The topic and overall use of pesticides, insecticides and avicides may seen a confusing one, but the consequences and environmental fallout from the application of these toxins is anything but.
Insecticides, namely neonicotinoid pesticides, were first shown to have serious and devastating effects on pollinators before later being linked to the decline in songbird populations. Through the recent research conducted at the University of Saskatchewan by expert ecotoxicologist Dr. Christy Morrissey and post-doctoral fellow, Dr. Margaret Eng, has indicated significant neurological and physiological effects of insecticides on local songbirds populations, resulting from their application on agricultural land. These effects include rapid weight loss in bird species as a result of decreased appetite and increased fatigue, resulting in a drastic decline in various bird populations dependent on the insect populations surrounding agricultural settings. While not the main target for the application of insecticides, songbirds that rely on these insects that producers look to destroy, end up being adversely affected by these same products.
A prime example of secondary poisoning, insecticides pose a serious threat to local biodiversity, ranging from the insects they target, to avian predators, and further other mammalian species that are dependent on the organisms being affected by these poisons.
While this issue may seem removed from present society and appear as though nothing can be done at the individual level, it is far closer to home than some may think.
In Saskatoon, Saskatchewan, the battle against avicides has gone on for years. Jan Shadick, the executive director at Living Sky Wildlife Rehabilitation in Saskatoon, has taken the battle upon her shoulders to lead the fight against the use of avicides for several years and has been met with much resistance from the City of Saskatoon and a local pest control company. Despite the chemical being deemed a nervous system poison by the Human Society of the United States, and the use ultimately banned in various provinces around Canada, the resistance to change their ways in Saskatchewan, has presented serious complications for local wildlife.
Avitrol, the neurotoxin in question, results in seizures, convulsions and rapid neurological decline in the poisoned pigeons, but does not lead to a quick and painless death like supporters of the chemical believe. This poison, while intended for pigeons, the target species, does not only affect pigeons. Pigeons are part of the local ecosystem, and as such, are a part of the food chain. Similar to the damaging secondary poisoning effects that are seen through the use of insecticides on insects that are later consumed by songbirds, other local wildlife that finds these severely debilitated pigeons, or their carcasses, are at risk for consuming large amounts of the chemical and in turn, starts the process of bioaccumulation throughout the food chain. While the local pest control company stands by the knowledge that this chemical is not harmful and works efficiently, they claim there is no risk to local wildlife.
Bioaccumulation is the accumulation of chemical/toxin concentrations within a single organism, that results in greater concentrations of these chemicals found throughout the food chain the higher it goes. Secondary poisoning occurs through the ingestion of poisons through a secondary source that consumed the initial poison source, resulting in adverse effects on a non-target species. In the case of the poisoned pigeons, many wildlife species rely on pigeons as an easy food source in the surrounding Saskatoon areas. While the pigeons can often be found seizing on the side of the road, they do not always react to the poisoning right away, and often have flown a distance away from the site of poisoning, entering a different environment and passing away. It is this movement of the poison from one location to the next that creates extreme risk and concern for local wildlife especially those that eat pigeons. This includes the once-endangered Peregrine Falcon, scavengers like crows and magpies, other raptor species such as hawks and owls, foxes, and even domestic pets including cats and dogs.
This should hit close to home. It is not uncommon to find deceased birds in local settings including parks or nature trails, outside stores, or along the sidewalk - and these are all places we may choose to frequent with our furry friends. It is also not uncommon for cats and dogs to grab and eat these same birds in the blink of an eye or while our attention is elsewhere - and this is where the risk lies.
Whether or not the use of insecticides, pesticides and avicides serves a purpose for the goals set by these pest control companies or producers, effective and safe methods must be deployed when the ecosystems of these target species become at risk for exposure.
For more information, to add your voice to the fight against pesticides, or to find ways to help, check out the resources listed below. While it is not an exhaustive list of the many studies, news articles and relevant sites on these topics, they are a great place to start!
- Wildlife rehabilitation centre asking Saskatoon to ban use of neurotoxin on pigeons | CBC News
- Saskatoon woman says people may be using neurotoxin to poison local pigeons | CBC News
- How Pesticides Threaten Birds, Bees, and Other Wildlife — Neonicotinoids and Honeybee Decline | Audubon
- Impacts of Pesticides on Wildlife — Beyond Pesticides
- USask-led study shows insecticides threaten survival of wild birds - News - University of Saskatchewan
- 2 widely used pesticides toxic to songbirds: research - Saskatoon | Globalnews.ca
- Saskatchewan Network for Alternatives to Pesticides (SNAP) (snapinfo.ca)
- Update on Neonicotinoid Pesticides and Bee Health - Canada.ca