School of Life and Environmental Science, University of Sydney, Sydney, New South Wales, 2006, Australia.
School of Environmental and Forest Sciences, University of Washington, College of the Environment, Box 352100, Seattle, WA, 98195-2100, USA.
Biol Rev Camb Philos Soc. 2024 Apr;99(2):562-581. doi: 10.1111/brv.13035. Epub 2023 Dec 26.
Carrion acts as a hotspot of animal activity within many ecosystems globally, attracting scavengers that rely on this food source. However, many scavengers are invasive species whose impacts on scavenging food webs and ecosystem processes linked to decomposition are poorly understood. Here, we use Australia as a case study to review the extent of scavenging by invasive species that have colonised the continent since European settlement, identify the factors that influence their use of carcasses, and highlight the lesser-known ecological effects of invasive scavengers. From 44 published studies we identified six invasive species from 48 vertebrates and four main groups of arthropods (beetles, flies, ants and wasps) that scavenge. Invasive red foxes (Vulpes vulpes), domestic dogs (Canis familiaris), feral pigs (Sus scrofa), black rats (Rattus rattus) and feral cats (Felis catus) were ranked as highly common vertebrate scavengers. Invasive European wasps (Vespula germanica) are also common scavengers where they occur. We found that the diversity of native vertebrate scavengers is lower when the proportion of invasive scavengers is higher. We highlight that the presence of large (apex) native vertebrate scavengers can decrease rates of scavenging by invasive species, but that invasive scavengers can monopolise carcass resources, outcompete native scavengers, predate other species around carcass resources and even facilitate invasion meltdowns that affect other species and ecological processes including altered decomposition rates and nutrient cycling. Such effects are likely to be widespread where invasive scavengers occur and suggest a need to determine whether excessive or readily available carcass loads are facilitating or exacerbating the impacts of invasive species on ecosystems globally.
腐肉在全球许多生态系统中充当动物活动热点，吸引了依赖这种食物来源的食腐动物。然而，许多食腐动物是入侵物种，它们对食腐动物网络和与分解有关的生态系统过程的影响尚未得到充分了解。在这里，我们以澳大利亚为例，回顾自欧洲殖民以来，入侵物种在该大陆上的食腐程度，确定影响它们利用尸体的因素，并强调鲜为人知的入侵食腐动物的生态影响。从 44 项已发表的研究中，我们确定了 6 种来自 48 种脊椎动物和 4 种主要节肢动物（甲虫、苍蝇、蚂蚁和黄蜂）的入侵物种。入侵的红狐（ Vulpes vulpes ）、家犬（ Canis familiaris ）、野猪（ Sus scrofa ）、黑鼠（ Rattus rattus ）和野猫（ Felis catus ）被列为高度常见的脊椎动物食腐动物。当入侵食腐动物的比例较高时，入侵的欧洲黄蜂（ Vespula germanica ）也是常见的食腐动物。我们发现，当本地脊椎动物食腐动物的多样性较低时，入侵食腐动物的比例较高。我们强调，大型（顶点）本地脊椎动物食腐动物的存在可以降低入侵物种的食腐率，但入侵食腐动物可以垄断尸体资源，与本地食腐动物竞争，捕食尸体周围的其他物种，甚至促进影响其他物种和生态过程的入侵崩溃，包括改变分解率和养分循环。这种影响可能在入侵食腐动物存在的地方广泛存在，这表明需要确定是否过多或容易获得的尸体负荷正在促进或加剧入侵物种对全球生态系统的影响。
