Last spring while prowling through the footpaths in the Rattray Marsh, we came upon some other tiny hunters. They were gliding across some still half-frozen waters. We didn’t see them capture any prey. We did, however, enjoy watching their graceful moves.
When we got home, I did some searching for more information on Water Striders. The ROM has been digitizing some of its publications. This gave me the opportunity to read a little book by Lanna Cheng, published in 1970 titled The Water-Striders of Ontario. Almost all of the following article is directly attributable to this book.
Ms. Cheng says that Water Striders eat living insects and spiders that fall onto the water surface. I would imagine the hunting was poor on the day we visited. Almost no other insects were out and about yet. I’ll have to keep a closer eye on the fleets of Water Striders we see when we vacation. In the summer, there are plenty of insects to fall prey to these tiny hunters.
According to Lanna Cheng, the adult water striders survive the winter. That’s why as soon as some water thaws they appear. These photos were taken in March in the creek in the Rattray Marsh. Parts of the Marsh were still frozen and the water was still milky.
Apparently spring makes Water Striders feel frisky, because mating and egg laying occur in the early spring. Eggs are laid under the water on stones or vegetation, again according to Laura Cheng’s book. We didn’t observe any raunchy behaviour, but we’ll keep an eye out during future walks. For one thing, we’d be more successful in identifying the males and females if we could observe who was laying the eggs!
I had been hoping to identify our Water Striders but I don’t have enough information for a positive id. According to Lanna Cheng’s book there are at least 11 species found in Ontario. That’s far more than I expected. To add insult to identifying injury, Lanna comments that a group of Striders may actually include more than one species.
Some water striders have wings and can fly to new homes if their first watery home dries up. The wings explain how water striders can end up in swimming pools. (Again, credit for this information goes to Lanna Cheng.) So if a few drop in at your pool for an afternoon dip, you now know how they arrived.
Reading this small book made me realize how little I know about a creature that I see by the thousands each year. If the Water Striders were ducks, I think I would have made far more of an effort to learn what type they were, what they fed on, when they reproduced and how they moved about. It’s a reminder that I am guilty of “species-ism.” Suitably chastened, I will try better in the future.
- Things to Know about the Rattray Marsh in Mississauga ON
- The Water-Striders of Ontario, 1970. Lanna Cheng. ROM.
- What Are These Insects Walking on the Snow at the Oakville Ontario Marina in February?
Do you find Water Striders graceful or gross? Please share your experiences with a comment.