While habitat loss is a major threat to species, the effects of habitat fragmentation independent of habitat loss (fragmentation per se) are debated. Metapopulation studies often assert negative fragmentation effects, but they do not measure fragmentation per se. We evaluate the effects of fragmentation per se (patch density) across 20 years of patch occupancy patterns of the Åland Islands Glanville fritillary butterfly, Finland, a famous model system in metapopulation studies. Fragmentation per se had mainly positive effects on patch occupancy, the proportion of years occupied per patch, and patch colonization, and negative effects on patch extinction. These results suggest that fragmentation per se does not threaten persistence of the Åland Islands Glanville fritillary butterfly. Our results support the growing body of research challenging the paradigm that habitat fragmentation per se is mostly negative for species, highlighting the value of small patches for species conservation.

中文翻译：

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碎片化本身对最具标志性的集合种群产生积极影响

虽然栖息地丧失是对物种的主要威胁，但与栖息地丧失无关的栖息地破碎化（破碎化本身）的影响仍存在争议。集合种群研究经常断言负面的碎片化效应，但它们并不测量碎片化本身。我们评估了芬兰奥兰群岛格兰维尔贝母蝴蝶 20 年斑块占据模式中碎片本身（斑块密度）的影响，这是一个著名的复合种群研究模型系统。破碎化本身主要对斑块占有率、每个斑块占据的年数比例以及斑块殖民化产生积极影响，而对斑块灭绝产生负面影响。这些结果表明，碎片本身并不威胁奥兰群岛格兰维尔贝母蝴蝶的持续存在。我们的研究结果支持了越来越多的研究挑战栖息地破碎化本身对物种大多不利的范式，强调了小斑块对于物种保护的价值。