Journal archives for July 2017

July 01, 2017

Biosurveillance: Wasp Watching 101

Wasp Watchers is a citizen scientist biosurveillance program hosted by the University of Minnesota. The objective is to monitor the nesting sites of the buprestid-hunting wasp, Cerceris fumipennis, for the invasive Emerald Ash Borer. Yesterday I received from the director of the program a list of ball fields in and around Northfield to survey. One of the sites is just a few blocks from our house, so today, late in the morning, Lisa and I walked the dog in that direction.

The playing field at Greenvale Elementary was quite weedy and unmown. I walked the perimeter looking for nests and found none. Turning my attention to the rest of the field I noticed several black wasps flying near the center of the field, Cerceris fumipennis.

I returned to the field in the afternoon with my net and camera and spent an hour, from 2pm to 3pm, watching the wasps. During this time I found two nests. There were probably more nests because they were very difficult to locate among the weeds growing on the field. The two nests that I found did not have any beetles abandoned near the entrance. And I wasn't able to collect any beetles from wasps returning to their nests (I didn't see any return to their nests with prey either).

Posted on July 01, 2017 03:18 by scottking scottking | 8 observations | 0 comments | Leave a comment

July 02, 2017

Queen Ant Kidnapper

Mid afternoon. Cowling Arboretum. Mostly cloudy at the beginning of the hike as I set out to look for Queen Ant Kidnapper wasps.

Because it was the weekend, quite a number of people fished the banks of the Cannon River. At one location an extended Hmong family fished—moms and dads, grandmothers and grandfathers, infants in car seat carriers, music, and coolers of food—obviously there for the duration. I said hello to several of the family members and kept walking, headed to the sunny upland trails to search for wasps.

On the gravel trail along the edge of the prairie, I saw no clubtail dragonflies (I've seen them here in the past) nor any wasps. The weather was warm enough but to overcast. On the sandy access road, where I'd discovered the Queen Ant Kidnapper last summer, numerous wasp nests were present, many looked freshly dug. A single wasp flew down the road ahead of me, disappeared, and did not return.

I crossed Highway 19 and visited the Carleton College baseball fields, thinking I might find another Cerceris fumipennis nesting site there. The fields, which I'd never visited before, were immaculately cared for, but they were also empty, fenced, and padlocked. The low strata of clouds drifted away and the sun came out. I turned around and revisited the wasp sites.

On the sandy access road, several wasps were now active, flying, digging, or simply peeking out of their nests. A Weevil Wasp (Cerceris clypeata) peered cautiously from one mound-shaped nest, recognizable by its solid yellow facial markings. Several feet away, out of a tunnel-shaped nest, the digging cast out in front of the entrance, a Queen Ant Kidnapper made an appearance, the yellow markings of its face divided by two wide vertical stripes. This was the wasp I'd hoped to see. In the days and weeks ahead, this wasp will hunt and provision its nest with queen ants.

Pleased to have found the wasp I went searching for, I headed toward the car. However, I was soon delayed by more wasps. On the gravel trail along the edge of the prairie, several black wasps were flying. These turned out to be Cerceris fumipennis. I'd passed by these nests earlier; with their large entrance plugged with sand from within (when it was cloudy) I mistook them for anthills. I counted five active nests (there were probably more). I watched one wasp carrying a beetle drop directly, without landing, into its nest entrance and disappear. Another returning wasp appeared, flying slowly. I didn't have my net, but I'd read, just this morning, that you could tap the wasp with your hand while it was flying and it would drop the beetle it was carrying. I gave it a try. I followed the wasp and tapped it. It landed on the ground and then flew away. Where it had landed, I found a slim, metallic beetle. It worked!

Posted on July 02, 2017 03:08 by scottking scottking | 6 observations | 0 comments | Leave a comment

July 03, 2017

Thirteen Nests

Late in the day. English Plantain in bloom several places along the trails. I saw a single White-faced Meadowhawk perched on the tip of a dead branch at eye level. How long before these first meadowhawks take on their mature red color?

After the previous day's successful biosurveillance, intercepting the hunting wasp and capturing its prey, I keenly anticipated more, but I wasn't able to make it into the field until late in the day, well after the peak hours of wasp activity, so I settled on some simple reconnaissance work. There had been zero Cerceris nests on the practice field when visited several days ago. Today, I numbered thirteen nests (literally scratching the number into the infield dirt adjacent the nests) and there were wasps flying.

As I surveyed the ball field, a small mystery presented itself—not all nests were the same. In fact, there seemed to be four distinct varieties (if indeed they all belonged to Cerceris fumipennis): 1) active nests that had a large mound of sand with a large opening in the middle; 2) closed nests that had a large mound of dirt with the opening plugged by the wasp with sand from within; 3) exit holes of the same diameter as the active nests but without and mounded sand around them; 4) small pushed up mounds of sand. I suspect the latter may be wasps preparing to emerge? One of the flying wasps, a female, landed and inspected one of these small mounds. It then flew and landed at a second one of these small mounds before flying off for good.

George and Elizabeth Peckham, who studied a variety of wasps near Milwaukee, Wisconsin, over a century ago, had this to say about our wasp: "Fumipennis, large and handsome, with a broad yellow band at the front of the abdomen, is another wasp that has no regard for the convenience of the people who are watching her. You may sit by her big open hole for hours without seeing her, and when she comes she drops in so suddenly that, unless you are very much on your guard, you are not sure even then what she is." (from Wasps: Social and Solitary, 1905)

Posted on July 03, 2017 02:52 by scottking scottking | 3 observations | 0 comments | Leave a comment

July 04, 2017

An Hour In The Sun

"To a student of insects high summer is no time for dreaming: it is a time for being afoot and alert. The world of insects is at its shrill crescendo, in a few short weeks to fade to a whisper and then to months of silence." -- Howard Ensign Evans, from Wasp Farm

Now that several populations of Cerceris fumipennis had been located, the wasp work began.

One hour of wasp watching at Greenvale Park from 11:30 to 12:30. Wasps flew continually over the scruff of vegetation covering the ball field. Perhaps some of these flights were orientation flights? Many, however, seemed more searching, perhaps searching for locations to found a new nest? And there were more nests than before. During the hour, I netted just one wasp that was carrying a beetle. As I was leaving, I interrupted a Great Golden Digger Wasp excavating a nest at the edge of the ball diamond. I crouched in the grass near where it circled. My presence bothered it, but eventually the wasp returned to her nest and began digging again. Intermittently she'd stop digging and fly up and inspect once more this new large object present in her space, hovering very near my face and sometimes around the camera I was holding. The bright orange abdomen and legs, the golden hairs on face and thorax, and the inquisitive, knowing vigilance are certainly a few of good reasons to admire this wasp.

A second hour of wasp watching from 1:30 to 2:30 at St Olaf yielded similar results: a single beetle. Most entertaining at this site were several sand wasps, probably Bicyrtes, that raced across the bare surface of the practice field so close to the ground and at such speed that they resembled race cars cruising the salt flats of the Great Basin.

Posted on July 04, 2017 03:16 by scottking scottking | 5 observations | 0 comments | Leave a comment

July 05, 2017

Buprestid Bonanza

I visited the Cerceris fumipennis nesting site at the Cowling Arboretum from noon to 1pm. Clear, sunny, hot and humid---ideal wasp watching conditions (ideal for the wasps not the watcher!). I counted twenty two nests. I found three abandoned beetles, beetles dropped and left outside the nests by the wasps. In addition to the abandoned beetles, I was able to collect four beetles by gently tapping the returning wasps with my hand. Seven beetles total, a Buprestid bonanza compared to the single beetle collected during my previous visit.

Two of the beetles, one abandoned (Buprestis sp.) and one captured (Dicerca sp.), were very large. If I hadn't seen the wasp flying with the one beetle, I wouldn't have believed it possible. This feat raises further question of how the wasps capture these giant, well-armored beetles to begin with.

A lot of other wasp and bee activity occurred all around me, which I had to neglect while keeping my vigil for returning Cerceris wasps. I did manage to photograph an incoming Ant Queen Kidnapping Wasp, though I wasn't quick enough to get a photo of the kidnapped ant queen that the wasp left momentarily at the entrance of her nest. By the time I looked at it and recognized what I was seeing, the wasp grabbed it and whisked it into her burrow, a large reddish ant with wings, maybe Lassius sp.?

Posted on July 05, 2017 04:26 by scottking scottking | 8 observations | 0 comments | Leave a comment

July 06, 2017

Sizzled Synapses

Another very hot and very humid day. Fortunately, throughout the morning hours, thin clouds shielded us from the blazing spearpoints of the sun. Even still, without direct sunlight, the temperature reached the upper 80s by late morning when I visited the Cerceris fumipennis nesting site at St Olaf. For a half hour, I paced about the gravel of the practice field, ready for the wasps to take flight and return with their captured beetles. Instead, they seemed content to wait for more favorable conditions, simply hanging out at the entrance to their nests, peering placidly at the bright, yet overcast sky. Several diminutive males made the rounds. Not much else happened. I could see blue sky at the horizon to the northwest (perhaps the wasps could as well?), so I decided to leave and return later if the clouds passed.

By 1:30 the sun was out, the sky solidly blue, the afternoon sweltering. Surely the wasps would be active now. I grabbed my net and several vials for beetles and resumed my vigil at the practice field. There was even less activity than before! The wasps had departed from the nest entrances and, at first, I took this to be a good sign, that they were off procuring beetles. But as the minutes ticked by no wasps returned. Heat mirages distorted the landscape. Sweat stung my eyes. My purpose, my patience thinned and melted away; a molten disenchantment pooled in its place. The connection between earth and sun glittered and sparked like sizzled synapses. I left the ball field beaten, shut out.

Posted on July 06, 2017 03:13 by scottking scottking | 6 observations | 0 comments | Leave a comment

July 07, 2017

Natural Causes

A dead Four-spotted Skimmer was found on our driveway this afternoon. Mysteriously, the dragonfly held a rather life-like pose. It looked as though it had died while perched, dried in that position, and then fell to the ground, dislodged perhaps by a gust of wind. This brought to mind an old question: How often do dragonflies die of old age? I've wondered about this off and on. Many adult dragonflies, at least in the northern latitudes, live long enough to succumb to the frosts and freezes of autumn and avoid predation that way. Still, a death by natural causes and not a death caused by nature (i.e. bats, birds, frogs, fish and other dragonflies) seems to be a rarity. In fact I know of only one eye-witness account. Ken Tennessen, fellow odonatologist and poet, once told me of a time he was watching a dragonfly and it just quietly fell from its perch, dead. "It has to happen on occasion," he added, after a quiet philosophical pause.

Posted on July 07, 2017 12:22 by scottking scottking | 7 observations | 5 comments | Leave a comment

July 08, 2017

Gold-marked Wasp

Posted on July 08, 2017 03:34 by scottking scottking | 10 observations | 0 comments | Leave a comment

July 09, 2017

Western Red Damsel

Posted on July 09, 2017 02:59 by scottking scottking | 1 observations | 0 comments | Leave a comment

July 10, 2017

Green-eyed Wasp

Posted on July 10, 2017 03:50 by scottking scottking | 1 observations | 0 comments | Leave a comment