RESPONSES OF BREEDING REED WARBLERS ACROCEPHALUS-SCIRPACEUS TO MOUNTS OF SPARROWHAWK ACCIPITER-NISUS, CUCKOO CUCULUS-CANORUS AND JAY GARRULUS-GLANDARIUS
RESPONSES OF BREEDING REED WARBLERS ACROCEPHALUS-SCIRPACEUS TO MOUNTS OF SPARROWHAWK ACCIPITER-NISUS, CUCKOO CUCULUS-CANORUS AND JAY GARRULUS-GLANDARIUS
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DOI：
10.1111/j.1474-919x.1991.tb04812.x
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发表时间：
1991-01-01
期刊：
影响因子：
2.1
通讯作者：
DUCKWORTH, JW
中科院分区：
文献类型：
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作者：
DUCKWORTH, JW
在各繁殖阶段的芦苇林莺巢内，分别出现了一只杜鹃、一只雀鸟、一只雀鸟和一只野鸦。反应强度可以根据接近距离(到坐骑)和所使用的发声方式进行最佳分类。林莺对巢上的坐骑的反应比对邻近3米长的坐骑更具攻击性；它们靠近得更近，不太可能唱歌，但经常发出疯狂的沙沙声(这是从来不会给邻近的坐骑的)。他们对杜鹃的反应比对雀鹰的反应更具攻击性，因为杜鹃经常受到攻击，而他们对雀鸟的反应是中等的。离合器完成后的反应比以前更具攻击性。在杜鹃幼崽羽化后，父母们仍然对Jay和Sparrowhawk做出了强烈的回应，但只对杜鹃做出了短暂的回应，然后对其置之不理。这些结果与生殖价值-刺激价值假说是一致的。他们还证明，芦苇林莺和许多非寄主物种一样，可以区分杜鹃和雀鸟。这两个物种的相似之处经常被认为是杜鹃对雀鹰的模仿，但如果是这样的话，这是不成功的。或者，这种相似性可以是模仿，以减少对杜鹃本身的捕食，一种偶然的相似，或者由于作用于这两个物种的相似的选择性力量，因为每个物种都可能从减少的显眼程度中受益。
Mounts of a Cuckoo Cuculus canorus, a Sparrowhawk Accipiter nisus and a Jay Garrulus glandarius were presented at nests of Reed Warblers Acrocephalus scirpaceus at all breeding stages. Response strength could best be classified according to approach distance (to the mount) and vocalizations used. Warblers reacted much more aggressively to a mount on the nest than to one 3 m adjacent; they approached much more closely, were less likely to sing but often gave a frenzied-sounding rasp (which was never given to an adjacent mount). Reaction was more aggressive to a Cuckoo, which was often attacked, than to a Sparrowhawk, of which they were wary; response to a Jay was intermediate. Reaction was more aggressive after the clutch had been completed than before. After the brood had fledged, parents still responded strongly to the Jay and Sparrowhawk, but responded to the Cuckoo only briefly before ignoring it. These results are consistent with the Reproductive Value-Stimulus Value hypothesis. They also demonstrate that Reed Warblers can tell Cuckoos from Sparrowhawks, as can many non-host species. The close resemblance of these two species is often suggested to be mimicry of the Sparrowhawk by the Cuckoo but, if this is so, it is not successful. Alternatively, the similarity could be mimicry to reduce predation on the Cuckoos themselves, a chance resemblance, or due to similar selective forces acting on both species, as each would presumably benefit from reduced conspicuousness.