Pesticides are threatening the lives of bees

Pesticide use has been at an all-time low since the early 1990s, and while many animals have benefitted from this, the increased potency has been detrimental to others. 

The chemicals used in pesticides that were harmful to vertebrates were removed from the formula and replaced by chemicals less toxic to them. However, as pesticides became more specialised, they became hazardous to organisms like aquatic invertebrates and pollinators. A recent study counting the harmful effects of an important pesticide on the species of solitary bee's ability to reproduce introduces mounting evidence that these organisms, which represent the vast majority of bees, are susceptible to the chemicals similar to their more socioeconomic equivalents. 

The research suggests that pesticide damage can compound over several generations, which might hasten the extinction of species that are essential for pollinating farmland and ecosystems. The research shows that bees can have significant and serious consequences from prolonged exposure to pesticides. 

How Are These Pesticides Harming Bees? 

One specific insecticide is the most insidious among all the kinds that kill bees. It is sprayed on soil or sprayed on seeds as neonicotinoid pesticides. After that, they enter plant cells and ultimately manifest as nectar and pollen. 

This results in a chemical disruption of the ability of learning and memory in honey bees, and solitary bees also experience the same consequence. At larger concentrations, the chemicals interfere with reproduction, for example, by lowering the survival of sperm, which results in fewer offspring, and therefore, the effects of neonicotinoids can last through the entire lifecycle of these essential pollinators. These findings were later put to further tests by ecologist Neil William and PhD student Clara Stuligross to confirm the detrimental effects and how the pesticides have been impacting bees. 

Extensive Research on Bees 

They decided to observe the lone blue orchard bee species, indigenous to the North American region and often used for the pollination of fruit trees like almonds and others. Three species of wildflowers were cultivated in 16 cages, each of which was approximately the equivalent of two compact vehicles, to provide food for the bees. Neonicotinoids were applied to the ground in 50% of the cages, just like farm owners apply this typical pesticide. The 16 male bees that were housed alongside the 8 female bees within every cage had access to nesting material (drilled holes in wood) and mud, which pollinators use to build cells for their offspring within the holes. This is why they're also known as mason bees, which is a trait shared by other solitary pollinators. 

After mating, the females placed their eggs within the holes, giving each one a lump of nectar and pollen and enclosing them in separate mud chambers. The females also were eating nectar and pollen that had been tainted with pesticides. In particular, they appeared slow and took longer to locate their holes, and they also produced fewer eggs as compared to normal bees. They simply appeared to be unwell, 

Blue orchard bee adults usually only have a short lifespan of several days. After they pass away, their offspring grow while consuming the nourishment that was left behind. Pesticide exposure causes long-lasting damage. Compared to honeybees that grew up without pesticides, honeybees that had ingested neonicotinoids had 30% less progeny. 

The soil was soaked in certain cages once more the following year to determine the impact of prolonged exposure. Consequently, fertility decreased. The study showed that those bees under continuous exposure to the pesticide, first as a larva and then as an adult, produced over 20% fewer offspring as compared to those honeybees, which were only exposed as a larva. 

The reduction in bee fertility adds up at an alarming rate - In comparison to bees that were never subjected to neonicotinoids, there would be around 75% fewer offspring. This rate is distressing, especially considering that bees in the real world are not protected and have access to an endless supply of food, such a decrease in fertility could cause colonies to experience a sharp decline. 

In Conclusion 

This research has given important insights into the global decline in the bee population. It is high time that government authorities take into account the harm that pesticides are causing to essential pollinators of the ecosystem.