Ecology and declining status of the silver-spotted skipper butterfly (Hesperia comma) in Britain
Ecology and declining status of the silver-spotted skipper butterfly (Hesperia comma) in Britain
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英国银斑船长蝴蝶（Hesperia comma）的生态和衰退状况
DOI：
10.2307/2404023
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发表时间：
1986
影响因子：
5.7
通讯作者：
R. Clarke
中科院分区：
文献类型：
--
作者：
Jeremy A. Thomas;C. Thomas;D. J. Simcox;R. Clarke
对所有的英国殖民地进行了调查，结果显示，它的种群数量已经减少到大约49个，其中大多数是小种群。(2)成虫在产卵时非常讲究。他们更喜欢小的羊茅植物，这些植物大部分被裸露的地面或砾石包围，也生长在遮阳的太阳黑子里。在大多数地点生长的大部分羊绒粉虱被视为不适合产卵而拒绝，成虫种群密度与草地接近理想产卵结构的程度有关。(3)大部分失去逗号的地点仍含有丰富的葡萄球菌，但由于过度生长而不适合繁殖。大多数麻豆的灭绝发生在20年的时间里，当时英国许多未受精的山间空地因兔子患粘液瘤病而死亡，杂草丛生。(4)自20世纪70年代末以来，由于兔子和一些羊在废弃的丘陵上放养的恢复，在几个以前的地点上，逗号的栖息地得到了改善。迄今为止，逗号只扩散到距离现有群落4公里以内的地方。其他地点的自然再定居可能需要几十年或几个世纪。自然资源保护主义者可以通过人工引进到无人居住的地方来显著改善红逗号的状况。现存的栖息地中有很大一部分已经在自然保护区，但由于放牧不足，到1982年，四分之一的“受保护”种群已经灭绝。
(1) A survey was made of all British colonies of Hesperia comma, which revealed that it had declined to about forty-nine populations, most of which were small. (2) Adult H. comma proved to be very particular when egg-laying. They preferred small Festuca ovina plants that were largely surrounded by bare ground or scree, and which also grew in sheltered sunspots. Most F. ovina growing on most sites were rejected as unsuitable, and the adult population density of H. comma was correlated with how closely the sward approached the ideal structure for egg-laying. (3) Most sites that had lost H. comma still contained abundant F. ovina, but were too overgrown to be suitable for breeding. Most extinctions of H. comma occurred during a twenty-year period, when many unfertilized downs in Britain became overgrown after rabbits were killed by myxomatosis. (4) The habitat on several former sites has improved for H. comma since the late 1970s, due to a recovery by rabbits and some sheep stocking on abandoned downs. To date, H. comma has only spread to re-occupy sites that were within 4 km of existing colonies. The natural recolonization of other sites may take decades or centuries. (5) Conservationists could dramatically improve the status of H. comma by making artificial introductions to unoccupied sites. A high proportion of the existing colonies are already on nature reserves, but one-quarter of 'protected' populations had become extinct by 1982, due to inadequate grazing.