Insect Populations Collapse Globally, 98 percent in Puerto Rico

Scientists have found that 98% of ground insects in Puerto Rico’s Luquillo rainforest have vanished in the last 35 years. A true collapse of the insect populations in the rainforest, experts are calling the study published in October hyper-alarming.

Scientists returning to the rainforest in Puerto Rico after 35 years found the insect population had collapsed. At ground level 98% of the insect populations are gone. In the canopy, 80% have disappeared, the disturbing results crushed the researchers.

Insects are a fundamental foundation to the planet’s food chain. Experts say a crash in insect populations would likely lead to total ecological collapse.

The collapse isn’t just happening in Puerto Rico, all around the planet these most foundational elements of our global life support system are vanishing.  Flying insects in German nature reserves have dropped 75% in the last 25 years.

Birds have vanished from Australian eucalyptus forests, most likely from a lack of insects brought on by drought and heat waves. Researchers Brad Lister and his colleague Andrés García have also found that insect populations in one dry forest in Mexico have plummeted 80% since the 80s.

In Puerto Rico, animals that rely on insects in the rainforest have also declined. Frogs and birds have declined by around 50%. The Puerto Rican tody, a green bird that eats almost nothing but insects, has had its population plunge by 90%.

Researchers believe global warming is responsible for the insect population collapse in Puerto Rico. The rainforests do not face the same factors important elsewhere in the world, like habitat destruction and pesticide use, it has been a protected area for a long time.

As researchers looked for causes they found that the number of days with temperatures above 29 Celsius, have increased from zero in the 1970s to more than 40% of the days now.

There are very few studies of insect numbers over the past decades to serve as baselines for ongoing research into the destruction of the planet’s insects.



Photo: “Puerto Rico (Vega Alta cerro gordo)” by Ricardo Mangual is licensed under CC BY 2.0