Lövei Gábor L, Ferrante Marco
Department of Agroecology, Flakkebjerg Research Centre, Aarhus University, Forsøgsvej 1, DK-4200 Slagelse, Denmark.
Insect Sci. 2017 Aug;24(4):528-542. doi: 10.1111/1744-7917.12405. Epub 2017 Jan 3.
Sentinel prey can provide a direct, quantitative measure of predation under field conditions. Live sentinel prey provides more realistic data but rarely allows the partitioning of the total predation pressure; artificial prey is less natural but traces left by different predators are identifiable, making it suitable for comparative studies. We reviewed the available evidence of the use of both types of invertebrate sentinel prey. Fifty-seven papers used real prey, usually measuring predation on a focal (often pest) species, with studies overwhelmingly from North America. The median predation was 25.8% d . Artificial sentinel prey (45 papers) were used in both temperate and tropical areas, placed more above ground than at ground level. The most commonly used artificial prey imitated a caterpillar. Up to 14 predator groups were identified, registering a median of 8.8% d predation; half the studies reported only bird predation. Predation on real prey was higher than on artificial ones, but invertebrate predation was not higher than vertebrate predation. Invertertebrate but not vertebrate predation was negatively related to prey size. Predation near the Equator was not higher than at higher latitudes, nor in cultivated than noncultivated habitats. The use of sentinel prey is not yet standardised in terms of prey size, arrangement, exposure period or data reporting. Due to the simplicity and ease of use of the method, such standardisation may increase the usefulness of comparative studies, contributing to the understanding of the importance and level of predation in various habitats worldwide.
在野外条件下，哨兵猎物可以提供捕食的直接定量测量。活体哨兵猎物能提供更现实的数据，但很少能区分总捕食压力；人工猎物不太自然，但不同捕食者留下的痕迹是可识别的，这使其适用于比较研究。我们回顾了使用这两种无脊椎动物哨兵猎物的现有证据。57篇论文使用了真实猎物，通常测量对一个重点（通常是害虫）物种的捕食情况，研究大多来自北美。捕食中位数为每日25.8%。人工哨兵猎物（45篇论文）在温带和热带地区都有使用，放置在地面以上的比在地面水平的更多。最常用的人工猎物模仿毛虫。最多识别出14个捕食者群体，记录的捕食中位数为每日8.8%；一半的研究仅报告了鸟类捕食。对真实猎物的捕食高于对人工猎物的捕食，但无脊椎动物的捕食并不高于脊椎动物的捕食。无脊椎动物而非脊椎动物的捕食与猎物大小呈负相关。赤道附近的捕食并不高于高纬度地区，在耕种栖息地的捕食也不高于未耕种栖息地。在猎物大小、布置、暴露期或数据报告方面，哨兵猎物的使用尚未标准化。由于该方法简单易用，这种标准化可能会提高比较研究的有用性，有助于理解全球各种栖息地中捕食的重要性和水平。
