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Cattle egret: south to Tasmania and New Zealand for the winter | Notornis and Birds New Zealand
[摘要] The results of monitoring changes in Cattle Egret numbers in New Zealand and eastern Australia, recovery records for long-distance movements of marked birds from colonies in eastern Australia, and records for wing-tagged and colour-banded birds in the Hunter Valley of NSW indicate that a pattern of movement from the colonies occurs in waves in a south to south-easterly direction to Victoria, Tasmania and New Zealand during autumn and a return in spring. This movement can be described as migration. Although there is some circumstantial evidence, there is no confirmation that the same birds travel the same routes to the same destination each year. In the wintering areas they tend to restrict their activities to well-defined local territories. Significant numbers of birds remain in their natal area, however, where they may move relatively little, restricting foraging to a very limited local area for long periods, or be somewhat nomadic within a restricted region.
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[效力级别]  [学科分类] 动物科学
[关键词] NOTE: partial article only;pages missing from scanned issue. [时效性] 
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