The brown howler monkey (Alouatta guariba clamitans) is listed as Critically Endangered in Argentina, where a small number persist in the northeastern portion of the country. Although habitat loss and ...

Brown howler monkeys are experiencing a devastating die-off in southern Mexico, with at least 138 reported deaths between May 4 and May 21. The fatalities have been linked to soaring temperatures, ...

At the start of her 2008 field season at El Parque El Piñalito in the Misiones province in northeastern Argentina, Ilaria Agostini knew something was terribly wrong. Agostini has studied Misiones' two ...

In a vulnerable forest in southeastern Brazil, where the air was once thick with the guttural chatter of brown howler monkeys, there now exists silence. Yellow fever, a virus carried by mosquitoes and ...

A rapidly moving yellow fever virus that has killed thousands of brown howler monkeys in Brazil may be creating an opportunity for the monkeys' critically endangered competitor. "It's like a ...

When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Two northern muriquis, or woolly spider monkeys (Brachyteles hypoxanthus) peer down from a tree ...

From 2007 to 2009, a devastating yellow fever virus outbreak nearly decimated brown and black and gold howler monkey populations at El Parque El Piñalito in northeastern Argentina. An international ...

Brown howler monkeys are extremely susceptible to yellow fever, and an outbreak can cause local extinctions. Hundreds of brown howler monkeys are estimated to have died at the RPPN-FMA reserve due to ...