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Crawlies with Cri: Pacific clubtail dragonfly

Pacific clubtail dragonfly (Phanogomphus kurilis)

This week we’ll meet a crawly with quite an accurate common name. Meet the Pacific clubtail dragonfly (Phanogomphus kurilis).
Pacific clubtails can only be found close to the Pacific Ocean. The largest populations can be found in Central California, and right here in southwestern Oregon. There are spotty populations north to Seattle and there have been occasional sightings in Idaho.
The “clubtail” moniker is also accurate. The tips of their tails – especially the males’ tails – fan out into a club-like shape.
Of the 14 species of clubtail who live in North America, only a handful can be found in Oregon, making our Pacific even more special.
Pacific clubtails are tough dragonflies who can live and breed in a wide variety of habitats (as far as dragonflies go). Habitats that make the Pacific happy include: sand-bottomed lakes; rock-bottomed lakes; muddy ponds; large, swift rivers; slow, eutrophic rivers; and slow streams.
Larval nymphs do prefer a sandy substrate for overwintering, but they will make do in coarser fare. Depending on weather conditions and food availability Pacific will spend one or two winters as nymphs.
During that time they will eat lots of aquatic invertebrates including mosquitoes and other aquatic larvae. They may also eat small fish and tadpoles.
Adults will hatch out any time between April and July and will be on the wing from one to four weeks. The pictured male was defending his territory in early August 2022. We can tell he is “old” for a Pacific by both the wear and tear to his wings and his pale coloration. Young males will have bright lemon yellow or lime green faces and sides.
While many dragonfly species get darker as they age, Pacifics’ body colors become less vibrant. Their eyes, however, brighten from a gray-blue to the dazzling turquoise displayed by the pictured male.
Grappletail dragonflies look similar to Pacifics, but they have green eyes, not blue.
If you’re hanging out in the riparian, you’re most likely to spot a male Pacific. They spend their days defending prime breeding spots. The females live further from water, chowing down on a variety of other flying insects until they are ready to mate and lay eggs.
Pacific clubtails are strong fliers and siblings may disperse several miles from their original hatching site. Young males will often hang out closer together and further from the riparian area while they mature. Then the camaraderie period of their short lives ends as they disperse and start guarding those primo breeding spots.
At approximately two inches in length, Pacific are considered medium-sized dragonflies, but their bold colors and bolder attitude make them easy to spot. So keep an eye out for this brilliant and unique species this summer when you’re out and about enjoying our many lakes, rivers and streams.