It is well documented that Andean bears (Tremarctos ornatus) feed extensively on plants and carrion, but their hunting habits remain understudied. Better understanding and documentation of Andean bear feeding ecology can improve conservation efforts for this vulnerable species. Here, we report an observation of an Andean bear hunting and capturing a wild guinea pig (Cavia aperea) in Chingaza National Natural Park, in Cundinamarca, Colombia. The sighting occurred in January 2023 by a team of conservationists, and we provided photographic evidence and details of the encounter. Our observation suggests that Andean bears are capable hunters of small rodents, indicating that hunting may play a more important role in the ecology of Andean bears than previously appreciated and highlighting the need for a better understanding of this feeding behaviour.

Two domestic guinea-pigs (Cavia porcellus), bought in Pinheiros, São Paulo State, Brazil, were taken by their owners a farm in the rural district of Capão Bonito, close to the Atlantic Forest, São Paulo, where they both developed tumour-like and ulcerating lesions on the ears. The causative agent was identified as Leishmania (L.) enriettii, based on biological characters and isoenzyme profiles. Sources of the parasite in wild mammals, and the possible sandfly vector species discussed.