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This first quantitative study of the diet of Emperor penguins is based on 29 stomach contents collected with a water off-loading method in Adelie Land. The Emperor is largely ichthyophagous (65% by number and 95% by weight) and feeds extensively on small nototheniids (97% of the fish are 40–125 mm in overall length). These results and data on meal size and feeding frequency of the chick suggest that Emperors are off-shore foraging birds offering little competition for food with other sea-birds or mammals. 相似文献
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SCHIZOPTERID BUGS (INSECTA: HETEROPTERA) IN MID-CRETACEOUS AMBERS FROM FRANCE and MYANMAR (BURMA) 总被引:1,自引:0,他引:1
Abstract: Bugs of two new genera and species are described as Buzinia couillardi and Tanaia burmitica . They are preserved in mid-Cretaceous amber from south-west France and northern Myanmar (Burma), respectively ( c . 100 Ma). These are the first formally described fossils of the heteropteran family Schizopteridae. Both belong to the subfamily Hypselosomatinae and are very similar to the extant genus Hypselosoma Reuter, providing evidence for the antiquity and morphological stability of this small bug family and the infraorder Dipsocoromorpha. Given the putative ecology of the fossils, a discussion is provided on the French and Burmese amber forest ecosystems. The geological setting of La Buzinie, a new amber deposit in south-west France that yielded the two specimens of Buzinia couillardi , is outlined. 相似文献
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VINCENT NIJMAN 《Ibis》2001,143(1):99-106
The migration of four northern migrant raptors (Oriental Honey-buzzard Pernis ptilorhyncus , Chinese Sparrowhawk Accipiter soloensis, Japanese Sparrowhawk A. gularis and Common Buzzard Buteo buteo ) was studied in the Dieng mountains, Central Java, Indonesia during September-October 1998. Populations migrating through Central Java originate from northern Asia and most likely have passed over the Thai-Malay peninsula and Sumatra before reaching West and Central Java. An unknown proportion continues on to Bali and/or the Lesser Sunda Islands. In all, 68 groups totalling 885 individuals were counted passing by. Ninety-five percent of individuals identified were accipiters, two-thirds of which could be identified to the species level. Passage was directed from WSW-SW to E-ESE, following the alignment of volcanoes on the island. The number of groups was highest during late morning; single individuals were observed significantly more often during the early morning and large (> 25 individuals) groups during the afternoon. Single individuals and small (five or fewer individuals) groups spent significantly less time in the area than large groups. The forests of the Dieng mountains are also used as an overnight stopover and hunting site. Differences in the proportion of the two species of Accipiter identified at Javan and Bali study sites suggests an additional migration route to the one following the Javan mountains. This may follow the eastern edge of the Sunda Shelf. The Dieng mountains qualify as a globally Important Bird Area (IBA) on the grounds of the raptor congregations, as well as because of the presence of globally threatened and restricted range species. 相似文献