Many individuals reminisce about summer evenings filled with moths and mayflies swarming around porch lights or road trips marked by windshields covered in insect splatters. Some may have a sense that things have shifted.
Researchers confirm these recollections reflect a tangible reality: the declining abundance of insects in Canada and globally, impacting birds, bats, fish, plants, and humans.
In southern Ontario, Hadil Elsayed, a PhD student at York University, discovered a significant decrease in the total insect mass collected at two protected sites by around half since the 1990s. A citizen-science initiative in the U.K. observed a sharp decline in flying insects by tracking insect splatter on license plates. Numerous studies from around the world also highlight insect population declines.
During the summers from 2021 to 2023, Elsayed meticulously trapped insects to assess populations at Long Point National Wildlife Area and St. Williams Conservation Reserve in southern Ontario, replicating a survey conducted by Environment Canada in the early 1990s. Although her findings have not yet undergone peer review, they indicate a nearly 50% reduction in the total trapped insect mass over the past three decades.
The decline primarily affected minuscule flies known as midges, crucial as a food source for various wildlife. Elsayed’s research revealed a loss equivalent to approximately 640 million midges, emphasizing the magnitude of the decline.
The study aligns with research from the University of Michigan and Birds Canada, indicating a substantial drop in flying insects at Long Point Bird Observatory. Flies, including midges and mosquitoes, showed the most significant decline, with decreases also noted in butterflies and beetles.
Conservationist Andrew Whitehouse emphasized that the decline of common insect species might be more concerning than rare species’ extinction, as common insects play vital roles in ecosystem functions like pollination and decomposition.
Insect declines have far-reaching implications, impacting species like insect-eating swallows, which are shrinking in numbers due to diminishing food sources. Insects are essential for pollination, pest control, and sustaining the food chain, affecting humans, animals, and plants.
Experts attribute insect declines to various factors, including habitat loss, invasive species, pesticides, pollutants, and climate change. Reversing these declines is possible through actions like planting native vegetation, habitat preservation, and reduced pesticide use.
Despite the challenges, Elsayed and Whitehouse remain optimistic that concerted efforts can restore insect populations. Creating connected natural habitats is crucial for protecting insects and preserving biodiversity.
Insects not only serve ecological functions but also offer a unique perspective on nature firsthand. Elsayed and Whitehouse urge collective action to safeguard insect populations and the ecosystems they support.
