INSECT POPULATION DECLINE

Feb. 24, 2019

According to the first global scientific review, published in the journal Biological Conservation, the world’s insects are going down the path to extinction, threatening a “catastrophic collapse of nature’s ecosystems”.

About: 

  • More than 40% of insect species are declining and a third are endangered. The total mass of insects is falling by a 2.5% a year suggesting they could vanish within a century. 

  • The rate of extinction is eight times faster than that of mammals, birds and reptiles. 41% of global insect species have declined over the past decade compared with 22% of vertebrate species. 

  • Insect population collapses have recently been reported in Germany and Puerto Rico, but the review strongly indicates the crisis is global. In Puerto Rico a recent study revealed a 98% fall in ground insects over 35 years. 

  • Butterflies and moths are among the worst hit. For example, the number of widespread butterfly species fell by 58% on farmed land in England between 2000 and 2009. 

  • Factors: Intensive agriculture is the main driver of the declines, particularly the heavy use of pesticides. Urbanisation and climate change are also significant factors.  

  • Impact: Insects are by far the most varied and abundant animals, outweighing humanity by 17 times. They are “essential” for the proper functioning of all ecosystems as food for other creatures, pollinators and recyclers of nutrients. One of the biggest impacts of insect loss is on the many birds, reptiles, amphibians and fish that eat insects. 

  • Comment: The insect trends confirm that the sixth major extinction event is profoundly impacting on life forms on our planet. The planet is at the start of a sixth mass extinction in its history, with huge losses already reported in larger animals that are easier to study.