Why pollinators need our gardens

Invertebrate populations have been declining dramatically, a phenomenon dubbed ‘insectageddon’ in the media. Why insect populations are plummeting–and why it matters, an article by National Geographic, provides a good summary of this issue. These losses are world-wide, as shown in recent studies of German parks and Puerto Rican tropical forests.

The ‘windshield phenomenon’ illustrates the visible decline in insects closer to home. Do you remember from your childhood, so many insects hitting car windshields at night that your parents had to stop to clean them off? Now you will hardly see any.

That might sound great because fewer bugs means fewer mosquitoes and black flies. However, insects pollinate many of our food crops, as well as wild plants, and are essential food for birds and other creatures. They are a foundation of food webs and without them other life on Earth is threatened. That may sound overly dramatic, but it’s true and scary.

Major causes of declining insect populations include habitat loss, pesticide use, and climate change.

Habitat loss, a leading cause

I used to think that habitat loss was just an American problem. After all, Canada has a relatively small population, and a lot of wilderness. However, in southern Ontario most wild spaces have been cut, bull-dozed, plowed and paved. A Government of Ontario page on Conserving Biodiversity lists habitat loss as a serious threat to wildlife in our province. According to Tallgrass Ontario, less than 3% of Ontario’s tall grass prairie remains. Ontario Nature states that only 30% of Ontario’s original wetlands remain.

Eliminating habitat means that insects have less food and fewer places to live. Some pollinators that once called southern Ontario home, like the Rusty-Patch bumblebee and Karner Blue butterfly, are no longer found in this province. Habitat loss is considered the main cause of their disappearance. You can learn about these pollinators, and efforts to restore their populations at Wildlife Preservation Canada. Recent news stories, from the CBC and GuelphToday, highlight that the American Bumblebee is similarly at risk in Ontario.

Our remaining wild spaces are continually being chipped away, further threatening native pollinators and other wildlife. The Ontario Nature web site is a good place to keep up with current news and their efforts to combat habitat loss.

Pollinator ‘victory gardens’

Urban dwellers can help compensate for habitat loss by providing pollinators, and other insects and wildlife, with chemical-free gardens using native plants. If many people create pollinator gardens, they will add up to significant areas of habitat and connect patches of existing habitat. Read “More urban gardens encouraged to help save bees” at GlobalNews, and “Urban Refuge: How Cities Can Help Rebuild Declining Bee Populations” at the YaleEnvironment360 web site for more information.

With wartime ‘victory gardens’, many Canadians grew their own food so crops could be diverted to feed our troops and struggling allies. So many people participated that their gardens had a significant impact. Now, pollinator victory gardens can have similar impact. You can learn about this movement in EcoBeneficial’s The Pollinator Victory Garden video, and in the book Victory Garden for Bees by Lori Weidenhammer (available at the Ottawa Public Library). I saw this idea in practice on a 2018 summer-time vacation in Toronto. In the neighbourhood where we stayed, many home-owners had planted their postage-stamp-sized front yards with native plants. Side-by-side, the yards equaled a street-long habitat where we saw many bumblebees and Monarchs.

This isn’t a perfect solution. A few recent studies have shown that cities cause some unexpected issues for native bees. Mitigating the Effects of Heat on Urban Pollinators investigates the ‘urban heat island’ effect on bees. In my own garden, I observe few bumblebees on extremely hot days. The Impact of urbanization on wild bees underestimated describes that there are more male ground-nesting bees than females in cities. It takes more pollen, and higher protein pollen, to rear female bees, so perhaps planting more native flowers with high-quality resources will help correct that imbalance. Ideally, it would be best to preserve and restore wilderness for native species. While urban pollinator gardens won’t solve the problem of declining insect populations, whatever we can do to help is better than nothing.

You can do it too!

With my pollinator garden, I really feel like I am making a difference. It may be a small difference, but it is a tangible one. I can see right in front of me that I’m now providing food and shelter for hundreds of bees and butterflies, and dozens of birds. I would never have imagined that my new pollinator garden would be so full of life.

If more people, like you, turn some unused lawn into a pollinator garden, the impact of these gardens will add up. Plant it and they will come; it really is that simple. My garden is living proof. Go ahead, you can do it too!