Readers’ wildlife photos

August 23, 2015 • 7:50 am

Let’s begin with photos from our most regular regular, Stephen Barnard of Idaho. He sent three pictures of the Eastern Kingbird (Tyrannus tyrannus) with the note, “You don’t see many photos of these in flight.”

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As the Cornell bird site notes about this species:

With dark gray upperparts and a neat white tip to the tail, the Eastern Kingbird looks like it’s wearing a business suit. And this big-headed, broad-shouldered bird does mean business—just watch one harassing crows, Red-tailed Hawks, Great Blue Herons, and other birds that pass over its territory.

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Reader Dom, who helped me track the source of many obscure quotations in FvF,  sent a mimic (I love mimics!):

I took this photo in a friend’s garden in Royston, just south of Cambridge.  It was a few inches from a nest of Lasius niger black pavement ants, that were swarming with flying males and females.  This is Myrmecoris gracilis [JAC: a “true bug”] and is a hemipteran.  In the British Isles it is, according to the best general insect guide (Michael Chinery’s Collins Complete Guide to British Insects), quite rare and confined to dry grassland in the south of England. If we can trust Wikipedia, it is found across Eurasia, & was named by the Finn, Rheinhold F. Sahlberg, who was from a family of entomologists.

Now the curious thing is that they are flightless – well, mostly.  So how do they spread?  It seems that some are macropteran or macropterous.  That was a new term to me but one I imagine you know – occasionally they produced winged forms which can spread.  There is a picture of a winged form here on the Encyclopedia of Life.

Ant mimic 1

You can find more photos of this bug here. The next photo, a closeup, is taken from ObsessedByNatureThe mimicry is clearly shown by the body shape, completely atypical of Hemiptera. It has an anty constricted “waist”, and a general, though imperfect resemblance to ants. But as we know, mimicry need not be perfect to be effective: all it must do to give an advantage is briefly deceive the predators or prey.

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Another photo by Dom:

Ant mimic 2

Dom also adds this question, which is a good one:

I am puzzled though by what advantage this insect gets by looking like a Lasius ant.  They are not stinging ants like red ants…

Well, there are many advantages to evolving to resemble an ant. One clue here may be that these things are predatory and feed on aphids. But I have no definitive answer for that question, and perhaps readers can weigh in.

Ant mimic 3

From reader A. M. Cournoyer sent an inaugural photo:

Antilocapra americana [pronghorns] seen in Bryce Canyon while cycling in the park.

Remember that pronghorns are not antelopes, and their closest living relatives are giraffes and okapis.

Cournoyer

10 thoughts on “Readers’ wildlife photos

  1. Once again, a whole post full of things I’d never heard of. Yes, even the pronghorn.

    It’s great continuing to learn every day.

  2. Even somewhat resembling a non-stinging ant should be an advantage, since ants taste bad to most predators are eschewed, not chewed. Many ant mimics resemble the pavement ant b/c these ants are very common. Predators will likely have already encountered them.

    1. Trout love to eat ants. (Also bees and wasps) On the San Juan River in New Mexico there are huge hatches of flying ants, and the trout sometimes eat so many that they die (presumably from an excess of formic acid).

    2. I think Mark is right in considering Myrmecoris a case of protective mimicry. Ants seem to be rather poor at distinguishing visual cues, and Myrmecoris does not prey on ants, making aggressive mimicry at first sight seem rather unlikely. Mimetic protection from insectivorous birds seems the best bet. However, Myrmecoris does feed on aphids, and it is possible that aphid-tending ants recognize poorer mimics and drive them away from the aphids they tend. It would be a good opportunity for a naturalist to conduct some experiments.

      A book I found (ref below) claims that immature Myrmecoris resemble small Lasius ants and the adult bug looks like the common red Formica wood ant! The resemblance may be defensive and either Batesian, if the hemipteran is edible, or Mullerian, if Myrmecoris are distasteful to their putative avian predators. If Mullerian mimicry, it is highly asymmetrical since the ants are very much more abundant than the bug. Lots of interesting possibilities, no?

      E. Wachmann, A. Melber and J. Deckert. 2007. Wanzen [Bugs]. Goecke et Evers, Keltern.

  3. They don’t call the Eastern Kingbird Tyrannus tyrannus for nothing. They typically perch on the highest, most conspicuous place, seeming to dare other birds to come close. From that perch they take off and return with an erratic, hard-to-track flight, catching insects over the creek.

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