No menu items!

COSTA RICA'S LEADING ENGLISH LANGUAGE NEWSPAPER

HomeCosta RicaThe Mystery of the Orange Howler Monkeys in Costa Rica

The Mystery of the Orange Howler Monkeys in Costa Rica

Biologist at the University of Costa Rica Oscar M. Chaves Badilla is a primate specialist studying a phenomenon that seems to appear almost exclusively in Costa Rica. That is the discoloration of certain Howler Monkeys throughout the country that gives them an orange pigmentation.

The study got its start almost ten years ago when the first Howler Monkeys developed this anomaly which has risen over the year to include by some counts over two hundred animals.

There are several theories as to why this may be happening but two of them seem to be getting the most attention.

The first one points to the potential exposure of the primates to pesticides and insecticides in the areas nearby where the animals live or directly on food the monkeys may eat from abutting commercial agricultural areas.

The other suggestion points to loss of habitat and forest corridors that allow the animals to travel and therefore breed with members of other troops of Howlers. The result being a lack of genetic diversity, resulting in more animals with the discoloration caused by inbreeding.

There is also a potential third theory held by some not associated with the study, that suggest that the original case, or cases, were a rare genetic exception and actually may have some dominant traits. It purports that the actual interaction of the monkeys with each other over the past decade has resulted in one cluster of discolored animals being spread throughout Costa Rica.

The research appears to by on Professor Badilla’s side but further investigation would determine if action is needed to address the issue of pesticides, habitat destruction or both.

Trending Now

Costa Rica Approves U.S. Coast Guard Boats for 2026 Anti-Drug Operations

Lawmakers in Costa Rica's Legislative Assembly have given the green light for up to 195 U.S. Coast Guard vessels to access the country's ports...

Influenza Variant Circulates in Costa Rica as Health Officials Urge Prevention

Health officials in Costa Rica have confirmed the presence of a new influenza A(H3N2) variant, subclade K, as cases of respiratory illnesses rise during...

Top Prize Unsold in Costa Rica’s Gordo Navideño Lottery Draw

The Gordo Navideño 2025 draw wrapped up last night with a twist that left many stunned: the top prize went unclaimed because the winning...

How to Travel with Pets in Costa Rica Without Issues

Travelers who plan to bring their dogs or cats into or out of the country often face strict rules set by the National Animal...

Costa Rica’s President Attacks Opponents After He keeps His Immunity

Costa Rica’s President Rodrigo Chaves lashed out at opposition lawmakers after Congress rejected a request to strip him of immunity, a step that could...

MOPT Announces Route 27 Traffic Changes for January to Ease Returns

The Ministry of Public Works and Transport (MOPT) has set reversible lanes on Route 27 for every Sunday in January 2026. This step aims...
Costa Rica Coffee Maker Chorreador
Costa Rica Coffee Maker Chorreador
Costa Rica Travel Insurance
Costa Rica Travel

Latest News from Costa Rica