Friday, 9 June 2023

Oslo odonate June 2023

Odonate (dragon and damselflies) are a frustrating group for me. Often you need to see them very close up to be able to identify them which means taking photos and then examining them when you get home which is not really how I like to enjoy nature. On the other hand there is lots to be discovered about their distribution as there are few people with an interest for them in Norway and I have recorded a number of range expansions. Dragonflies, are due to their size, easier to find, take photos of and identify and I can now identify most of the ones I find around Oslo with my binoculars in the field. Damselflies though are so small, and many so similar, that for the blue and green ones I am reliant on taking photos (if they ever stop long enough for me to manage a photo..)

I had a bit of a revelation a few years ago with blue butterflies that a number of different species could fly together and that it was a very foolish to just assume they were all the same species as the first one you identified (which was what I had been doing…). A couple of years ago it occurred to me that the same was also true with all the blue damsels that hovered around my feet and after taking lots of photos and pouring over the pc and books and websites I reached a new pinnacle in my knowledge when a couple of days ago I found out there were 4 different species buzzing around my legs (and I took all the photos from exactly the same spot!).

I have also found a male Broad-bodied Chaser that is holding a territory and this species does seem to have become established in Maridalen after the female I photographed earlier (and another I saw in flight). The Cambridge blue colour of the male is a colour after my own heart and this is my current favourite odonate.

male Broad-bodies Chaser (blåbredlibelle)

male Northern White-faced Darter (østtorvlibelle)

male Variable Bluet (fagerblåvannymfe)

male Arctic Bluet (nordblåvannymfe)

male Azure Bluet (sørblåvannymfe)

male Spearhead Bluet (spydblåvannymfe) which is the commonest species and also easiest to identify as it has greenish (lower) eyes

no problem with this one, a Large Red Damselfly (rødvannymfe)

this one is a lot more tricky and is a female Dark Bluet (klypeblåvannymfe). A male would be much easier to identify but I cannot find any this year and the site where they occur is becoming overgrown and may become unsuitable

I thought this was a dragonfly larve eating a tadpole but have been informed it is most likely a larve of a Great Diving Beetle (stor vannkalv)

I see many dragons and damsels emerging from the water after upto 3 years of development to only be eaten by a bird before they get to enjoy their final stage. This damselfly was captured by a spider straight after emerging. The spider is I believe tetragnatha extensa (gullrandet kjeveedderkopp)


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