Sunday 7 August 2016

Habitat, habitat, habitat

As mentioned in my previous post, the reason for the trip to Graemsay was to ascertain whether there were any dragonflies or damselflies present and, if possible, confirm if there was a breeding population (as opposed to fly-ins from neighbouring Hoy).

During earlier visits outwith the flight season, I had reasoned that an old flooded quarry, located between East Hill and West Hill, was the most likely spot where a small colony might set up home. When it comes to wildlife, habitat is all.

On the walk from the pier, wending my way across the island, I must admit that I did notice a few other potential sites of odonatological interest. It's funny how you never really know somewhere until you've at least plodded round it, putting one foot in front of the other. It must be something to do with the slow pace allowing the time to notice things, which would be rendered invisible with any other mode of transport.

There are some burns running off the moorland that have definite possibilities. Could Golden-ringed Dragonfly inhabit these water courses? Of the dragons in Orkney, Golden-ringed is the only one that breeds in moving water.

But onto the quarry itself, much fuller following recent rain, but tucked into a low hillside and providing some shelter from the weather.

This is the view looking west to the Hoy hills.

And this is looking south-ish, from the shallow (and most interesting) end.

So, what did I find?

Well, almost immediately I spotted two Blue-tailed Damselflies, as they were sat conveniently on a very obvious rock.

And after a bit more searching, I found a third Blue-tail.

I think that these are all males, which isn't really the correct gender mix for a breeding population (though in certain parts of the world, species with all female colonies do exist - parthenogenesis, it's called). So no ladies present that I could see, and no exuviae either. This latter point (the empty larval skins) is the usual means of confirming breeding on site.

Not to worry, here's a close up of one of the boys...

And also a small bluey-hued bug of some kind...

As Johnny Nash, and also The Emotions, sang "There are more questions than answers".


Sian said...

The little bright blue insect seems to be a mystery. It looks very cute, I wonder what it is? And delighted you found male damsels (er I may have questions about that!) on Graemsay. I will share the photos and tell people to look out for them - with binoculars....and magnifying glasses....and that these photos aren't true to life size..... but whizzo none the less!

Imperfect and Tense said...

Male damsels... not so much Danny La Rue or Widow Twankey, but maybe more Lola from Kinky Boots