Apidae – Carpenter bees, Squash bees, Blueberry bees, Cuckoo bees

Carpenter bees

The carpenter bee, xylocopa virginica, is typically large and black. Similar in appearance to the bumble bee, it is distinguishable by a nearly hairless upper abdomen, which makes this area appear glossy. It is frequently found in and around metro Atlanta and often causes quite a stir in urban areas because of its nesting habit.

Flickr user: Ian Marsman

Photo credit to Flickr user: Ian Marsman

Female carpenter bees excavate wide tunnel systems in wood where they build there nests, often to the chagrin of homeowners. As well as being considered a bit of a rogue because of their penchant to bore into window trim, they are also known for their non-conventional foraging. Occasionally, when visiting long tubular flowers, female carpenter bees will “rob” the nectar by slitting the flower at the base, taking the nectar and circumventing the pollen-covered anthers and the stigmas.

Carpenter bees in your garden

Carpenter bees can be found in high numbers in Metro Atlanta gardens. In early spring, male bees will often “patrol” promising mating sites, chasing away any other males, and in the process, cause some alarm to the human gardeners sharing their environment.  Although they may appear to be viciously dive-bombing your guests as you take them on a stroll of your new greenspace, they cannot sting.

Don’t be perturbed by their bad rap. Carpenter bees are an important native pollinator. You can have a lovely intact wooden porch and also harbor a nice garden with carpenter bee pollinators present. Building carpenter bee boxes will allow for a nesting site that is amenable to bee and human.  The best part about installing one of these beauties is that carpenter bees  will often return to the exact same nest year after year. So once the bees have established a nest inside your man-made nesting box, they will stay in the bee box and not in your house!

Another tip: ensure that any of your exposed wood on the house is painted, this will ensure no holes. Carpenter bees will only nest in unfinished wood.

Squash bees

Squash bees are native bees from two genera (Peponapis and Xenoglossia) who pollinate the flowers of squash, pumpkins, and cucurbits. They are extremely efficient in pollinating these species because their “work schedules” are finely tuned to the daily rhythms of the cucurbit flower.  They arrive to forage early, when the flower opens, to gather nectar and pollen quickly and then depart the flower just as fast.

Photo Credit: James H Cane. USDA-ARS Pollinating Insect Research Unit. Utah State University, Logan, UT

Photo Credit: James H Cane. USDA-ARS Pollinating Insect Research Unit. Utah State University, Logan, UT

As an underground nester, these bees will often reside under the very plants in which they are responsible for pollinating. They prefer to tunnel in high, well-drained bare soil, and can also be found under rocks or other objects. The key to keeping happy squash bees is to not disturb nesting sites, as they will return each year and form large nest aggregations. Most cucurbit growers are well aware of these underground wonders and try and participate in any type of conservation efforts to ensure that their numbers do not decline.

Squash bees in your garden

These species are only likely to be in your pollinator garden or greenspace if  you have included members of the cucurbit family. Peponapis pruinosa (squash bee) is found in Georgia, its prevalence in an urban setting is limited to larger parcels of land with some form of agriculture. They are mostly found in the mountains, out toward the coast, or in flatwoods with shallow water tables.

GAPP’s goal to incorporate green space within a 25-mile radius around Metro Atlanta would lend itself to the possibility of including farmlets and coop farm groups located on the border or outer rim of the interest area. Areas like this should definitely support programs that focus conservation efforts to attract this type of pollinator .This would also be a great species to encourage visitation in community food gardens.

Distribution for Peponapis pruinosa has also been shown to correlate heavily with regions that have a high level of cucurbit agriculture. Furthermore, the distribution of squash bees has shown to adapt to new regions when cucurbit agriculture has expanded into new growing areas. Therefore, increasing the awareness of these native pollinators may help to increase the number of pollinator-based gardens in the urban and outer Metro Atlanta areas that include agricultural species.  In particular, community gardens and food cooperative farms, that are already food species based. Raising awareness also helps to discuss ethical management issues for native squash bees and their presence in the agricultural industry.

Southeastern blueberry bees

The majority of large-scale blueberry agriculture in Georgia will lie outside the GAPP garden radius, and therefore dictates a natural correlation that there will be minimal numbers of Habropoda laboriosa found in urban pollinator gardens.

Phot credit: Wikipedia, Author: Jerry A. Payne

Phot credit: Wikipedia, Author: Jerry A. Payne

However, it is important for GAPP members to understand  these important species.  Female bees of the species use sonication or “buzz pollination” when visiting flowers. They attach themselves lightly to the flower and vibrate their flight muscles to shake or dislodge the pollen from the anther onto the bee. The next flower that is visited gets the same treatment, except this time the old pollen gets shaken off onto the stigma and new pollen is deposited back onto the bee and so forth and so on.

By using buzz pollination, Habropoda laboriosa leads to a handling rate 3 times faster than a comparative Bombus species. Also, Southeastern blueberry bees are only active for a few weeks every year. Want to take a guess what week that is? The exact same week that blueberries are in flower. Talk about specific pollinator and flower interactions! This pollinator relationship was built to last.

Cuckoo Bees

The group Nomdinae within the Apidae family is made up of exclusively parasitic bees. At last count over 795 species have been identified worldwide. Nomada bees are usually red or yellow with whitish markings, often resembling wasps, and have smokey wings or wing tips. See the picture of Nomada succincta below

Nomada succincta

Photo Credit to Wikipedia user Darkone

Aptly named cuckoo bees because of their parasitic egg laying behavior, the female will lay her eggs in the nest of another bee reminiscent of the behavior of a cuckoo bird.  In general, when the cuckoo bee larvae hatch, they consume the host larvae’s pollen ball and then, if it was not already undertaken by the egg-laying “mother”, the larvae will then eat the host larvae as well. In other cases, if the host species is social, the cuckoo bee will remain in the host’s nest, laying eggs and sometimes even killing the queen and adopting the role for herself.

Because of this parasite behavior, cuckoo bees have lost the adaptation to carry pollen as it is not a function that they must carryout. Rather, the pollen is taken from the host’s nest.  They are nearly hairless (no need for fluffy hair Bombus style) and are generally wasp-like in appearance.

Nomada in your pollinator garden

Records for the range for this type of bee are scarce in Georgia. Some records indicate that specimens have been found in Savannah and Athens and populate the state from February through May. However, it is well known that many cuckoo bees parasitize the nests of bees in the family Andrenidae, and species from this family are recorded as present in Georgia.

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