My garden has been buzzing with activity for the last two (sunny) days: squirrels, bunnies, birds, and bugs big and small, are all over: scavenging, digging, hunting or simply, eating. As long as they do not overwhelm my crops, I do not lament sharing, even with the pests to some extent, for without them, I might not have the beneficial insects coming to hunt, in this reunion of local Fauna. In past years, I have featured some of these garden heroes, such as ladybugs and fireflies, as well as wasps, and pollinators such as bees and butterflies; even the not so innocent ants got a mention, but … flies? Other than the house, fruit, horse and black flies (all terrible!), and the equally cussed mosquitos, there are thousands of other species of flies, bad or beneficial, and in fact, their taxonomic order, Diptera, is considered to have around one million species! The Syrphidae Family, commonly known as hover flies, or flower flies, are great pollinators, in spite of their small size 8-12 mm in length; many species in this family have evolved to mimic bees or wasps as protection from predators, since they do not have stingers.
Some differences that help identify bees, wasps and hover flies are: 1) Antennae – flies have very short and thick ones, wasps’ are long and straight, and bees have long, often bent (elbowed) antennae. 2) Wings – bees and wasps have two pairs, while flies have one pair (Diptera comes from the Greek words di – two, and pteron – wing). 3) Body shape – wasps have a narrow waist, while bees are more round, and flies are even chunkier. 4) Legs – Wasps have long legs, and bees are often hairy or have pollen sacs in the hind legs. 5) Eyes – bees and wasps have solid eyes, often dark, while flies have segmented-multiple eye structure, with the characteristic “ski goggle” shape.
Armed with this information, what kind of insect do you think is the one featured at the top of this post, feeding from a calendula flower? (See my answer at the end of the post).
I have tried to identify a few other flying insects in my garden from photos I took yesterday:
In the photo below, left, it was hard to see all the features in the little guy coming from inside a red rose. It looked chunky, so I guessed it was not a wasp; its tiny size and hardly visible antennae were inveigling towards granting a fly ID, but its true nature became clear after looking at a close-up once it was out of the flower (photo below, right):
Notice the long, curved antennae, now in full sight, and more importantly, the pollen sacs on the hind legs so, it was definitely a bee! I learned that bees from the family Halctidae are amongst the smallest species, with 5 to 10 mm in length, and get the common nickname of “sweat bees” from the habit of landing on people to collect the salt from their skin during hot summer weather. They have the capability to sting, but are generally calm, and are great pollinators.
The next subject was much larger, seen in the photos below flying around some asparagus fronds. On the left, the side view shows a slender bug with long hind legs, pointing to a wasp. The photo on the right, showing a view from the top, confirms that it was a wasp from the very narrow waist:
The characteristic stripe pattern on the body, and orange antenna tips further identify it as a European paper wasp (Polistes dominula), now common in the US and Canada, and considered invasive. In the garden, these wasps are still beneficial, though, since they hunt other insects and their larvae, to feed their young, and might occasionally spread pollen as they chase their victims.
The last photo, below, shows two clear representatives of the hover fly family collecting nectar from a male watermelon flower; their stripes are mimicking bees, but they have a single pair of wings, and “ski goggle” eyes:
As the good pollinators that they are, I am sure they have also visited some female watermelon flowers (with the bulgy bottom), like the one shown below, left, since my vines are already growing some fruit (photo below, right):
So, I ended up identifying examples of three types of beneficial insects in my garden: sweat bee, European paper wasp, and hover fly. How about the one at the top of this post? It is a small specimen and the wings are folded so it is hard to see if they are single or double, but in the close-up below, it is possible to appreciate the solid black eyes and bent antennae … it’s a bee!
FUN FACT: The city of Toronto, in Ontario, Canada, has chosen the Bicoloured Agapostemon (Agapostemon virescens), a metallic green sweat bee, as “Toronto’s Official Bee”. In the city’s website, it is explained as “… an ideal choice as Toronto’s Official Bee for several reasons:
- It is easy to identify. No other insect in our area has a brilliant bright green head and thorax combined with a black abdomen. The males are also bright green at the front but their abdomen is yellow and black striped.
- It is a common bee. The females can easily be found in early summer mornings foraging on thistles and other flowers. The males can be observed flying slowly around flowers looking for females.
- It is welcoming. Females form communal nests in the ground. Their social set up is similar to a condominium with one entrance that is shared by all occupants, but each has its own separate unit. Up to two dozen females may share a single nest entrance, but each individual builds its own burrow. One bee usually guards the entrance, with only her head visible from above ground. There is strength in numbers, which is why these bees allow other Bicoloured Agapostemon individuals (complete strangers) into their nests to increase entrance surveillance. Most bees will defend their nests against others of their own species, but our official bee is much more tolerant of newcomers, and this makes it a particularly appropriate choice for Toronto’s Official Bee.“
FUN FACT: There are close to 2,000 species of bees native to Mexico, but beekeeping for honey production includes both European Honey Bees (Apis mellifera) and native species. Honey from different species differs in its flavour, and also in productivity, since colony sizes tend to be much bigger for European bees, compared to native Mexican bees. Honey was consumed in pre-Hispanic Mexico, called neuctli in Nahuatl language, and in spite of the introduction of the more productive European honey bee, native apiculture has remain alive in the country; many Mexican beekeepers still cultivate and harvest honey using pre-Hispanic techniques, such as the use of clay pots, and they find native species easier to handle because many of them do not sting.