Sunday, while cutting up edited plants into my compost tumbler, I caught sight of something unusual out of the corner of my eye. It turned out to be Bombus fervidus, golden northern bumblebee, or simply, the yellow bumblebee.
This is at least the 21st bee species I’ve found in my garden. And this brings to 20, or more, the number of new insect species I’ve identified in my garden this year alone.
A leaf-cutter bee removes a segment from a leaf of Rhododendron viscosum, swamp azalea, in my urban backyard native plant garden and wildlife habitat (National Wildlife Federation Certified Wildlife Habitat #141,173). You can see other segments – both completed and interrupted – on the same and adjacent leaves.
Like carpenter bees, Leaf-cutters are solitary bees that outfit their nests in tunnels in wood. Unlike carpenter bees, they’re unable to chew out their own tunnels, and so rely on existing ones. This year, I’ve observed a large leaf-cutter – yet to be identified – reusing a tunnel bored in previous years by the large Eastern carpenter bee, Xylocopa virginica.
They use the leaf segments to line the tunnels. The leaves of every native woody plant in my garden has many of these arcs cut from the leaves. The sizes of the arcs range widely, from dine-sized down to pencil-points, reflecting the different sizes of the bee species responsible.
Tiny arcs cut from the leaves of Wisteria frutescens in my backyard.
I speculate that different species of bees associate with different species of plants in my gardens. The thickness and texture of the leaves, their moisture content, and their chemical composition must all play a part. I’ve yet to locate any research on this; research, that is, that’s not locked up behind a paywall by the scam that passes for most of scientific publishing.
Although I’ve observed the “damage” on leaves in my garden for years, this was the first time I witnessed the behavior. Even standing in the full sun, I got chills all over my body. I recognize now that the “bees with big green butts” I’ve seen flying around, but unable to observe closely, let alone capture in a photograph, have been leaf-cutter bees.
As a group, they’re most easily identified by another difference: they carry pollen on the underside of their abdomen. A bee that has pollen, or fuzzy hairs, there will be a leaf-cutter bee.
An unidentified Megachile, leaf-cutter bee, I found in my garden.
Another behavior I observe among the leaf-cutters in my garden is that they tend to hold their abdomens above the line of their body, rather than below, as with other bees. Perhaps this is a behavioral adaptation to protect the pollen they collect. In any case, when I see a “bee with a perky butt,” I know it’s a leaf-cutter bee.
When they’re not collecting leaves, they’re collecting pollen. Having patches of different plant species that bloom at different times of the year is crucial to providing a continuous supply of food for both the adults and their young.
An individual bee will visit different plant species (yes, I follow them to see what they’re doing). And different leaf-cutter species prefer different flowers. All the plants I’ve observed them visit share a common trait: they have tight clusters of flowers holding many small flowers; large, showy flowers hold no interest for the leaf-cutter bees.
Earlier this evening, I was interviewed on Sex and Politics Radio, a program broadcast on Brooklyn College Radio. If you missed it, the podcast will be published sometime next week.
Related Content
If you want to learn more about some of the issues I talked about on the radio tonight, take a look at some of my past blog posts about bees.
One of the great pleasures of gardening is observing the activity the garden invites. I can lay out the welcome mat, and set the table, but the guests decide whether or not the invitation is enticing enough to stop by for a drink, a meal, or to raise a family. While charismatic megafauna such as birds and mammals are entertaining, the most common and endlessly diverse visitors are insects.
The Hymenoptera includes bees, wasps, and ants. Although my garden also provides amply for ants, we’ll stick with the bees and wasps today. Following are some of the few portaits I’ve been able to capture of the many visitors to my gardens. The pollinator magnet, Pycnanthemum, Mountain-mint, in the Lamiaceae, provides the stage for many of these photos. I’m always amazed at the variety and abundance of insect activity it attracts when blooming.
Multiple pollinators on Pycnanthemum
Bees
There are over 250 species of bees native to New York City alone. I’m still learning to identify just a handful of the dozens of species that frequent my garden.
My current favorite is the bejeweled Agapostemon, Jade Bee Bombus impatiens, Common Eastern Bumblebee, on Monarda fistulosa
Coelioxys, Cuckoo Bee. I think I’ve got several species from the genus visiting my garden, but I’ve yet to get identification for the others. These are in the Megachilidae, the Leaf-cutter and Mason Bee family. Bees in this family typically carry pollen on hairs beneath their abdomens, instead of in pollen baskets on their legs. You can see this bee isn’t carrying any pollen; it doesn’t even have the hairs beneath its abdomen to do so. It doesn’t need to, because it takes over the pollen-provisioned nests of other leaf-cutter bees for its own young.
Along with the Hymenoptera come the mimic flies. Many of the seeming bees and wasps, seen from a distance, turn out to be flies on closer inspection. In “the field,” i.e.: my garden, there are two features that provide quick distinction between the two familes:
Antennae: Flies have short, clublike antenna, like feelers, in the center of the face, between the eyes. Bees and wasps have long, segmented antenna arising higher up on the face, almost from the top of the head
Eyes: Flies’ compound eyes are huge, covering nearly all of their face. Bees and wasps have compound eyes that wrap partially along the sides of their heads.
The feet are also different, but I usually don’t notice those until I’m browsing and culling my shots. Finally, bees and wasps have four wings, while flies only have two – Di-ptera, two-winged.
The Syrphidae/Flower-Fly family hosts countless mimics of bees and wasps.
Eristalis arbustorum on Hydrangea
Eristalis transversa, Transverse Flower Fly
Their tactics of mimicry are not limited to patterns and colors. Many species have evolved body modifications to mimic even the shapes of wasps and bees.
Syritta pipiens provides a good example of this. This is the most wasp-like fly I’ve found yet in my garden, though more extreme mimics exist. Glimpsed from behind as it moves quickly over the flowers, it could easily be mistaken for a tiny wasp.
Viewed from the side, or the front, Syritta is more obviously a fly, not a wasp, and a dedicated mimic.
Toxomerus geminatus sports a radically flattened abdomen. This seems to be an adaptation to present a wider area from above, as a predator might view it, for displaying its mimicry, while preserving a smaller volume and keeping weight down.
I wonder what they are mimicing? Might some of these mimics mirror actual target species, not just general “bee-ness” or “wasp-ness”? If so, I would expect to find both the mimic and subject in the same range, and exhibit the same phenology. For example, Toxomerus bears a resemblance to Agapostemon at a quick glance.
Photographing Insect Activity
This is my setup for doing live insect macro photography “in the wild,” i.e.: in my garden. The lens is a specialized macro lens that allows for an extremely close focusing distance, though I’m not taking advantage of it in this example. I target some flowers with lots of insect activity, in this case, a local ecotype of Monarda fistulosa, in the Lamiaceae, the Mint Family. Then I wait for insects to visit the flowers, within range of the camera.
I use the tripod handle to pivot up and down; it turns side-to-side easily. Ease of rapid movement with stability is critical, as the insect subjects move rapidly over each inflorescence, and from bloom to bloom. Still, the tripod only steadies my own shaky hands. The insects, of course, are moving, but so are the plants, which sway with the slightest breezes. A fast auto-focus helps; a quick hand is still needed when automation fails.
The mobility allows me to track a single insect as it moves around, and capture different shots, and perspectives, on the same individual. This is critical for identification, since I don’t know until later what the key features to look for might be. It’s often some tiny detail, only revealed from some obscure angle, that distinguishes the species.
My subjects, while largely oblivious to my actions, are not cooperative. I have to shoot hundreds of photos to get a few good shots that are in focus, free of motion blur, and have enough of the right details to identify the species, or at least narrow down to the family. This was never possible, or at least not economically feasible, before digital photography.
Macro shot of Pycnanthemum inflorescences, with common objects for scale: left, pencil eraser, right, U.S. nickle coin.
Eric Grissell, Bees, Wasps, and Ants: The Indispensable Role of Hymenoptera in Gardens
Douglas W. Tallamy, Bringing Nature Home: How You Can Sustain Wildlife with Native Plants
The Xerces Society, Attracting Native Pollinators:Protecting North America’s Bees and Butterflies
Links
The bug geeks at BugGuide are awesome. Only through their generous sharing of knowledge and expertise have I been able to identify my little visitors. They cover the United States and Canada.
Colletes thoracicus, Cellophane Bee, is a native species of solitary, ground-nesting bees. Solitary, because each nest is burrowed out by a single queen, who constructs several chambers in which to lay individual eggs. Solitary, yet communal: where they find the right conditions, the nests can be densely packed.Here’s a short video showing the activity on Saturday morning.
This is the third year for what I’ve come to think of as “my little bees.” I noticed the holes earlier last week, and saw all this activity last Saturday, as I was readying for the Plant Swap. This is the earliest in the year that I’ve noticed them.
Make Your Garden Bee-Friendly
These bees took up residence in a “neglected” spot of the garden, one of the benefits of being a lazy gardener/ecosystem engineer. Different species of bees have different requirements. Here are some things you can do to make your garden bee-friendly.
Avoid chemicals, especially pesticides.
Leave some areas of bare or muddy ground for ground-nesting species.
Set aside “wild” areas, even a few square feet.
Provide bee nesting houses.
Forego that perfect lawn, minimize lawn area, and/or mow less often.
Plant a diversity of flowering plants; bees prefer yellow, blue, and purple flowers.
Provide a succession of blooming plants throughout the growing season, especially early spring and late fall.
Provide a mix of flower shapes to accommodate different bee tongue lengths.
Emphasize native perennial plants. (See plant lists under Links below.)
Minimize the use of doubled flowers.
Select sunny locations, sheltered from the wind, for your flower plantings.
Originally published as a Guest Rant on Garden Rant on November 4, 2009. The original is no longer available on their Web site.
Colony Collapse Disorder (CCD) has been making the news rounds for a few years now. It’s old, if still current, news. Dire outcomes from the loss of honeybees have been proffered. For example, PBS recently introduced an online “ask the expert” feature with this:
Since the winter of 2006, millions of bees have vanished, leaving behind empty hives and a damaged ecosystem.
Really? The ECOSYSTEM?! Did they not notice that honeybees aren’t part of the ecosystem?
Honeybees are livestock. They are animals which we manage for our uses. We provide them with housing and maintenance. We even move them from field to field, just as we let cows into different pastures for grazing.
Perhaps, if CCD can neither be prevented nor cured, disaster would come to pass. However, the underlying cause would not be the loss of the honeybees but our dependence on them as a consequence of unsustainable agricultural practices.
The old ways of farming include hedgerows, uncultivated areas between fields. The biodiversity of these patches provide substantial habitat for native pollinators, as well as other beneficial insects. When even these rough “unproductive” patches of land are cleared, we set the stage for the patterns that have come to dominate agriculture: more herbicides, more pesticides, more machinery. All of these also damage the soil food webs that support both soil fertility and agricultural ecosystems. Although manufactured inputs provide temporary relief, they reduce the ecological functions of the land, requiring more and greater inputs to achieve the same effect. This is the definition of addiction, and it’s a clear sign that this way of doing business is unsustainable.
Why do we need to ship and truck pollinators around? There are plenty of native pollinators to do the job, where we haven’t decimated their habitats. There are 4,000 species of bees alone in North America. 226 species are known in New York City. Many of them visit my gardens in Flatbush, Brooklyn; some have even taken up residence. Many native bees are ground-dwellers which need only some open ground in which to dig their nests. When every patch of ground is cultivated, plowed under or paved over, native pollinators disappear. Suddenly, we “need” honeybees for pollination.
I care about the honeybees. I like my honey and beeswax candles. I support efforts to legalize beekeeping in New York City. But not at the expense of the biodiversity that is all around us, even in the city, if only we care enough to look for it, value it, and nurture it.
This beautiful creature is not a bee. It’s a fly of the Syrphidae, a family of flies renowned for bee mimics. This is Eristalis transversa, Transverse Flower Fly. I had noticed it in my garden for the first time this summer. yesterday was the first chance I had to capture some photos of it. Consider this a belated Garden Blogging Bloom Day post, but with a native pollinator as the focal point.
The flower it’s visiting is Aster novae-angliae ‘Chilly Winds’, a selection of the native New England Aster from Seneca Hills Perennials in upstate New York. This plant has been a pollinator magnet in my backyard native plant garden for weeks. It’s massive and overgrown and poorly placed, crowding out everything else around it. I’ll have to find it another place for next year.
Brooklyn: Monday, June 8th at Brooklyn Botanic Garden, 1000 Washington Avenue Staten Island: Tuesday, June 9th at Greenbelt Nature Center, 700 Rockland Avenue Bronx: Tuesday, June 9th at Van Cortlandt House Museum, Van Cortlandt Park Queens: Wednesday, June 10th at Alley Pond Environmental Center (APEC) 228-06 Northern Blvd. Manhattan: Tuesday, June 16th at Central Park, North Meadow Recreation Center (Off of 97th St. Transverse Road)
You can RSVP online, by emailing beewatchers@gmail.com, or by calling 718-370-9044.
I’ll take this opportunity to rant a bit. Honeybees, which we manage both for their products – honey and beeswax – and their service as pollinators, are a single, non-native, species of bee. Colony Collapse Disorder (CCD) has been widely reported for several years and is well-embedded in the public consciousness. Meanwhile, the circumstances of the thousands of bee species native to North America go unreported.
Much has been made of agriculture’s dependence on honeybees for pollination. Dire outcomes from the loss of honeybees – widespread crop failures, famine, even human extinction – have been proffered. Perhaps these things would come to pass. However, the underlying cause would not be the loss of honeybees but our dependence on them through unsustainable agricultural practices. Honeybees are livestock. They are animals which we manage for our uses. We provide them with housing, maintenance, even move them from field to field as we let cows into different pastures for grazing.
Native pollinators will do the job, but only if we leave them a place to live. We clear land for orchards and fields, removing the hedgerows and other “messy” places that had been their home. The monocultures of agriculture are magnified in the deserts of diversity they create. Of course we need to ship domesticated pollinators around (burning fossil fuels in the process); we’ve eliminated the native pollinators by destroying their habitats. In the process, we’ve also driven out native predators of plant pests, thereby initating the addictive cycle of pesticides, fertilizers, more and more inputs needed just to tread water on land until our systems collapse around us.
If that should come to pass, just don’t blame the bees.
One-third of our food depends on the services of a pollinator—bee or other insect, bird, or mammal. Bees are the most important pollinators in the Northeastern U.S., and there are more than 200 species of bees that live right here in New York City. We need to protect these local pollinators that help keep our parks and green spaces healthy and beautiful, and our farmers’ markets stocked with fresh produce.
In 2007, the Center for Biodiversity and Conservation and the Greenbelt Native Plant Center began the Great Pollinator Project (GPP) in collaboration with the Great Sunflower Project in San Francisco, CA. The goals of the GPP are: 1) identify which areas of New York City have good pollinator service (as determined by how quickly bees show up to pollinate flowers at various locations throughout the city); 2) increase understanding of bee distribution; 3) raise public awareness of native bees; and 4) improve park management and home gardening practices to benefit native bees.
If you are interested in our local pollinators, we need your help!
– The Great Pollinator Project
There are many ways to be a Bee Watcher:
Observe bee visitation at selected plants that will be distributed at our spring orientations. Conduct your observations in your own garden and submit your data online.
Become a Mobile Bee Watcher. Conduct your observations on flowers in your neighborhood or at selected bee gardens planted at various locations throughout New York City and submit your data online.
2022-05-29: This is now the FOURTH time WNYC has broken the link. Fixed again. (What the *^!% is wrong with them?!) 2022-04-13: Updated – yet again – the link to the recording which WNYC broke for the third time. 2012-05-21: Updated – again – the links which WNYC broke – again. 2011-08-23: Updated to current links from the old ones which WNYC voided.
Domestic Bliss: Blog Widow (left) and me in the gardener’s nook on the occasion of the interview. I had just transplanted the female Ilex verticillata in the background that morning. Two weekends ago, Blog Widow and I were interviewed by WNYC’s Kathleen Horan on the topic of marriage equality – marriage for all – in New York state. The piece aired this morning, and is available on the WNYC News Blog. We make our appearance about 4:55 into the segment.
I didn’t get to listen to it when it aired at 7:50am this morning. I thought it might be off-topic for the blog. But since most of my part of the aired conversation is about the garden, I figure it it’s not much of a stretch. Please give it a listen, and let me know what you think in the comments below.
I’m no entomologist, but I think this is the same species, Colletes thoracicus (Colletidae), Cellophane Bees, that “bee guy” John Ascher identified from my photos last year. This is an individual from a colony that appeared this week in the same place it appeared last year about this time.
We’ve had rain almost every day for a week. Yesterday I had the day off, and the weather also took a break, with sunny skies and temperatures in the 70s (F). Seems like perfect digging-in-the-ground conditions to me.
The area of activity is much larger this year than last. I wish I had a video camera. In the area of this photo, there were at least 30-40 bees flying around, but I can’t pick them out from the photo at this scale and resolution.