1967. The North Pacific population was estimated to be between 15,000 and 20,000 animals before the practice of whaling. At the time of the commencement of its inter- national protection in 1967, this popu- lation may have
The migratory destinations of humpback whales that feed off California. Oregon and Washington wer... more The migratory destinations of humpback whales that feed off California. Oregon and Washington were determined using photo-identification. Fluke photographs of 594 individuals were taken between 1981 and 1992 and compared to collections from 9 wintering regions in the North Pacific: Ogasawara (162) and Okinawa (17) islands of Japan; the Big Island and Maui (634 for both) and Kauai (384) of Hawaii; the Revillagigedo Archipelago (450), the mainland coast (383) and Baja Peninsula (471) of Mexico; and Central America (31). A total of 160 matches were found to 6 central and eastern North Paclfic wintering regions, with most from Central America, Baja, and mainland Mexico. Of whales identified off Central America, 84 % were resighted off California-Washington, this high rate of interchange suggests that whales in these tropical waters appear to be comprised entirely of animals from the California-Washington feeding aggregation. Humpback whales seen off Central America were reslghted disproportionately off southern California while those from mainland ~Vexico tended to be seen off northern California-Washington. From 157 same-season migratory transits documented, the shortest were 29 d to Baja and 56 d to Costa Rica and the longest distance was 5322 km. Of the Cal-ifornia-Washington whales with known sex, the proportion of males identified at a wintering region was significantly higher than females (2.2:1, p < 0.05).
... We thank R Emmett, B Hanson, J Estes, and three anon-ymous reviewers for providing critiques ... more ... We thank R Emmett, B Hanson, J Estes, and three anon-ymous reviewers for providing critiques of the man-uscript. C Wilson at the Northwest Fisheries Science Center provided critical library services to our re-mote field site. ...
Summary The endangered southern resident population of killer whales has been shown to be food li... more Summary The endangered southern resident population of killer whales has been shown to be food limited, and the reduced availability of their primary prey, chinook salmon, has been identified as a key threat to population viability. Our study aimed to collect aerial ...
The humpback whale (Megaptera novaeangliae) is a cosmo- politan species whose stocks were dras- t... more The humpback whale (Megaptera novaeangliae) is a cosmo- politan species whose stocks were dras- tically decreased by commercial whal- ing practices prior to 1967. The North Pacific population was estimated to be between 15,000 and 20,000 animals before the practice of whaling. At the time of the commencement of its inter- national protection in 1967, this popu- lation may have
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