Till death us do part?

Pond skaters, aka Water Striders, Aquarius sp., are so familiar to anyone who frequents streams and ponds that we rarely stop to look closely. And if we do, it’s not so easy, because they rarely stay still for long. Next time, though, especially in the spring, pause and observe. Here is what I saw some years ago on a Maine May day.

What first caught my attention was a strider with far too many legs:

On closer inspection it was clear there were two striders, one atop the other, mating. They skated around on the surface as one, and I realized there were other tightly bonded pairs in the same quiet backwater:

There didn’t seem to be any real action , and I didn’t see any pairs either coming together, or separating:

They use the surface tension to stay afloat, so the tip of each leg creates a sort of dent in the surface, and disturbs the leaf reflections in a magical pattern. The next picture not only has two courting couples, but one of the right-hand pair seems to be holding something.

When I got home, I started reading. Mating water striders stay conjoined for the entire reproductive season (!), which can be all the warm months. The male has no intention of letting another one displace his sperm, so he stakes out his female and there he stays. But after a while they get hungry, so they don’t hesitate to catch a passing insect and have dinner, as you can see above .

In France the same year I got a clearer photo of this romantic dîner-a-deux:

Trust the French to combine a little dalliance with an amuse-bouche.

PS Wikipedia has this fascinating description of how the two lovers hook up. (Water Striders are members of the Gerridae family.)

“Sex discrimination in some Gerridae species is determined through communication of ripple frequency produced on the water surface. Males predominantly produce these ripples in the water. There are three main frequencies found in ripple communication: 25 Hz as a repel signal, 10 Hz as a threat signal, and 3 Hz as a courtship signal. An approaching gerrid will first give out a repel signal to let the other water strider know they are in its area. If the other gerrid does not return the repel signal, then the bug knows it is a female and will switch to the courtship signal. A receptive female will lower her abdomen and allow the male to mount her and mate. A non-receptive female will raise her abdomen and emit a repel signal.”

Given the duration of the liaison, it’s a big decision. And maybe their system works better than Tinder, or indeed Bumble.

PPS Water striders are carnivorous. They often feast on insects that have fallen into the water and drowned. These ones are eating a dead dragonfly:

PPPS Their whole bodies are covered in miniscule hydrofuge hairs, which repel water, so they don’t get waterlogged and sink.