Important issues facing insect conservation in Australia: now and into the future

Abstract

Studies of insect biodiversity and conservation in Australia have been severely limited by the many undescribed species and paucity of taxonomists and insect ecologists. In this review, I discuss important issues facing insect conservation, namely, key threatening processes, threats to habitats and ecological communities, the importance of maintaining insect interactions, the value of vegetation remnants in agricultural ecosystems and the importance of community participation, and provide recommendations for the conservation management of invertebrates and their habitats. Major threats to insect biodiversity continue from habitat loss through broadscale clearing of native vegetation, invasion by weeds, habitat fragmentation, loss of natural corridors and inappropriate fire regimes. Other threats include disturbance of plant communities on hilltops, creek embankments and in water courses, pesticide regimes, trampling and grazing by stock and feral animals, and exotic predators. Climate change affects those insects constrained by their thermal and moisture tolerances (climate envelopes), potentially influencing their distribution, development and reproduction, by disrupting diapause and aestivation or inducing torpor. Protected areas under State jurisdiction are at risk without Commonwealth protection and increasingly threatening those insects occurring only in national parks and other conservation areas. For effective conservation of mainland national parks, overarching national EPBC Act legislation is needed to protect parks for conservation of animal and plant diversity and natural landscapes. Retention of native vegetation as refuges for beneficial insects near farmlands is known to contribute to environmentally clean pest control. Information on conservation of beneficial insects and their dependence on native plants as habitats is needed by farmers to promote identification and protection of natural refuges for pollinators, parasitoids and predators and to support the case against indiscriminate tree clearing. Important community conservation activities are underway in several States and Territories, but to be effective, increased support and funding from appropriate agencies is required.

Lots of loss with little scrutiny: The attrition of habitat critical for threatened species in Australia

“…In Australia, at least 90 native species have become extinct since European settlement (Australian Government, ). There are many drivers of this extinction crisis including invasive species and changed fire regimes, yet the destruction of vegetation due to agricultural activities, infrastructure, mining, and urbanization is the most significant threat to biodiversity (Braby, ; Cresswell & Murphy, ; Sands, ; State of the Environment Committee, ; Taylor et al, ). Since European settlement, Australia has lost 33% of all native vegetation, with that loss concentrated in agricultural and coastal regions (National Land and Water Resources Audit, ).…”

Insect threats and conservation through the lens of global experts

“…Along with ample land protected, it seems that conservation of insect biodiversity also largely depends on managing sufficient and suitable habitats. For instance, land clearing and removal of over-mature and veteran trees have been identified as threats to some of the orders with many species such as Hymenoptera, Coleoptera, Lepidoptera, and Diptera (Sands, 2018). Therefore, land management practises that avoid harvesting large old growth trees would be of conservation importance for many insect species worldwide (Jörg et al, 2016).…”

Are insects and other invertebrates in decline in Australia?

“…They are all narrow-range endemics, half of which occurred on islands, which have been impacted by a range of anthropogenic processes, most notably habitat loss, deterioration of habitat quality and invasive species. Essentially, they exemplify the key threatening processes for insects and allied invertebrates summarised in a recent symposium on insect conservation in Australia (Taylor 2018;Taylor et al 2018;Sands 2018;Braby 2018;New 2018;Gagic et al 2018;Carlile et al 2018). However, it is clear from the scientific literature that there are countless cases of documented invertebrate extinctions of species that simply have not been formally listed under any of the state/territory, national (EPBC Act 1999) or international (IUCN Red List of Threatened Species) conservation schedules.…”

“…Essentially, they exemplify the key threatening processes for insects and allied invertebrates summarised in a recent symposium on insect conservation in Australia (Taylor ; Taylor et al . ; Sands ; Braby ; New ; Gagic et al . ; Carlile et al .…”