Multi‐taxon biodiversity responses to the 2019–2020 Australian megafires

Abstract

Conditions conducive to fires are becoming increasingly common and widespread under climate change. Recent fire events across the globe have occurred over unprecedented scales, affecting a diverse array of species and habitats. Understanding biodiversity responses to such fires is critical for conservation. Quantifying post‐fire recovery is problematic across taxa, from insects to plants to vertebrates, especially at large geographic scales. Novel datasets can address this challenge. We use presence‐only citizen science data from iNaturalist, collected before and after the 2019–2020 megafires in burnt and unburnt regions of eastern Australia, to quantify the effect of post‐fire diversity responses, up to 18 months post‐fire. The geographic, temporal, and taxonomic sampling of this dataset was large, but sampling effort and species discoverability were unevenly spread. We used rarefaction and prediction (iNEXT) with which we controlled sampling completeness among treatments, to estimate diversity indices (Hill numbers: q = 0–2) among nine broad taxon groupings and seven habitats, including 3885 species. We estimated an increase in species diversity up to 18 months after the 2019–2020 Australian megafires in regions which were burnt, compared to before the fires in burnt and unburnt regions. Diversity estimates in dry sclerophyll forest matched and likely drove this overall increase post‐fire, while no taxon groupings showed clear increases inconsistent with both control treatments post‐fire. Compared to unburnt regions, overall diversity across all taxon groupings and habitats greatly decreased in areas exposed to extreme fire severity. Post‐fire life histories are complex and species detectability is an important consideration in all post‐fire sampling. We demonstrate how fire characteristics, distinct taxa, and habitat influence biodiversity, as seen in local‐scale datasets. Further integration of large‐scale datasets with small‐scale studies will lead to a more robust understanding of fire recovery.

Coastal Biodiversity Assessment Aided by Citizen Science Volunteers: A Look at the Italian Central Adriatic

“…CS initiatives are frequently aimed at specific tasks, such as implementing environmental education for youth [30][31][32], studying the presence of rare or less attractive species [33,34], or even monitoring biological invasions [35,36]. Yet, the studies that simultaneously analyse organisms belonging to distinct kingdoms are still scarce [37][38][39]. Moreover, the use of CS to support the implementation of a comprehensive observation framework, which includes observations of many taxa in various terrestrial, aquatic, and transitional dynamic systems in coastal regions, has not been attempted thus far, and it is necessary to enhance our comprehension of how CS can function in such a context.…”