The first scenes to come to mind for many of us when we read ‘apex predator’ are megafauna hunting across vast expanses (in a documentary narrated by Sir David Attenborough) – Lions and Leopards of Africa, Gray Wolves of the Yellowstone Basin, Brown\Grizzly bears of Alaska, or Orcas of the Pacific Northwest coast.
Let’s face it, we are drawn to big, gory, gruesome. When we are safely on our couches in our urban\suburban houses. We can watch it, but it is distant and the goriness of the sights, sounds, and smells are diluted because these episodes are not front and center in our everyday lives. The narrator is always adept at placing the ‘killing’ in the context that it is a natural part of nature’s ongoing sustainability cycle and natural balancing act. We are assured that apex predators provide vital, almost noble, environmental services. We experience of the circle of life that exists outside our lives. (As opposed to the nightly news of mass murders)
What can be missed while consuming these documentaries streamed to our wide-screen TVs is these very same ‘noble’ acts in the circle of life go on in our yards. Apex predators live right outside our windows providing critical environmental services maintaining balance and preventing our yards from being overrun by ‘pests’. Or, at least, they try to.
Our relationship with predators in our real lives is not ‘noble’ for either the predators or us for at least a couple of reasons. Perhaps one is an instinctive, often overwrought, fear that we are the quintennial prey tucked deep in the evolutionary archives of our brain stems. Nature is a dangerous place where we can be attacked and eaten at any moment, but particularly at night. For some of us, especially those that still live and work in proximity with nature, there is the belief, often unfounded, that predators are economic competitors. Predators raid pastures and chicken coups and eat our grains bringing financial ruin. They attack and eat the ‘cuties’. They carry away our pets. Even our children. Or so we believe.
Pictures of this young Red-shouldered Hawk posted on our neighborhood association Listserv brought out questions from otherwise friendly, caring, welcoming, ‘green’ neighbors, of how to control this disturbing interloper and protect the Lost Cats that are the topic of many posts. My answer is they provide valuable ‘pest control’ and our pets over the size of 2.5 pounds are safe (if they are under 2.5 pounds hawks may be the least of their problems). But, unfortunately, these well-intentioned neighbors may get their wish indirectly and through a process we are being sold as a good thing to do – the use of chemical substances to control ‘pests’. Which are in fact the predators prey that for millenia they have controlled. In this case a specific class of pesticide, rodenticides.
Why is this happening? It is our response to predators in our midst. We do our best to make them, at a minimum, unwelcome in the habitats we share. At our most efficient selves we wholesale remove them from the ecosystems they balance. We put bounties on their heads.
This is not limited to megafauna. We move down the food web eventually taking in insectivores and herbivores of all sizes and taxonomic families. The result? The ecosystems are overrun by the next most despised species category the annoying ‘pests’. A trophic cascade is set off. A top-down trophic cascade is when the removal of the top predator alters the food web dynamics, typically detrimentally. The primary consumers overpopulate and exploit the primary producers. Eventually there are not enough primary producers to sustain the consumer population. Biodiversity shrinks or collapses altogether.
Our response? We counter with ‘science’. To be specific, chemistry. To be more specific, we turn to pesticides: “chemical substances used to prevent, destroy, repel or mitigate any pest ranging from insects (i.e., insecticides), rodents (i.e., rodenticides) and weeds (herbicides) to microorganisms (i.e., algicides, fungicides or bactericides)”. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2946087/)
As is our nature we go all-in. In agriculture, more than 1,000 pesticides, 5.6 billion pounds per year, are used around the world to ensure food is not damaged or destroyed by pests. Many of these pesticides are also used in our yards and public spaces to protect manicure lawns and ornamentals.
These pesticides do not honor the boundaries of the fields, pastures, lawns, gardens, and landscaping: “Although attempts to reduce pesticide use through organic agricultural practices and the use of other technologies to control pests continue, exposure to pesticides occupationally, through home and garden use, through termite control or indirectly through spray drifts and through residues in household dust, and in food and water are common. The US Department of Agriculture has estimated that 50 million people in the United States obtain their drinking water from groundwater that is potentially contaminated by pesticides and other agricultural chemicals. Children from 3-6 years old received most of their dermal and non-dietary oral doses from playing with toys and while playing on carpets which contributed the largest portion of their exposure.” (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2946087/)
The CDC estimates that 90% of us have detectable concentrations of pesticide biomarkers in our urine or blood. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5734986/)
We are of course not alone in pesticide exposure. Natural predators of the very pests we are targeting, our allies and friends, also consume large amounts of the pesticides leading to further declines in their populations in turn leading to fewer checks on the pests leading to sharp declines in the biodiversity of ecosystems. Except, ironically, for the pests. It seems that our brain stems will not allow us to fully comprehend that the ‘enemy of our enemy is our friend’ and not to be feared.
We also cannot seem to comprehend the total economics of healthy biodiverse ecosystems with predator-lead checks and balances. Yes, the agriculture industry might save dollars from lower livestock loss or not lose as much market value of grain, but there is a cost, and its growing, of the healthcare for and the lost productivity from exposure to overuse, especially of known highly toxic substances. For example, in the US, 1 billion pounds of 400 different pesticides, 150 of which are banned in different countries around the world, are routinely used to combat pests.
To be clear, I am not calling for the banning of pesticides. I am calling for moderation and balance. One approach that deserves consideration is Integrated Pest Management (IPM) developed by the National Pesticide Information Center: http://npic.orst.edu/pest/ipm.html
– Hid