Abstract:
We explored the ecological and historical factors that led to formation of the unique guild of native and introduced mammalian herbivores between 5 and 1000 kg in northern Australia. Following the disappearance of large native herbivores about 46 kya, and until the arrival of Europeans and their livestock, the only herbivorous mammals were mid-sized endemic marsupial macropods, which continued to utilise the same vegetation as their much larger former neighbours. Only one species of contemporary native herbivore has an adult bodyweight approaching 100 kg, and for the past 150-200 years, the total biomass of introduced domestic and wild vertebrate herbivores has massively exceeded that of native herbivorous species. We conclude that the current guild of native and introduced mammalian herbivores differentially utilises the landscape ecologically. However, climate- and anthropogenically related changes due to fire, drought, flooding, predation and introduced weeds are likely to have significant impacts on the trajectory of their relative ecological roles and populations. Given their differing ecological and dietary characteristics, against this backdrop, it is unclear what the potential impact of the dispersal of deer species could have in northern Australia. We hence focus on whether sufficient knowledge exists against which the potential impacts of the range expansion of three deer species can be adequately assessed and have found a dearth of supporting evidence to inform appropriate sustainable management. We identify suitable research required to fill the identified knowledge gaps.
摘要:
我们探索了生态和历史因素,这些因素导致在澳大利亚北部形成了5至1000公斤的本地和引入的哺乳动物草食动物独特行会。在大约46kya的大型本地食草动物消失之后,直到欧洲人和他们的牲畜到来,唯一的食草哺乳动物是中型特有的有袋大型动物,继续使用与以前更大的邻居相同的植被。只有一种当代本地食草动物的成年体重接近100公斤,在过去的150-200年里,引进的家养和野生脊椎动物草食动物的总生物量大大超过了本地草食动物。我们得出的结论是,当前的本地和引入的哺乳动物草食动物行会在生态上不同程度地利用了景观。然而,火灾导致的气候和人为相关变化,干旱,洪水,捕食和引入的杂草可能会对其相对生态角色和种群的轨迹产生重大影响。鉴于它们不同的生态和饮食特征,在这种背景下,目前尚不清楚在澳大利亚北部,鹿物种的传播可能会产生什么潜在影响。因此,我们将重点放在是否存在足够的知识上,可以根据这些知识充分评估三种鹿物种的射程扩大的潜在影响,并且发现缺乏支持证据来为适当的可持续管理提供信息。我们确定了填补已确定的知识空白所需的合适研究。