ABSTRACT Predation by introduced mammals frequently limits abundance of New Zealand’s native invertebrates. We investigated responses of beetle and wētā communities to mammal eradication at two fenced forest sites at Maungatautari. Ground-dwelling beetle abundance, but not species richness, increased inside the southern exclosure two years after all mammals were eradicated. In the next 5 years, when all mammals except mice were eradicated from all of Maungatautari, beetle abundance and species richness were frequently higher in the mouse-free southern exclosure. Beetle community composition changed after mammal eradication, and over time with increasing mice densities outside the southern exclosure. Large, predatory, and native beetles showed the most differences between inside and outside the southern exclosure over some years. Wētā were more responsive to mammal removal than beetles. Wētā abundances both inside and outside the southern exclosure were similar when most mammals were eradicated and mice were controlled to low numbers. However, wētā declined in the following 2 years outside the southern exclosure when mouse abundance increased. Abiotic and biotic factors affecting the beetle and wētā communities are complex and interactions poorly understood. This study indicates that climate and predation by native fauna are likely to be important factors.

中文翻译：

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甲虫和 wētā 社区对新西兰怀卡托 Maungatautari 哺乳动物灭绝的反应

摘要 引入哺乳动物的捕食经常限制新西兰本土无脊椎动物的数量。我们在 Maungatautari 的两个围栏森林地点调查了甲虫和 wētā 群落对消灭哺乳动物的反应。在所有哺乳动物被根除两年后，地栖甲虫的数量增加了，但物种丰富度却没有增加。在接下来的 5 年中，当所有 Maungatautari 中除小鼠以外的所有哺乳动物都被根除时，没有老鼠的南部围栏的甲虫丰度和物种丰富度往往更高。哺乳动物灭绝后，甲虫群落组成发生了变化，并且随着时间的推移，南部围栏外的小鼠密度增加。多年来，大型、掠食性和本地甲虫在南部围栏内外表现出最大的差异。Wētā 对哺乳动物的移除比甲虫更敏感。当大多数哺乳动物被消灭并且老鼠被控制在低数量时，南部围栏内外的 Wētā 丰度相似。然而，当小鼠丰度增加时，wētā 在接下来的 2 年中在南部围栏外下降。影响甲虫和 wētā 群落的非生物和生物因素很复杂，相互作用知之甚少。这项研究表明，气候和本地动物的捕食可能是重要的因素。影响甲虫和 wētā 群落的非生物和生物因素很复杂，相互作用知之甚少。这项研究表明，气候和本地动物的捕食可能是重要的因素。影响甲虫和 wētā 群落的非生物和生物因素很复杂，相互作用知之甚少。这项研究表明，气候和本地动物的捕食可能是重要的因素。