Tuesday, June 19, 2007

Black-Winged Damselfly

The Black-winged Damselflies are back. They've been delightful to watch in our yard. Usually we find them in the back since that's where the pond is.

The Black-winged can be more easily identified than many damselflies since it is the only one with solid black wings. There is some color difference on the wings between the male and female with the male being a darker color and the female being more brownish.

However, the best distinguishing mark to spot the females is a tiny white spot at the top of their wings as this photo shows.

Dragonflies and damselflies are not the male and female names for the same insect, which is what I thought for many years.

Damselflies hold their wings together over their back when at rest. Dragonflies generally have their wings spread. Another tip is that damselflies have elongated or wide heads, while dragonflies are rounded. The photo to the right clearly shows a broad head on the male.

These beautiful beneficial creatures begin their lives as nymphs in the larval stage, living underwater for a year of more. The aquatic nymphs of the Black-winged Damselfly are typically found in flowing streams.

If you look for them along stream banks, you will probably see a male defending its territory, since they spend much of their time within a small area throughout the day.

They choose their site for its suitability for egg-laying. Another consideration is a perch for the male to keep an eye on his territory. Maybe an overhanging branch similar to how hummingbirds defend their feeders and flowers. Damselflies feed on small flying insects like mosquitoes and gnats, which they catch in flight.

The male will even defend his territory from other species and especially other males. Damselflies mate on the wing in the same unusual fashion as dragonflies and after mating with a female he will immediately return to his perch.

The nest is just below the water's surface on some type of stationary debris to which the eggs will stick. They hatch in about 7 days and the nymphs swim away to feed. As I've been playing around in the pond with a little tea strainer I've caught several of the larvae and was able to get the magnified photo of one of them while it was still in the strainer.

This is the first time I've seen this in our pond and after identifying what it was I was very excited. Our little habitat at Bluebird Cove gets better every year. It's wonderful to see things balance themselves out.

The nymph will molt from 6-15 times before emerging into what we see flying around. The last stage crawls out of the water onto vegetation before the adult emerges. Most species have one generation per year. Adults emerge spring, summer or fall and live from a few weeks to a few months. Seems like such a short time for such a beautiful creature, but that is similar to butterflies also.

Adults feeding on flying insects are very effective at reducing mosquito populations in the air while nymphs eat mosquito larvae in the water.

Like most of their adult behavior, the feeding ritual is very interesting. They will choose a place to perch that is directly facing a sunny area. When another insect flies into the area, the damselfly will speed out and catch it in flight with its hairy hind legs, and then return to its perch to feast on it by chewing.

Fortunately we're able to watch this from our breakfast area window which seems to be a favored spot for them since there are plenty of bushes and stair rails and posts. It's also not very far from the pond.

Ponds provide an added habitat feature to your Backyard Wildlife Habitat. Ours is only about 4' wide by 8' long but it has been busy since a few months after we completed it.

We were blessed to have Charlie Allred help with the pond project. He was the one who "paved the way" for the one we had in Alabama.

Charlie is also known as "The Butterfly Bench" man since he made the steel butterfly bench for us which has been a major attraction here at Bluebird Cove.

We've got a lot of wings fluttering around here .... if you get near Central Virginia, remember you're welcome to come sit with me on the butterfly bench and take a walk-about. Until then, maybe you'd like to see some recent critters and blooms of Bluebird Cove.

No comments:

Share This Post