A vulnerability assessment framework for terrestrial invertebrate species threatened by wildlife trade

Wildlife trade is an emerging threat to terrestrial invertebrates in Australia, yet its impact on native populations remains poorly quantified. Short range endemic (SRE) species, often characterised by restricted geographic ranges, low reproductive output, low vagility, and specialised habitat conditions, are particularly vulnerable to anthropogenic pressures, including over-exploitation via wild harvesting. Using a multi-year dataset of Australian invertebrate trade records, we identified species that are both utilised in the pet trade and exhibiting SRE traits, and assessed their risk of population decline by integrating trade frequency with species distribution, abundance, and biological vulnerability. We identified 266 species traded in Australia with an area of occupancy less than 500 square kilometres, with arachnids disproportionately represented among those at greatest relative risk of population decline from over-exploitation. While these rankings should be interpreted as a methodological demonstration rather than a definitive measure of extinction risk, they provide a transparent approach for screening species where trade pressure may intersect with biological vulnerability. To the best of our knowledge, this is the first tested approach to holistically assess this risk in invertebrates. We present a proof-of-concept framework for quantifying trade-related vulnerability in terrestrial invertebrates, providing a transferable approach that can be refined and applied across a wide range of taxa threatened by wildlife trade.