Brunette Gardens

A leafcutter bee drawn to a borage flower.

By Lisa Brunette

Last year was a lot of things that weren't good, but one silver lining for me was that it was also the year of the bee.

You might remember I signed up for Shutterbee, a joint citizen science program sponsored by my alma mater Saint Louis University's Billiken Bee Lab, Webster University, Missouri Botanical Garden, and the Saint Louis Zoo. Through the volunteer program, participants at 165 homes tracked and photographed bees in our backyards using a set scientific protocol, uploading our findings to iNaturalist for cataloguing and further study. The goal of the program overall is to "understand how landscape features and land management decisions affect bee diversity and behavior," according to researcher Dr. Nicole Miller-Struttman. The bee scientists running the study are also trying to determine whether or not citizen photographic surveys could take the place of the tried-and-true practice of surveying bees through net collection.

Here's what one of the uploaded bee records looks like, with the following elements included: bee photo, an "Sbee" tag to identify the entry to program researchers, the length of my survey (30 minutes), and the name of the plant the bee was foraging.

The results of this year's study? 

• I myself completed 8 observation rounds, following the protocol to survey our garden about every two weeks over three months in the summer. I catalogued a total of 73 bees across 22 different species. 
• The Shutterbee participants as a whole spotted 8,309 bees across 83 different species during the 2020 survey.
• The program's all-time total is 10,878 spottings across 83 species.

While I did spot a number of non-native Western honeybees, aka Apis mellifera, especially in the beginning when I was still learning to differentiate, the vast majority of my finds were native bees. This is important because 87 percent of flowering plants depend on creatures for pollination, many of them having evolved together, like the orchid and the orchid bee. We absolutely depend on native bees for our food supply, too. One example is the squash bee, which pollinates squashes and other edible plants in the same family, such as cucumbers. These two species also evolved together. Some common bee names give you a hint about the interrelationship between the bee and the flowers it pollinates, such as the hibiscus turret bee and the morning glory turret bee. I spotted both in our garden, and we grow both flowers that are their namesakes.

HIbiscus turret bee, or Ptilothrix bombiformis, on our native hibiscus.

Though this is Melitoma taurea, or Morning glory turret bee, here it's also enjoying the hibiscus flower.

My most exciting find? The American bumblebee, Bombus pensylvanicus, a threatened species that was once numerous but is now in serious decline: by 98 percent since the 1990s, according to a presentation given by Shutterbee researcher Emily Buehrle. The decline is due to a host of factors, from the overuse of pesticides to habitat loss and the effects of climate change. We have a lot of sunflowers, which is this bee's favorite food, but I photographed it on a native plant called Lobelia siphilitica, or blue lobelia. For me, this is heartening, as I don't know that we'd have had this rare bee sighting back when our yard consisted of nothing but turf grass and non-native, invasive plants.

American bumblebee, which is listed under threatened status.

Another singular bumblebee spotting for me was the native Bombus griseocollis, or Brown-belted bumblebee, which showed up one day in June to gather nectar from the native hydrangea then in full bloom.

Bombus griseocollis, or Brown-belted bumblee, on native hydrangea.

I also had just one chance to capture the Bicolored striped sweat bee. The glimpse of its metallic green thorax gave me quite a thrill when I spotted it on a sunflower in early August.

Bicolored striped sweat bee, or Agapostemon virescens, on a sunflower.

The most commonly spotted bee in our garden last year was the Eastern carpenter bee, or Xylocopa viriginica, a native bee that is a good pollinator for blueberries as well as a wide range of native plants. It's a large, easy bee to spot, resembling a bumble bee in its sound and sight, with a signature black dot on the thorax surrounded by yellow fuzz.  

Eastern carpenter bee, Xylocopa virginica, on native swamp milkweed.

Of note is the frequency with which I spotted the Modest masked bee. This tiny bee visited a native plant that is a bit of a conversation piece itself, Rattlesnake master, or Erygnium yuccifolium, which blooms with spectacular white pom-pon flowerheads.

Modest masked bee, Hylaeus modestus, on native Rattlesnake master.

My favorite bee, though? That would be the Eucerini, or long-horned bee. I was treated to their sight pretty much all summer, as they love the same plucky flowers I do, the sunflowers, of course, and the brown-eyed Susans. They brightened my day with those crazy long antennae, moving with a sense of frenetic urgency as they become doused in pollen. They make me smile.

Rudbekia hirta, a North American native, is a popular foraging plant for this long-horned bee in the tribe Eucerini.

The preliminary study results from this past year were a bit surprising, as they suggest that the non-native Western honeybees are taking advantage of more diverse flower gardens by broadening their foraging; whereas, four large native bees pulled out for comparative analysis are not changing their behavior. However, there was some boost for areas with fewer impervious surfaces, earth instead of asphalt. Shutterbee is a multi-year program, and more data is needed to assess both the impacts of conservation efforts on bee population and foraging behavior and the ultimate efficacy of citizen science data collection. I look forward to participating again this year.