The United States Environmental Protection Agency (EPA) has published alarming analyses on The effects of three common pesticides—chlorpyrifos, diazinon and malathion—on endangered species. Studies show how these chemicals affect not only the animals, but also the critical habitats in which they live.
The results are shocking: the pesticides chlorpyrifos and malathion have a negative impact on a 97% of species protected under the Endangered Species Act, while Diazinon affects 79%. This includes a wide variety of fauna and flora, from birds to insects, amphibians, reptiles and endemic plants.
The consequences are especially dire for animals that rely on very specific habitats, such as wetlands. Many of these pesticides are commonly used in agriculture and pest control, leaving these species in a critical situation.
Use and applications of pesticides
Malathion is widely used in agriculture to treat fruits and vegetables, as well as ornamental plants. It is also frequently used in Tick ​​control in petsChlorpyrifos, on the other hand, is used to control termites, mosquitoes, ants and worms, although recent research has shown that the negative effects of these products go far beyond their initial objectives. Diazinon, intended for the extermination of cockroaches and ants, also poses similar risks.
The extensive use of these chemicals affects various species directly and indirectly. Malathion and chlorpyrifos, for example, are especially harmful to pollinating insects, such as bees, but they also affect birds that feed on the contaminated insects. In fact, studies have shown that neonicotinoid insecticides, such as chlorpyrifos, are one of the main culprits of the catastrophic decline in insect populations worldwide.
For the first time in history, we finally have data showing just how catastrophic these pesticides are for endangered species, from birds and frogs to fish and plants. – Lori Ann Burd, Center for Biological Diversity.
The long-term impact on the ecosystem
Pesticides not only have immediate effects on the target species, but also have long-term effects on the entire ecosystem. One of the most worrying effects is the bioaccumulation of these substances in the food chain. This means that pesticides, once applied, do not disappear quickly. Even when insects or rodents die from poisoning, the predators that consume these animals are also affected, developing chronic diseases or reproductive failures.
A clear example of this phenomenon is the study of the birds of Doñana, where many species of birds of prey, such as the Booted Eagle and Black Kite, show worrying levels of pesticides such as DDT, despite having been banned for decades. This organochlorine compound, along with other current pesticides such as pyrethroids, affects the hatching of eggs and the survival of chicks.
Habitat destruction and ecosystem pollution critically affect global biodiversity. Doñana National Park is a clear example of how pesticide pollution from nearby agricultural activities is endangering its unique biological diversity, affecting more than 100,000 inhabitants. 350 bird species and other protected species.
The case of pollinating insects
A group of species particularly affected by pesticides are pollinating insects such as bees, butterflies and other insects that play a crucial role in pollinating food crops. Recent studies have shown that more than 40% of insect species are threatened with extinction due to pesticide use and habitat loss. This is especially alarming because many of these species are vital to agriculture and maintaining healthy ecosystems.
The case of the monarch butterfly is another emblematic example. The use of herbicides such as glyphosate has devastated its main food source, milkweed, leading to a decline of more than 80% of the population of this species in just two decades. In addition, the introduction of herbicide-resistant crops has allowed glyphosate to be sprayed in large quantities, exacerbating the problem by destroying key habitats for the caterpillars of this butterfly.
The fundamental role of bees
Bees are one of the most important pollinators in the world. Their decline due to the use of pesticides such as neonicotinoids puts agricultural ecosystems at risk. FAO studies estimate that more than 100 million bees are dying. 84% of crops intended for human consumption depend on pollinating insects. Among them, bees play a crucial role for plants such as apples, strawberries and almonds, among others.
Pesticides can affect bees in a variety of ways. Some research shows how even small amounts of these chemicals interfere with their neurological systems, affecting their ability to navigate and collect nectar, eventually leading to Colony Collapse, a devastating phenomenon that has contributed to the collapse of entire colonies in many countries.
El intensive use of pesticides Not only does it affect bees and other pollinating insects, but it also has the effect of disrupting food chains, which can lead to a domino effect of species extinction. It is therefore essential to reduce the use of pesticides and look for more sustainable alternatives.
The path to sustainable solutions
While the current outlook is alarming, there are sustainable alternatives that can mitigate the effects of pesticides without compromising agricultural productivity. Integrated Pest Management (IPM) is one of the most promising solutions. This approach focuses on combining biological, cultural and physical techniques to reduce dependence on chemical pesticides.
An example of how MIP can be effective is the use of crop rotations and the use of beneficial insects to control pests. Crop rotations improve soil health and reduce the likelihood of pests, while beneficial insects can serve as natural predators of species typically controlled with chemical pesticides.
Furthermore, the ban on certain pesticides in the European Union has proven to be effective in protecting key pollinator species such as bees. However, this ban must be accompanied by global measures to curb the excessive use of pesticides worldwide.
Ultimately, the Reducing pesticide use and implementing more sustainable agricultural technologies would not only help preserve endangered species, but would ensure the long-term health of the ecosystems on which we all depend.