In a Biodiversity Hotspot, Park Rangers Employ Butterflies To Assess Temperature of the Globe

Biologists have observed a troubling fall in insect abundance over the last decade, which some belief may herald the end of the arthropod apocalypse.

These studies, however, are mostly focused on temperate zones, leaving the tropics, which are home to the great majority of insect species, virtually unexplored.

In new research, biologists enlist the help of park rangers in Ecuador's Yasuni National Park, one of the world's most biodiverse environments, to analyze changes in insect abundance.

Plummeting number of insects

Last February 2019 from The Guardian, with the first worldwide scientific analysis, the world's insects are on the verge of extinction, risking a "catastrophic breakdown of nature's ecosystems."

According to the study, more than 40% of bug species are falling, and one-third are endangered. Extinction rates are eight times quicker than those of mammals, birds, and reptiles.

According to the best-known statistics, the total mass of insects is decreasing at a rate of 2.5 percent every year, implying that they may go extinct within a century.

The Earth is on the verge of its sixth mass extinction, with massive losses already observed in bigger creatures that are simpler to examine.

Insects, on the other hand, are by far the most diverse and plentiful creatures, outweighing humans by 17 times.

The new study chose the 73 greatest research done so far to estimate insect loss. Butterflies and moths have been particularly hard damaged.

Between 2000 and 2009, for example, the number of common butterfly species declined by 58 percent on agricultural land in England.

The UK has had the highest reported insect declines overall, albeit this is likely because it has been examined more intensively than most other areas.

Read more: Beatles, Butterflies Population Thriving While Some Insects Decline in Numbers

Building alternatives to save biology from its risks

(Photo : ROSLAN RAHMAN/AFP via Getty Images)

According to lead author Maria Checa, a research scientist at the Pontifical Catholic University of Ecuador and a former doctoral student at the Florida Museum of Natural History, "such an analysis has obvious benefits for scientific knowledge and conservation, but it was also important that it included social benefits for the people we worked with," as per ScienceDaily.

They still understand very little about the effects of climate change in tropical places because there aren't enough researchers with the skills to examine these areas, she says.

Because local actors are crucial stakeholders in conservation, researchers must provide them with this information.

Conservation scientists sometimes encounter a stumbling hurdle early in their careers: the bulk of the world's biodiversity is unevenly distributed in the tropics, yet the majority of experts who study it largely dwell in temperate regions.

As a result, many industrialized nations' flora and fauna are reasonably well-studied and benefit from large monitoring programs, such as Germany's decades-long study of insect decreases.

In 1976, the United Kingdom established a similar initiative that used butterflies as a proxy for the health of insect ecosystems, and it has subsequently been replicated by at least 19 additional European nations.

These continuous surveys give scientists a plethora of data, but the patterns they uncover represent just a sliver of the worldwide changes that are taking place.

"In the United Kingdom, there are less than 60 butterfly species, but in Yasuni, there are possibly more than 1,500," said senior author Keith Willmott, collector and chairman of the Florida Museum's McGuire Center for Lepidoptera and Biodiversity.

Even with the assistance of forest rangers, it is impossible to sample the richness of a full rainforest. Instead, scientists rely on indicator species, which are creatures that are widely spread and simple to discover yet are sensitive enough to environmental change to be used to infer how closely related groups are faring.

The rangers rapidly learned how to gather butterflies with bait traps and identify the most frequent species while working with Checa, Willmott, co-author Sofia Nogales from Ecuador's National Institute of Biodiversity, and their colleagues.

They've been doing frequent surveys since 2017, with accuracy rates equivalent to those of expert field biologists. Their contribution to the study, however, did not stop there.

The rangers desired to be more engaged in the process, so Checa and I started discussing drafting a text together.

In Quito, researchers organized a session in which they brought computers and trained participants on how to do basic statistical analysis on butterfly data.

Related article: Butterflies Consume Live Young to Increase Supply of Mating Pheromones