Showing posts with label observing. Show all posts
Showing posts with label observing. Show all posts

Sunday, October 6, 2019

Shoot First, Ask Questions Later

Shoot it with a camera or your phone, though. Yesterday I once again found myself grateful for having paid attention to something I could have easily dismissed. Nothing bad can ever come from taking a moment to take a second look, and recording that observation whenever possible.

© Gary Larson via Pinterest

As a volunteer expert on social media, I cannot count the times someone has begun their post in an insect identification group with "I don't have an image, but...." I am tempted to start replying "Well, I don't have an answer, but...." I would never do that. I enjoy a good mystery too much, and believe in rewarding curiosity and a desire to learn.

There is still no substitute for a clear image of the creature you would like identified, and increasingly there is no excuse. Smart phones can now take professional-grade images that only dedicated cameras could manage a few minutes ago. You are forgiven if you had other priorities at the time, like eating, being engaged in an important conversation, or in a business meeting, for example.

The situation I am referring to is when you are out observing wild things anyway, and you still decide not to bother recording something. This is a failure I am occasionally guilty of, too, but I am working to rectify it. It gets worse the more you think you know, the more you think you recognize a specimen without close inspection.

A male Variegated Meadowhawk dragonfly

Yesterday I visited the Pueblo Reservoir Wildlife Area west and north of Lake Pueblo State Park in Colorado, thanks to my friend Tim Leppek who has been there many times and knows the area well. As is our custom, we made scant horizontal progress over several hours of walking along the mostly dry basin and channel. Dragonflies were still in abundance, mostly meadowhawks in the genus Sympetrum, as they persist late into autumn.

A male Striped Meadowhawk dragonfly

One dragonfly stood out, its wings shimmering more brightly than the others. I almost dismissed it as a teneral specimen, one that had just recently emerged as an adult, with mature adult pigments yet to manifest themselves. It flew relatively weakly as well, which is also typical of newly-minted adult odonates. I took a picture anyway, in the harsh afternoon sun, then reviewed the image on my camera screen and reacted "what the..??" I looked up from my camera and the crystal phantom was nowhere to be seen.

Fast forward to after I returned home, and began looking in my dragonfly books. There were no obvious photo matches in any of them. The closest approach was a female Bleached Skimmer, Libellula composita, the name alone being most appropriate considering how bright the thing was in the field. Looking online I finally managed to find a couple of images of that species, and that gender, that did match.

The female Bleached Skimmer

The Bleached Skimmer is well known from southeast Colorado, with records from Weld, Kiowa, Prowers, Bent, and Pueblo counties. The first specimen dates to July 11, 1991 in Lincoln County. The one from yesterday may represent the latest date for the species in Colorado, but I'll have to check with all the relevant authorities to know for sure.

Think about what you might be overlooking, and look again. Devote a few pixels to it. Share it. Maybe it is something common and well known in your area. There is no shame in redundancy if that is the case. Eventually, something you spot won't be common or well known, at least in your location, and your observation will be greeted with great appreciation by the scientific community.

Saturday, July 28, 2018

Wasp-watching

It has been difficult to build-up enthusiasm this summer because insect abundance is way down here in Colorado Springs, but when I get to witness an event like I did yesterday, it makes me glad I went out and made an effort.

Female Ammophila sp. with heavy load

I happened to glimpse a very odd, fairly large insect out of the corner of my eye. It took me a minute to realize it was not a single insect, but two: a female Ammophila sp. thread-waisted wasp toting a caterpillar she had paralyzed. She was trying to locate the concealed nest burrow she had excavated before going hunting, and was wandering around rather aimlessly, but at high speed.

At one point she cached the caterpillar so she could orient herself without such a burden. It worked. She found her burrow, then went back and got the caterpillar. I was lucky to get any images of the transport because she moved so speedily and kept going in and out of focus. Even an attempt at video may have been almost useless. Her agility, with such a heavy load, was impressive. It would be like you or me running at full speed carrying a sofa between our legs.

Removing the "door" to her burrow

She abruptly dropped the caterpillar, and in a matter of seconds uncorked the stone plugging her nest burrow. She quickly entered her burrow, turned around inside, and re-emerged to grab the caterpillar and pull it in. She has to be this fast to avoid tiny parasites known as "satellite flies" that will lay tiny maggots on the caterpillar before the wasp can get it secured underground. Indeed, there was at least one miltogrammine fly flitting at the entrance to the burrow.

Pulling the caterpillar into her burrow

About a minute or so passed with both the wasp and her caterpillar underground. Finally, she emerged topside and quickly retrieved the stone that had plugged the burrow opening previously. She replaced the stone and began kicking sand on top of it. Notice how she curls her front "feet" to maximize the tarsal rake of spines that aid her in digging and filling. At one point she was startled by a curious ant and took to the air for a spit second. Ants can raid wasp burrows and cart off the caterpillar and wasp egg as food for their own young back at the colony.

Replacing the "door" to her burrow

By now I was getting a bit stiff from having stood in the same place for a long while. When I left the wasp, she was apparently unsatisfied with the nest closure and was actively chewing down to the rock plug. I left her in peace to finish what she had started.

Kicking sand to conceal the entrance

The whole sequence of events involved in the provisioning of a nest by a solitary wasp is truly remarkable. She has to dig her burrow and, load after load, flies off with armfuls of soil to fling across the landscape, lest some predator or parasite recognize her nest from piles of "tumulous" around the opening. Next, she fills in the burrow entrance, obliterating all evidence of any cavity whatsoever. She may make a brief orientation flight and then go off to hunt. How does she ever find the burrow again? We cannot even remember where we parked our car, or left our cell phone, and we reportedly have much larger brains than wasps do.

Startled by an ant

Once she has completed her mission of providing one paralyzed caterpillar for a single offspring, she goes off to start the process all over again, somewhere else. Does the wasp immediately forget about the burrow she just completed? How does that instinct work? It has to be plastic enough to address unique situations and overcome obstacles.

Up and away for good?

Over the coming months, in that underground cell, a wasp larva will hatch from the egg and begin consuming its still-living but inactive larder. Scientists believe that insects have no pain receptors, so that must be a blessing to the caterpillar. Were it deceased, though, the caterpillar would quickly rot under the assault of bacteria and fungi. After consuming the caterpillar, the wasp larva enters the pupa stage, as equally inert as the caterpillar on the outside, but inside the pupa there is a massive reorganization of cells converting the grub-like larva in to a sleek, winged adult wasp. Some genes are turned on, others are turned off. It is amazing to contemplate that a wasp larva, or caterpillar, has inside it the latent ability to execute all the behaviors of the adult. It somehow "knows" it cannot fly, does not need flower nectar, and cannot reproduce as a larva. It understands at some fundamental level that its only job is to eat and grow.

Some finishing touches

The next time you are out hiking, and a wasp flies up from under your feet, stop for a second. Back up a little. Does the wasp return to the vicinity? If so, keep watching. She is probably in the process of working on a nest burrow and will resume her activities if you stand still. It takes a little practice just to think about this possibility, but the rewards can be astonishing.