An investigation into the response of landscape scale threats on a threatened amphibian

<p dir="ltr">Amphibians are the most threatened vertebrate group globally, with over 40% of species at risk of extinction. Habitat transformation, invasive species, disease, pollution, and climate change are driving widespread population declines. These threats rarely act in isolation; rather, they interact and often compound their effects, further undermining species’ resilience. The green and golden bell frog (Litoria aurea), a species of conservation concern, provides an ideal case study for examining how amphibians respond to multiple, often concurrent, environmental threats operating at landscape scales. The overarching aim of this thesis was to investigate how multiple environmental threats influence the behaviour, ecology, and persistence of L. aurea, and to evaluate management strategies that may mitigate these impacts. Specifically, this research sought to (1) synthesise existing knowledge on how habitat transformation and chytrid fungus interact to influence amphibian ecology, with a focus on the terrestrial environment; (2) investigate seasonal habitat selection during winter and assess its implications for thermoregulation and chytrid susceptibility; (3) examine the influence of invasive predators on breeding habitat use and evaluate how predator presence may restrict reproductive opportunities; and (4) assess population responses to climate extremes by quantifying survival and recruitment dynamics under prolonged dry and wet climatic phases. These objectives address the broader question of how L. aurea responds to interacting threats at local and landscape scales, and how conservation efforts might be designed to enhance species resilience under ongoing environmental change. Using a combination of field and experimental studies, including radio-tracking, habitat assessments, and long-term population monitoring, this research examined how L. aurea copes with invasive predators, disease susceptibility, and climate variability, and explored the implications for conservation management.</p>