Barn owl pellets collected in coastal savannas yield two additional species of small mammals for French Guiana

Abstract

A sample of 251 pellets regurgitated by the barn owl in an old building located in Sinnamary (French Guiana) provided a rare opportunity to get a preliminary inventory of small rodents and opossums living in grassy savannas along the coastal non-forested landscapes of this Guianan region. From a total of 329 specimens of vertebrate remains, we focused on 259 small rodents and opossums that could be positively identified. Two species previously unknown in French Guiana were evidenced: a very small opossum of the genus Cryptonanus and the medium-sized terrestrial rodent Sigmodon alstoni. Although Cryptonanus was an unexpected finding so far away from its Amazonian distribution area, the presence of Sigmodon in French Guiana fills a gap between Suriname and Brazilian Amapa where this species is typical of grassy savannas. The species of small mammals most commonly preyed upon by the barn owls of Sinnamary was a large semi-aquatic rodent, Holochilus sciureus, followed in decreasing order by two sigmodontines typical of non-forested ecosystems: Oligoryzomys fulvescens and Zygodontomys brevicauda.