Baby Howler Monkey with Bot Fly Lesion (image) Smithsonian Tropical Research Institute Share Print E-Mail Caption An ongoing study of the cause of death of howler monkeys on Barro Colorado has identified the howler monkey bot fly Cuterebra baeri as the single most important factor. Very young monkeys are the most affected. Credit Katie Milton Usage Restrictions Credit: Katie Milton Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.