During the 42 years from 1975 to 2018 (except for 1996 and 1997), 8,054 Great Cormorants (Phalacrocorax carbo) were banded in six colonies in Southern Kanto. By June 2019, 430 banded individuals had been recovered, including 50 that were confirmed dead in the natal colony. The number of "removals" (shot and killed) was four individuals banded in the first period (1975–1995) compared to 81, most of which were between 0 and 1 year old, banded in the second period (1998–2018). There were no "caught in net" recoveries in the first period; in the second period, 25 individuals were mostly under a year old. The average number of survival days of the recovered, "removed" birds in the second period was longer than those with other causes of death, as many other individuals died under a year old. In addition, the average distance between the natal colony and the recovery locations was longer in the second period than in the first period when compared (excluding recovered individuals in the natal colony). This is because a greater number of colonies and roosts were established around Southern Kanto, a larger area, in the second half of this period. These recovery records indicate a significant influence of habitat status in the study area and appreciable age differences in cormorants in certain cases of recovery.
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