Mexico’s Heatwave Causing Howler Monkeys to Drop Dead from Trees

Heatwaves throughout Latin America have been major indicators of climate change and we continue to see the impact not only on humans and the environment but the wildlife. Mexico has seen unprecedented levels of extreme heat in various areas upwards of 113 degrees Fahrenheit since March. Mexico City residents have been rationing water for months and officials estimate parts of the capital’s central valley might not have enough water to pump into the city by June 26 even if it begins to rain, Axios reported. At least a dozen cities in Mexico have already broken records for high temperatures in recent days, leading to 48 deaths from heat stroke and dehydration in two months, according to the Ministry of Health. Since May 16, it’s become so hot in the state of Tabasco that mantled howler monkeys, which are classified as vulnerable on the International Union for Conservation of Nature (IUCN) Red List, were discovered falling dead from the trees in the town of Tecolutilla. Since then, at least 157 dead monkeys have been found by residents, according to the government.

“They were falling out of the trees like apples,” local wildlife biologist Gilberto Pozo told AP News. “They were in a state of severe dehydration, and they died within a matter of minutes.”

Five of them were able to be rescued by a volunteer fire-and-rescue squad and taken to local veterinarian Dr. Sergio Valenzuela, who was able to save them from their heatstroke symptoms, including dehydration and a fever. But it’s a symptom of a much larger problem related to climate change, and other animals and humans will undoubtedly be affected by these extreme temperatures as well as drought, fires, and logging activities, according to AP News.

According to the United Nations, climate change is a term to describe “long-term shifts in temperatures and weather patterns. Such shifts can be natural, due to changes in the sun’s activity or large volcanic eruptions. But since the 1800s, human activities have been the main driver of climate change, primarily due to the burning of fossil fuels like coal, oil and gas.” This has drastic effects on human and wildlife including food supply, habitat destruction, and basic survival. Howler monkeys can grow upwards of three fee tall with a tail just as long and it’s known for its lion-like roar (hence the name) and has a projected life span of upwards of 20 years.

But because of Mexico’s recent heat wave, the rescued monkeys have had to be hooked up to IV drips with electrolytes with ice placed on their hands and feet to re-stimulate them. Over time, they have become energetic and aggressive again but the high number of deaths remains ongoing. Pozo has noted that it’s not only the heat that’s a problem but also logging activities that reduce the number of trees in the area that provide the monkeys with water, shade, and fruit. He has also seen a significant number of birds and reptiles affected. The axolote is endangered due to the droughts as many species only inhabit freshwater lakes and rivers in Mexico.

All across Mexico, people are feeling the heat as well, with some states like Tamaulipas setting record-breaking temperatures of 117 degrees Fahrenheit. This is partly due to local lakes and dams drying up, below-average rainfall, and decreasing water supplies. Residents have also seen electricity blackouts, which only worsens the hot conditions. In the meantime, President Andrés Manuel López Obrador has pledged government support to Dr. Sergio Valenzuela and his efforts.

“It is because the heat is so strong. I’ve been visiting the states for a long time and I have never felt it as much as now,” he told Reuters. “So, yes, we have to care for the animals and yes we are going to do it.”

The Mexican environment ministry is currently coordinating efforts to investigate and address the deaths of the howler monkeys in collaboration with locals from Tabasco.