Crawlies with Cri: Tule bluet damselfly

Tule bluet damselfly (Enallagma carunculatum)

Many do not know what it’s like behind blue eyes, but this week we’ll try to get some insight into what’s behind the particular set on the tule bluet damselfly (Enallagma carunculatum).
First: It’s pronounced “too-lay”.
Bluets comprise the Genus Enallagma and unsurprisingly are called bluets because the males, at least, are blue.
There are many blue damselflies who aren’t bluets but are blue. So, not all blue damselflies are bluets, but all bluets are blue – oh – except for the rainbow bluet who just has to be different.
It’s lucky that tule bluets sport such a bright shade of blue. They’d be very difficult to spot otherwise, because as damselflies go, they are very small, averaging just one and one-quarter inch in length.
Female tules are a light French gray, which explains why there are far fewer photos of them than of the bright-colored males. Older females will sometimes get bluish, but not the vibrant shade of males.
Tule bluets can be found throughout the northern states and along the West Coast. They can be found throughout Oregon, but the vast majority live along the west side of the Cascades. Isn’t that lucky for us?
Tule do require a specific habitat. They need slow or still water of any kind, so rivers, ponds, creeks or lakes. There has to be vegetation growing out of the water, preferably sedges or grasses.
Of course, they love their namesake tule. Here in Oregon we have two species of tule: hard-stemmed (Schoenoplectus acutus var. occidentalis) and soft-stemmed (S. tabernaemontani) bulrushes.
Fun fact: Tule bluets are usually the only bluet species that will live in marshes with heavy cattail growth.
Tule bluets have one generation per year. Females will lay eggs inside the stems of rushes emerging from water and the eggs will hatch in late summer or early fall and the nymphs will overwinter.
When the nymphs hatch, they get right to the business of feeding, chowing down on mosquito larvae, mayfly larvae and other small aquatic insect larvae.
Fun fact: The nymphs are slender with three leaf-like appendages extending from the end of the body which serve as breathing gills. They have a large, hinged lower jaw which they are able to extend forward with lightning speed.
The nymphs grow over the winter and into the spring, undergoing several molts. Sometime between early and mid-summer they’ll come out of the water, onto the rushes or grasses and molt into adult form.
This emergence typically takes about 90 minutes. Once they are able to fly, they’ll move away from the water and spend several days flying little, eating a lot and maturing.
As full adults they are also excellent predators, thus pest controllers, eating small flying insects including mayflies, flies, small moths and mosquitoes.
Adult tule bluets are on the wing into early November, so you still have a chance to see one darting around one of our slow or still bodies of water like little flashes of blue neon. If you’re lucky you may see one perched waiting to pounce on a mosquito flying by.