Flooding, season and habitat interact to drive changes in vertebrate scavenging and carcass persistence rates

• Published in: Oecologia Vol. 204; no. 4; pp. 861 - 874
• Main Authors: Krige, Zyna, Spencer, Emma E., Crowther, Mathew S., Dickman, Christopher R., Newsome, Thomas M.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.04.2024; Springer Nature B.V
• Subjects: adults; Animals; Australia; Biomedical and Life Sciences; Biotic factors; Carcasses; Carrion; Climate Change; Corvidae; dead animals; Ecology; Ecosystem; Extreme weather; Flooding; Floods; Food Chain; Food chains; Food webs; Habitats; Hydrology/Water Resources; landscapes; Life Sciences; Original Research; Plant Sciences; Remote monitoring; remote sensing; Remote sensors; Scavengers; Scavenging; Seasons; species; Vertebrates; Vertebrates - physiology; warm season; Weather; Australia; Vertebrates; Carrion; Flood; Desert; Carcass
• ISSN: 0029-8549; 1432-1939; 1432-1939
• DOI: 10.1007/s00442-024-05531-0

Scavenging dynamics are influenced by many abiotic and biotic factors, but there is little knowledge of how scavengers respond to extreme weather events. As carrion is a major driver of the organisation and structure of food webs within ecological communities, understanding the response of scavengers to extreme weather events is critical in a world that is increasingly subject to climate change. In this study, vertebrate scavenging and carcass persistence rates were quantified in the Simpson Desert of central Australia; a system that experiences major fluctuations and extremes in weather conditions. Specifically, a total of 80 adult red kangaroo ( Osphranter rufus ) carcasses were placed on the landscape and monitored using remote sensor cameras. This included 40 carcasses monitored before and then 40 carcasses monitored after a major flooding event. The carcasses were monitored equally before and after the flood across different seasons (warm and cool) and in dune and interdune habitats. Overall, a total of 8124 scavenging events for 97,976 visitation minutes were recorded for 11 vertebrate species within 30 days of carcass placement pre- and post-flood. Vertebrate scavenging increased post-flood in the warm season, especially by corvids which quadrupled their scavenging events during this time. There was little difference in carcass persistence between habitats, but carcasses persisted 5.3-fold longer post-flood in warm seasons despite increased vertebrate scavenging. The results demonstrate that a flood event can influence scavenging dynamics and suggest a need to further understand how seasons, habitats and extreme weather events can drive changes in carrion-based food webs.