Bees in trees

Bees are responsible for the production of approximately one-third of the food we eat. Accordingly, their decline has received attention in the media as well as in conservation biology. While the honey bee (Apis mellifera) is the species most people are familiar with, there are over 400 bee species native to New England. The honey bee, however, is not a native species (Europeans brought them over here!) and not actually of conservation concern. Although it is more difficult to manage honey bees than it was in the past, and large honey bee colonies are essential for current commercial pollination practices, honey bees are doing just fine relative to our declining native species.

Since 2020, my lab has identified over twenty bee species on the Providence College campus alone, including the rare golden Northern bumble bee (Bombus fervidus). Most sampling/surveying methods, however, only focus on bees at the ground-level. Bees obtain food from flowers and here in New England, trees offer some of the few early spring blooms. Despite this, there is only one published study on bees collected/observed in trees. Aidan Castricone (UG ’24), a student in my lab, is using a pulley system to set traps (i.e., painted Solo cups) to survey “bees in trees” to compare diversity among habitat types at Gavins Pond (Foxborough, MA) and to determine diversity of bees in pollinator-friendly, spring blooming trees on the Providence College campus (Providence, RI) . The brightly colored cups attract bees, which then fall into a soapy water solution and unfortunately, drown. We then collect the bees, pin them, and identify them in the lab. Check out the video of Aidan at work here!

My lab is using this lethal method of sampling to create both physical and digital reference collections of local insect pollinators. This reference collection will aid in future studies of bees and what they eat, without lethal trapping.

Want to save the bees?

Keeping honey bees is not going to save the bees. In fact, adding more non-native honey bees to the environment may actually be harmful to our native bees. Here are three things you can do to save the bees (and other pollinators, like butterflies).

1. Plant native, blooming tress, shrubs, and wildflowers.

Diverse bloom colors, shapes, and sizes will ensure you’re providing food for diverse pollinators: bees, butterflies, hummingbirds, etc. It’s also helpful to plant flowers with a range of bloom times. This will ensure pollinators have food throughout the season. And finally, planting native is better for both you and the pollinators! Native plants are adapted to the local environment, meaning they need less upkeep on your end. They also have long-standing relationships with, and are accessible to, our local pollinators. You can find more information on what to plant in the Northeastern US from the Tufts Pollinator Initiative. The Pollinator Partnership has fantastic eco-regional planting guides for other areas/habitat types in the US and Canada.

2. Avoid chemicals.

Insecticides do not just affect pest insects, they affect pollinating insects (and other wildlife!) as well. It is especially important to avoid a certain type of systemic insecticides, called neonicotinoids. If using herbicides to kill weeds, like dandelions, remember that weeds flower too! Dandelions, clover, and other small flowering weeds are important early spring food sources for pollinators.

3. Do less yard work!

A green lawn with no flowers or habitat does not support pollinators. The “lazy lawnmower” approach (i.e., mowing less frequently) dramatically increases biodiversity of both flowers and pollinators. If you’re not into an unmown lawn, supplement your lawn with gardens along borders, in raised beds, or even in containers. In the fall, leaves and woody stems provide habitat for butterflies, solitary bees, and more! So give yourself a break, and #leavetheleaves.