Analyzing Outbreaks in Brown Howler Populations

CBSG was invited to facilitate and create population models for the Brown Howler Monkey Conservation Workshop, where participants explored the dynamics of yellow fever outbreaks and their impact on howler mortality.

The Situation
The howler monkey (Alouatta guariba) is one of the endemic primate species of South America’s Atlantic Forest. Howlers are classified globally as Least Concern by the IUCN due to the species’ presence in most of Brazil’s Atlantic Forest conservation units. However, the brown howler (Alouatta guariba clamitans) was reclassified in 2012 from Endangered to Critically Endangered in Argentina. In 2008-2009, severe yellow fever outbreaks decimated brown howler populations in southern Brazil and northern Argentina, driving the already small population in Misiones Province to the verge of extinction. Due to their high susceptibility to yellow fever, howler monkeys are considered “disease sentinels”: important indicators for the arrival of an outbreak in an area that can lead health officials to take action.

CBSG's Role
CBSG was invited to facilitate and create population models for the Brown Howler Monkey Conservation Workshop held in Andresito and Puerto Iguazú, Argentina. Eleven specialists in howler biology and disease ecology gathered to conduct a threat analysis for brown howlers in Argentina. Participants explored the dynamics of yellow fever outbreaks and their impact on howler mortality using software for population viability analysis (Vortex) and disease epidemiology (Outbreak), and concluded that yellow fever was the biggest threat to the species. Critical information gaps were identified and the group developed a list of prioritized objectives and actions to improve long-term persistence of the species in Argentina.

The Results
Workshop participants created a set of 12 priority actions, aimed at reaching specific objectives. A Brown Howler Monkey Conservation group was created, and several Brazilian colleagues were invited to join. Workshop results were communicated to the scientific community through conference proceedings and published papers. A Spanish summary of the workshop was distributed to all local stakeholders. With support from the Instituto Nacional de Medicina Tropical (INMeT), mosquito trapping and isolation of yellow fever virus are ongoing. Analysis of fecal samples obtained from surveys using trained dogs will be used to estimate brown howler distribution and abundance in Misiones and to evaluate local metapopulation genetic diversity.

More

• Brown Howler Monkey Conservation Workshop Report
• Visit the Brown Howler Monkey Conservation group Facebook for real-time updates on the status of brown howlers: https://www.facebook.com/procarayarojo.
• Paper in Tropical Conservation Science: Building a Species Conservation Strategy for the brown howler monkey (Alouatta guariba clamitans) in Argentina in the context of yellow fever outbreaks
• More CBSG Highlighted Stories.

Photo by Ilaria Agostini.