Field protocol for the capture of wild howler monkeys (Alouatta caraya): low-cost innovative strategies to increase safety and effectiveness

ARGIBAY H; RODRIGUEZ PLANES, L; OROZCO M. M.

Nueva York

Conferencia; 53RD AAZV/EAZWV ANNUAL CONFERENCE; 2021

Capture of wild neotropical primates demands the development of an adequate anesthetic protocol and appropriate management of the individual and/ groups, adapted to the environmental conditions.2 The complete procedure must allow safe capture and rapid recovery for in situ release.1 In the framework of an eco-epidemiological study, 141 howler monkeys from a wild population were captured in the Argentine Humid Chaco. We describe the field protocol carried out to perform the captures, highlighting the pros and cons observed based on the specificities of the Alouatta genus, characterized by a strong and prehensile tail, hairless ventro-distally, turning their capture into a real challenge.3 The anesthetic protocol consisted of ketamine 5.5-18 mg/kg and xylazine 1.3-3.5 mg/kg injected via disposable darts (Pneudart Type P) directed towards the hindquarters and fired from a compressed air rifle (Pneudart model 176B).4 Additional equipment included a polyester canvas to receive the animal, a telescopic ladder, a pole with a hook-shaped head and climbing equipment. During the procedure for collecting morphometric measurements and biological samples, anesthetic monitoring was performed with a multiparametric monitor. Thirty minutes after induction, monkeys were administered yohimbine (0.3-1.0 mg/kg) and were placed in a net installed in the low forest until recovery. No fatalities occurred during the study. Capturing free-ranging monkeys using anesthetic darts implies undeniable risks, but the careful development of alternate strategies to deal with unpredictable fieldwork scenarios, clear decision criteria, and adaptive management protocols proves it is possible to do it effectively and safely.ACKNOWLEDGMENTSThe authors would like to thank the Natural Resource Department of Chaco Province and especially to the local community of Pampa del Indio. This study was supported by awards from Universidad de Buenos Aires (UBACYT 20020100100944), Agencia Nacional de Promoción Científica y Tecnológica (PICT 2011?2072, PICTO?Glaxo 2011?0062), and Consejo Nacional de Investigaciones Científicas y Técnicas (PIP 2012-2015)LITERATURE CITED1. Cunningham EP, Unwin S, Setchell JM. Darting Primates in the Field: A Review of Reporting Trends and a Survey of Practices and Their Effect on the Primates Involved. Int J Primatol. 2015;36:911?932. 2. Glander KE. Darting, anesthesia, and handling. In: Sterling EJ, Bynum N, Blair ME (eds.). Primate ecology and conservation: A handbook of techniques. Oxford (UK): Oxford University Press; 2013. p. 27?39. 3. Kowalewski MM, Garber PA, Cortes-Ortiz L, Urbani B, Youlatos D. Howler monkeys: adaptive radiation, systematics, and morphology. Developments in primatology: Progress and prospects. New York (NY): Springer; 2015. 448 p. 4. West GD, Heard DJ, Caulkett N. Zoo animal and wildlife immobilization and anesthesia. Ames (IA): John Wiley & sons Inc; 2014.