Hawke Tahneal, Bates Hayley, Hand Suzanne, Archer Michael, Broome Linda
PANGEA Research Centre, Biological, Earth and Environmental Sciences, University of New South Wales, Kensington, NSW, Australia.
Office of Environment and Heritage, Queanbeyan, NSW, Australia.
PeerJ. 2019 Jan 24;7:e6307. doi: 10.7717/peerj.6307. eCollection 2019.
The Mountain Pygmy-possum () is a critically endangered marsupial, endemic to alpine regions of southern Australia. We investigated the diet of a recently discovered population of the possum in northern Kosciuszko National Park, NSW, Australia. This new population occurs at elevations well below the once-presumed lower elevation limit of 1,600 m.
Faecal material was analysed to determine if dietary composition differed between individuals in the newly discovered northern population and those in the higher elevation southern population, and to examine how diet was influenced by rainfall in the southern population and seasonal changes in resource availability in the northern population.
The diet of in the northern population comprised of arthropods, fruits and seeds. Results indicate the diet of both populations shares most of the same invertebrate orders and plant species. However, in the absence of preferred food types available to the southern population, individuals of the northern population opportunistically consumed different species that were similar to those preferred by individuals in higher altitude populations. Differing rainfall amounts had a significant effect on diet, with years of below average rainfall having a greater percentage composition and diversity of invertebrates. Seasonal variation was also recorded, with the northern population increasing the diversity of invertebrates in their diet during the Autumn months when Bogong Moths () were absent from those sites, raising questions about the possum's dependence on the species.
Measurable effects of rainfall amount and seasonal variation on the dietary composition suggest that predicted climatic variability will have a significant impact on its diet, potentially impacting its future survival. Findings suggest that it is likely that is not restricted by dietary requirements to its current pattern of distribution. This new understanding needs to be considered when formulating future conservation strategies for this critically endangered species.
山地侏儒负鼠是一种极度濒危的有袋动物，原产于澳大利亚南部的高山地区。我们对澳大利亚新南威尔士州科西阿斯科山国家公园北部最近发现的一群负鼠的饮食进行了调查。这个新种群所处的海拔远低于曾经假定的1600米的海拔下限。
分析粪便物质，以确定新发现的北部种群个体与海拔较高的南部种群个体的饮食组成是否存在差异，并研究南部种群的降雨以及北部种群资源可用性的季节性变化如何影响饮食。
北部种群的山地侏儒负鼠的饮食包括节肢动物、水果和种子。结果表明，两个种群的饮食在大多数无脊椎动物目和植物种类上是相同的。然而，由于南部种群没有可获取的首选食物类型，北部种群的个体机会性地食用了与高海拔种群个体偏好的物种相似的不同物种。降雨量的差异对饮食有显著影响，降雨量低于平均水平的年份，无脊椎动物的组成百分比和多样性更高。还记录到了季节性变化，在秋季，当博贡蛾不在那些地点出现时，北部种群饮食中的无脊椎动物多样性增加，这引发了对负鼠对该物种依赖性的质疑。
降雨量和季节性变化对饮食组成的可测量影响表明，预测的气候变异性将对其饮食产生重大影响，可能影响其未来生存。研究结果表明，山地侏儒负鼠的饮食需求可能并不限制其当前的分布模式。在为这种极度濒危物种制定未来保护策略时，需要考虑这一新认识。
