Scavenging in the realm of senses: smell and vision drive recruitment at carcasses in Neotropical ecosystems

Social information, acquired through the observation of other individuals, is especially relevant among species belonging to the same guild. The unpredictable and ephemeral nature of carrion implies that social mechanisms may be selected among scavenger species to facilitate carcass location and consumption. Here, we apply a survival-modelling strategy to data obtained through the placement and monitoring of carcasses in the field to analyse possible information transmission cascades within a Neotropical scavenger community. Our study highlights how the use of different senses (smell and sight) within this guild facilitates carcass location through the transmission of social information between species with different carrion foraging efficiencies. Vultures with a highly developed sense of smell play a key role in this process, as they are the first to arrive at the carcasses and their presence seems to serve as a visual cue for other species to locate the resource. Our study supports the local enhancement hypothesis within scavengers, whereby individuals locate carcasses by following foraging heterospecifics, also suggesting the importance of the sense of smell in the maintenance of the community structure. L.N.A., Z.M.R. and E.S.G. were supported by the Generalitat Valenciana and the European Social Fund (grant nos. ACIF/2019/056, APOSTD/2019/016, SEJI/2018/024, respectively). Z.M.R. was also funded by the Junta de Andalucía (grant no. POSTDOC_21_00353). E.S.G. also received the grant RYC2019-027216-I funded by MCIN/AEI/ 10.13039/501100011033 and by ESF Investing in your future. O.O. was funded by Academy of Finland (grant no. 309581), Jane and Aatos Erkko Foundation, Research Council of Norway through its Centres of Excellence Funding Scheme (grant no. 223257), and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 856506; ERC-synergy project LIFEPLAN).