Spatiotemporal patterns of carrion biomass of marine tetrapods at the ocean-land interface on the southern Brazilian coastline

Abstract

Quantifying how much carrion is produced temporally and spatially in ecosystems is considered one of the most important aspects of carrion ecology. Marine-derived inputs transferred from the ocean to terrestrial ecosystems are the principal source of energy and biomass for many coastal ecosystems. Here, we provide a comprehensive quantification of the carrion biomass of marine tetrapods across space and time at the ocean-land interface on the Brazilian coastline. Based on 3 large datasets, we estimated carrion biomass of 57274 marine tetrapods beached along 1980 km of coastline over a 3 yr period (2016-2019). A total of 1744986 kg of carrion biomass was estimated from 76 species, ranging from a total of 30 g to 14082 kg for each species. The 10 most abundant species accounted for 91.78% of total records but only 21.28% of total estimated biomass. We highlight the importance of both migratory and resident marine tetrapods as a predictable resource for the Brazilian coastline, especially in the winter and spring. Although baleen whales contributed higher values of carrion biomass, their true availability as a food source is affected by management procedures adopted after stranding events. A significant amount of carrion biomass is removed every year from the Brazilian coastal system. It is therefore imperative to assess the impacts of management procedures on the ecology of scavengers and the entire coastal system.