In the state of Tabasco, where temperatures are forecast this week to surpass 45 degrees Celsius (113 Fahrenheit), local media have reported up to 85 deaths, while local authorities have confirmed the trend without providing a death toll.

In a statement over the weekend, Tabasco’s Civil Protection agency attributed the monkeys’ deaths to dehydration.

A source from the agency told Reuters on Monday that monkeys have been confirmed dead in three municipalities of the state.

In a forest outside Camalcalco, Tabasco, volunteers collected the corpses of mantled howler monkeys that died from high temperatures, before placing buckets of water and fruit to try to stave off more deaths.

The mantled howler monkey is classified as vulnerable on the International Union for Conservation of Nature Red List.

Volunteers observe dead monkeys that fell from trees amid a heat wave in Buena Vista, Comalcalco, Mexico on May 18, 2024. Luis Manuel Lopez/Reuters

A Civil Protection worker pours lime over the bodies of monkeys in Buena Vista, Comalcalco, Mexico on May 18, 2024. Luis Manuel Lopez/Reuters

“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,” Mexican President Andrés Manuel López Obrador, who comes from Tabasco, said on Monday when asked about the monkey deaths.

“So, yes, we have to care for the animals and yes we are going to do it,” he said in his regular news conference.

Later on Monday, Mexico’s environment ministry said in a statement that it was coordinating efforts to address the monkeys’ deaths, which it attributed to several possible reasons, including “heat stroke, dehydration, malnutrition or the spraying of crops with toxic agro-chemicals.”

The country has been grappling with soaring and deadly temperatures for weeks. Mexico’s health ministry reported a preliminary count of 26 people who have died from heat-related causes between the start of Mexico’s heat season on March 17 and May 11.

Extreme heat is being driven by human-caused climate change, in combination with El Niño, a natural climate pattern which affects global weather.

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