Holocene vertebrate fossils aid the management and restoration of Australian ecosystems

Abstract

This review arose from the observation that 'long-term' ecological studies could be extended by orders of magnitude if palaeo-ecological data are incorporated.Summary European-settlement-related impacts over the past 200 years pose many challenges for the conservation and restoration of Australia's ecosystems. Landscape modification, associated habitat loss and the introduction of exotic species have caused the extinction and mainland extirpation of numerous vertebrates. This process happened so quickly that many species became locally or functionally extinct before their presence was documented. A growing body of research on Holocene fossil accumulations is providing insights into the composition and biogeography of Australian ecosystems prior to European settlement. This review explores the similarities between palaeo-and neo-ecology and how Holocene (last 10,000 years) assemblages can be used by neo-ecologists, conservation managers and policy makers to identify and fill gaps in knowledge and contribute to the management and restoration of Australia's degraded ecosystems.

Survival histories of marsupial carnivores on Australian continental shelf islands highlight climate change and Europeans as likely extirpation factors: implications for island predator restoration

“…For example, while the eastern and western quolls were formerly very common and widespread, only limited museum samples exist to establish their former distributions. Additionally, shifting baselines and intergenerational amnesia can result in primary components being lost from modern knowledge (McDowell, 2014;Alleway & Connell, 2015). Historical accounts and sub-fossil specimens are increasingly critical components of modern efforts at re-establishing species former distributions, and hence the associated ecosystems.…”

Late-Holocene mammal fauna from southern Australia reveals rapid species declines post-European settlement: Implications for conservation biology

“…Conservation action frequently requires data extracted from species distributions to infer optimum habitat, how biota respond to environmental change and to establish conservation status. Species distributions are also key to determining baseline reference conditions which are potentially useful for ecosystem restoration (McDowell, 2014). As species distributions are dynamic and respond to changes in their environment (Dietl and Flessa, 2011), past and modern distributions can be enormously different.…”

“…Analysis of late Holocene assemblages and improved taxonomic assessments is revealing that species distributions have been fundamentally changed by extirpations and range shifts in response to European-driven environmental changes. Many species disappeared from parts of their pre-European distributions, or became extinct, soon after colonisation and before any historical records of their existence were made (Armstrong, 2003; Bilney et al, 2010; McDowell, 2014; Ride, 1968). This has resulted in biodiversity declines being underestimated and a distorted perception of the status of Australia’s mammals (Bilney, 2014).…”

“…Establishing the distribution and composition of Holocene faunal communities increases the accuracy of data extrapolated from species distributions that are commonly used for modern conservation management, that is, extent of biodiversity losses, species habitat tolerances, range expansions and contractions as well as ecology (Bilney, 2014; McDowell, 2014). Fossils can be used to distinguish between natural change and ecosystem disturbance events, for example, anthropogenic impacts (Dietl and Flessa, 2011; Lyman, 2012), define restoration baselines (Bilney, 2014; McDowell, 2014) and identify refugia (Byrne, 2008; Van der Plicht et al, 2015). Post-European faunas in particular regions may constitute up to as little as 20% of their pre-European former biodiversity (McDowell, 2014).…”

“…Fossils can be used to distinguish between natural change and ecosystem disturbance events, for example, anthropogenic impacts (Dietl and Flessa, 2011; Lyman, 2012), define restoration baselines (Bilney, 2014; McDowell, 2014) and identify refugia (Byrne, 2008; Van der Plicht et al, 2015). Post-European faunas in particular regions may constitute up to as little as 20% of their pre-European former biodiversity (McDowell, 2014). Thus, pre-European Holocene faunas are considered more appropriate baselines for restoration goals in Australia than their contemporary counterpart (Froyd and Willis, 2008; Hayward, 2009; McDowell, 2014).…”