06/09/2022 by Rebecca Hardy 0 Comments
The Incredible Water Strider
Water Striders also known as pond skaters, water skippers, Jesus bugs, or water skeeters, belong to the family Gerridae. Found widely across the Northern Hemisphere such as lakes, creeks, vernal ponds, and even mud puddles, water striders can often be found skimming the waters in the still parts of our Forested Wetlands.
Water Striders also known as pond skaters, water skippers, Jesus bugs, or water skeeters, belong to the family Gerridae. Found widely across the Northern Hemisphere such as lakes, creeks, vernal ponds, and even mud puddles, water striders can often be found skimming the waters in the still parts of our Forested Wetlands. They make quite the acrobatic moves to glide themselves across Ayers Creek. There are over 1,700 species in the very diverse Gerridae family, including scorpions and stink bugs, thus covering both aquatic and terrestrial habitats. Water striders are true insects, and not arachnids such as spiders. Water striders contain six legs compared to spiders that possess eight legs.
The thorax, or main part of a Water Strider is thin and oblong, averaging between 1.6 and 3.6mm long. Their 6 legs extend from their thorax. Their legs are their Houdini act, or secret weapon. Their legs have tiny hairs that repel water and capture air. By repelling water, its legs allow them to easily stand on the water’s surface and the captured airs allows them to float and move easily helping the overall buoyancy of the insect. These striders legs are so buoyant they can support up to fifteen times their own weight without sinking. Even in a rainstorm, or in waves, the strider stays afloat. Their legs are more buoyant than even ducks’ feathers. The front two legs, shorter than the rest are found near their mouth and used for rapidly grabbing and holding their prey and then uses its mouthparts to pierce the prey’s body and suck out its juices. The remaining four legs are significantly longer, are the ones responsible for allowing them to “walk” on water while also sensing water vibrations from prey. The middle legs act as paddles. The back legs are the longest and provide additional power, allowing the strider to steer and “brake.” Despite the strength of their legs on the water, their capabilities on land are very limited and practically useless.
Some water striders can fly while some cannot. All water striders contain wings, but the size and functionality in which they use them is not identical to others and is dependent on their habitat. But other species have wings only when they’re likely to need them. Called polymorphism, it is the mechanism that enables a parent to have one brood of young without wings, while the next brood has them. This allows water striders to be very adaptable to changing water and habitat conditions. A strider living in a small aquatic environment where temperatures are rising or habitat is likely to disappear has a mechanism that is triggered helping the next several generations of water striders to evolve its wings, allowing them to fly away and find a better suited habitat. Striders that live in lush, wet or expansive waters have short wings, as long wings could be easily damaged, take more energy to maintain, and are thus no longer needed. This capability allows striders to colonize all sorts of aquatic habitats, including tiny ponds and even mud puddles. If the habitat doesn’t last, the next generation has the ability to move on.
After a water strider has completed their five stages of metamorphosis, around two months a water strider is considered to be a fully developed and mature adult, capable of mating. Females tend to be twice the size of males. Males have been known to mate ad frequently and often as possible, whereas the females are a bit more reserved when it comes to mating, as it takes an expendable amount of energy to grow and lay her eggs. Females have a genital shield, that they use to block off unwanted suitors from mating with them. However, the males don’t take well to it. When mating, a male strider is on top. A male can tap the surface of the water, attracting predators. Since the female is beneath the male, she’ll be eaten first, and this is incentive for her to submit so that she can more quickly be on her way and avoid being eaten.
When it comes time for a female to lay her eggs, she will expel them anywhere they can easily attach such as substrate, rocks, plants, or any sturdy surface. About two weeks after laying her eggs, these eggs hatch, as long as the waters are somewhere around 77° F (25° C). Cooler waters may result in delayed hatching and development, while warmer waters may expedite the process. Water striders typically live until a freeze hits, with the adults dying and some eggs safely making it through the winter to hatch the following spring. If no freeze occurs, water striders have been known to live as long as a year.
Next time you paddle on Ayers Creek, try going left out of our launch into our Forested Wetlands. When the creek starts to narrow and the water becomes flat you’ll have the best chance of seeing them. Patience is a virtue in times like these. Enjoy the peace and quiet up into the headwaters as well.