Belinda Cannell

Rising global temperature will have profound impacts on species and ecosystem functioning. Species existing near their thermal thresholds will be particularly vulnerable to these changes, and those species that rely on, or preferentially use, artificial structures may face pronounced effects. Gaining insights into the anticipated climate changes, both present and future, is crucial for informing conservation practices and the utilisation of artificial structures in conservation efforts. Using three years of data, we quantified and compared the temperature of artificial nest boxes installed between 1986 and 2006 and natural nest burrows of a fringing population of Little Penguins existing at the north-western limit of their range. Nest boxes were ineffective at replicating conditions of natural nests, exhibiting consistently higher daily maximum temperature (~2°C) and exceeding upper thermoneutral limits for longer than natural nests. Fine-scale biotic and abiotic nest characteristics influenced maximum nest temperature and exposure duration. Simulated temperature increase of 2°C predicted an increase in the number of days exceeding hyperthermic conditions (≥35°C) by up to 49%. Such increases will expose penguins to potentially fatal thermal conditions, particularly during the late breeding and moulting phases of their annual cycle. This study revealed that current and future thermal environments of Little Penguin terrestrial habitat on Penguin Island can exceed physiological limits for this species. Intervention to improve artificial nests and better quantify consequences is urgently needed given recent estimates of a declining population and increasing risk of local extinction.

This is a record for the data collected from surveys of selected terrestrial environmental values at Ashmore Reef Marine Park that were carried out in 2019.

In early 2019 Parks Australia commissioned CSIRO to undertake a survey of selected marine and terrestrial environmental values at Ashmore Reef Marine Park. For the terrestrial component, the required elements were to quantify the diversity and abundance of native and non-native plant species, determine the population status and diversity of birds on the islands and to determine the abundance of non-native invasive tropical fire ants. The remit included any evidence of interactions between the fire ants and native fauna, especially birds and turtles.