Monday, August 31, 2009

Grape is Blooming

Wild grape is blooming along the edge of the Campus Pond here at the University of Massachusetts in Amherst. That is cause for excitement for me because the blossoms are a magnet for a variety of wasps and bees. While occupied with nectar-sipping, they are fairly easily approached, though they are still constantly on the move and wary of my camera.

I have seen at least three species of yellowjackets alone, including the “aerial yellowjacket,” Dolichovespula arenaria, also known as the “Sandhills hornet.” They build their paper nests aboveground, often under the eaves of houses.

Another species of yellowjacket commonly seen right now is Vespula vidua. They nest underground, in abandoned rodent burrows and other natural cavities. Like the aerial yellowjacket, they are strictly predatory on other insects, especially flies, which they chew up and feed to the larvae back in the nest. They do not scavenge at picnics and barbecues like more abundant urban yellowjackets.

Paper wasps are also social insects like the yellowjackets, but their colonies are much smaller in number of individual wasps, and the nests are uncovered paper combs. Here, the most abundant species is the introduced “European paper wasp,” Polistes dominula. They have been immensely successful at exploiting their new homeland, maybe due to their aggressiveness. This worker repelled all other wasps from its perch on these blossoms. Why it was guarding that particular bundle of flowers is beyond my understanding of the species.

Solitary wasps also flock to grape flowers. This grass-carrier wasp, Isodontia mexicana, is a case in point. They are fairly easy wasps to recognize because they usually alight with their wings splayed out away from their bodies, exposing the thin “wasp waist,” a petiole that links the abdomen to the thorax.

Much larger than the grass-carrier, but in the same family (Sphecidae) is the “great black wasp,” Sphex pensylvanicus. They tend to flatten their wings over their backs while probing the blossoms with their tongue-like mouthparts. The brilliant blue reflections of the membranes make them a truly spectacular insect to observe.

Perhaps the most regal of all the wasps at the grapevines is the aptly-named “great golden digger,” Sphex ichneumoneus. Females of this species, like those of the great black wasp, dig burrows in the soil, storing paralyzed katydids inside as food for the single larval offspring that develops in the subterranean nest.

I enthusiastically recommend wasp-watching to anyone with even a passing interest in insects. They are placid animals when foraging for the carbohydrate-rich nectar that fuels their flight. You can literally get nose-to-nose with them without arousing their aggressive streak. See how many species you can observe, and share what you find with others.

Saturday, August 15, 2009


I just changed my residence here in South Deerfield, moving to the house next door (literally). Unfortunately, it does not have wireless internet, so it may be awhile before I am able to blog again. I am writing this from a cafe' right now, just before closing. Stay tuned, though, more to come.

Sunday, August 9, 2009

Panning for Bees

Yesterday (Saturday, August 8) I was invited to participate in a mini survey of local bees on the grounds of the Mount Grace Land Conservation Trust in Athol, Massachusetts. It was a unique event that revolved around the use of “pan traps” for bees and other insects that had been set out the day before.

We were fortunate to be under the guidance of Joan Milam, a largely self-taught bee expert from nearby Montague. She explained how pan traps are normally deployed. Pans (disposable plastic bowls were used in this case) of different colors are filled with water to which a single drop of detergent is added to break the surface tension. Bowls that are white, yellow, or blue seem to be most attractive to the wide variety of bees found here. They are often arranged in arrays, the distance between bowls carefully measured. Each separate trap can be addressed as its own sample, or the entire array can be the collective sample.

We collected the bowls, pouring the contents into a mason jar and then filtering the water and soap out with a piece of windowscreen fitted under the screw-on rim. Back inside the offices of the land trust we set about the task of rinsing and drying the catch. Turns out that bees and many other insects can take a surprising amount of abuse in the rinse and “tumble dry” cycles without undo damage. The biggest challenge is not melting the chitin in the exoskeleton.

Meanwhile, a few of us took our time in the field looking at what was currently on the goldenrod and other flowers, that might have escaped the pan traps. One such pollinator was this female leafcutter bee in the genus Megachile. Another was this flower longhorn beetle, Judolia cordifera, brought back to the makeshift lab where I took its picture before releasing it.

Several folks brought microscopes and we set about sorting the bees from look-alike wasps, flies, and other insects, then pinning them and further identifying them to family, genus, and species where possible.

This “crash course” in bee morphology was well worth it. We even got lunch provided, and took home a handy hand-out for our own use later. Special thanks to Sarah Mildren, Learning Services Coordinator, and Sean Pollock, Director of Finance and Operations, both of the Mount Grace Land Conservation Trust, who facilitated and hosted the event, and to Joan who was so patient with us novice bee people.

Sunday, August 2, 2009

More Beetle Excitement

I got some exciting news this past week that I thought I would share. It involves a species of beetle that I collected while on a photo outing on the Fourth of July near the Quabbin Reservoir in Franklin County, Massachusetts.

While in a forest clearing (well, more of a slash pile of logging residue, actually), I saw a metallic woodboring beetle in the family Buprestidae. It seemed non-descript, much less brilliant in color than others I have seen, but I took its picture anyway. I wanted more images, though, so I captured it alive in a vial and took it home.

After chilling this highly active animal in the refrigerator, I placed it on the kitchen table and took more images. I was finally able to see that it was more or less metallic purple, the granular violet nature of its exoskeleton reflecting the light from my camera flash. It looked like the beetle had perhaps hatched out of a geode rather than a pine tree.

I posted my two images, one “in the wild” and the other “staged,” to in the hopes of confirming my identification of it as Buprestis striata. Much to my surprise, the consensus among the experts is that this is actually a specimen of Buprestis sulcicollis, a much less commonly-encountered species. It was, in fact, previously unrecorded for the state of Massachusetts, though long suspected of occurring here.

Getting a state record is reasonably remarkable, but considering that I have been here in Massachusetts for a grand total of two months, it feels pretty spectacular. It would be great if it translated to a wage increase, but alas, I suspect all I will get out of it is “this stupid t-shirt” equivalent. As luck (good or bad depending on your viewpoint) would have it, the beetle subsequently died before I got around to releasing it. I will get to decide where the specimen will be deposited, which is a reward unto itself, I think.

The beetle deserves a bit of notoriety, too, but very little is known about Buprestis sulcicollis. Adult beetles measure from eleven to 15.5 mm. The recorded hosts for the larvae are pitch pine and eastern white pine. Its distribution is mostly from the Great Lakes to the Atlantic seaboard, but there are records as far west as Alberta and the Northwest Territories.

I encourage each of you to not assume that whatever creature you encounter is common, known from your area, or even already known to science. Take pictures, note the habitat, any behaviors you observe, and record the date and precise location you found the organism in. You never know what may become of your patient and careful study.