Data from: Scavenger assemblages and wetland management: <i>kidnapping</i> water and ecosystem services from a biodiversity hotspot

Zusammenfassung

Wetlands perform essential ecological functions, but their surface has dramatically decreased. To counteract this loss, efforts to create artificial wetlands have been undertaken. While studies comparing animal communities between artificial and natural wetlands abound, research on their comparative ecological functions is scarce. Particularly, vertebrate scavengers in aquatic ecosystems have been hardly studied despite their critical role in nutrient cycling. Our study aims to compare vertebrate scavenger assemblages and their functions in natural and artificial wetlands in Doñana, Spain, one of the most important wetlands in the Western Palearctic, to assess the impact of wetland management (natural vs. artificial hydrology) in different seasons. We placed 120 carcasses (carp paired with chicken) in natural and artificial wetlands. We recorded 22 vertebrate scavenger species efficiently consuming 100% of carrion in less than two days on average, highlighting their role in nutrient recycling. Aquatic-origin carrion was consumed faster and by a greater variety of species than terrestrial-origin carrion, facilitating the transport of essential nutrients from water to land. Although scavenger species richness was lower in artificial wetlands, they exhibited higher efficiency in carrion removal (half the time compared to natural wetlands), dominated by more opportunistic and non-native species. This suggests that “kidnapping” water from natural wetlands reduces their ability to maintain ecological functions provided by scavengers, while artificial wetlands sustain water levels and functions. Urgent regulation of water extraction from aquifers is necessary to maintain minimum groundwater levels, ensuring the functionality of this vital wetland and its ecological processes.