Golden-ringed dragonflies

If I have a favourite dragonfly it is this one, the Golden-ringed Dragonfly (Cordulegaster boltonii). Large, spectacular and elusive, it is always a thrill to see one.

I have the privilege of helping to count dragonflies on the Hepple Estate in Northumberland National Park and last week Golden-ringed Dragonflies were the stars of the show.  The first I saw was by the Old Pond, a male patrolling over a small area and stopping frequently to have his photo taken.

With Richard Thompson, the estate ecologist and wild guide, I watched another male over the Bottom West Moor ponds.  It seemed to be patrolling rather than hunting and was frequently chased off by Four-spotted Chasers.  We moved on to the Bog Field and saw two Golden-ringed Dragonflies crashed in the grass.  Although they were male and female they weren't a mating pair and the male seemed to have the female in a headlock.

After a few minutes of stalemate he released her and proceeded to patrol the boggy field close by.

The female gradually recovered her dignity but rested for half an hour before flying off, apparently unharmed.

This short video was recorded on my phone from about a foot away and shows she was unconcerned by our presence.

I think the explanation for this episode is that the male was keen on mating and the female was resisting his advances.  In the last photo above the lower half of her abdomen is muddy so I think that she has only recently been ovipositing and wasn't ready to mate again.

The mud is intriguing because it suggests she had been laying her eggs in the waterlogged boggy field or in the pond.  Golden-ringed Dragonflies lay their eggs while bouncing down vertically into the muddy bottom in shallow water - described as being like a pogo stick or the needle on a sewing machine.

Both my guide book and the BDS website mention only rivers and streams as breeding sites for Golden-ringed Dragonflies.  However, last month we saw a female ovipositing in the Old Pond at Hepple (see photo below), I have previously seen a female in Slipper Tarn at Cragside (not far away), and this female was in a boggy area beside a pond.

I did manage to find one comment that the Golden-ringed Dragonfly "breeds in shallow peat runnels or seepages as well as lochs with exposed peaty muddy edges" and I think the Hepple Golden-ringed Dragonflies are breeding in still water as well.  I suppose the proof of this would be to find larvae in the ponds but that will be easier said than done.

A ruby-tailed burglar

Parasites seem to be dominant over hosts in the bee house this year.  I watched a mason wasp putting the finishing touches to her nest, blocking up the entrance with mud.

I wasn't the only watcher.  There were several ruby-tailed wasps waiting around.  They are cuckoo wasps and lay their eggs in the nest of other solitary wasps.

One in particular taking a close interest in what was going on.

Eventually the mason wasp was satisfied and after a last look round she flew away.

Within a few minutes the ruby-tailed wasp had returned to the nest and started to chew out the mud seal.

It took 25 minutes of chewing.

You can see her ovipositor is extended ready for action.

Then she suddenly turned around to lay her own egg in the nest.

That took only a few moments and she was off, perhaps to seek another victim.

As I understand it, the mason wasp lays a series of eggs in different cells along the length of the nest, separated by mud wall in the same was a a mason bee so I presume the ruby-tailed wasp, with a short ovipositor, can only parasitise the front cell.  I hope I'll be watching to see what emerges next year.

PS.  The photos are attracting a lot of attention on Facebook.  The experts on the BWARS page say the mason wasp is Symmorphus bifasciatus and the ruby-tailed wasp is likely to be Chrysis angustula.

Greenfinch?

Or not-so-green finch.  The greenfinch doesn't look very green in this company.

Yet another thing to worry about

It is a hard life being a solitary bee or wasp.  This season is turning out to be particularly difficult with poor weather and high levels of parasitisation.  The red mason bees have had an especially bad time this year (more on that to follow).

While I was watching the bee house the other day I spotted this shifty-looking fly, loitering with intent.  It wasn't one I recognised so I took its photo, planning to report it to the authorities.  It turns out to be Eustalomiya festiva, aka as the Sub-plumose Log Fly, an ID subsequently confirmed on the UK Diptera Facebook page.

On Steven Falk's Flickr site he says " E. festiva is fairly frequent throughout the southern half of Britain, becoming scarcer in northern England and Scotland.  It is typically found around dead and fallen tree trunks and log piles [of which I have plenty] in sunny sheltered locations in and around woodland.".  He goes on to say "The larvae are cleptoparasites of wood-nesting crabronid wasps such as Ectemnius and probably Pemphredon species", both of which are present in the garden.

I have reported it to iRecord and it is the first record for the north-east of England.  I doubt if it is rare here but there may not be so many dipterists in these parts.  Flies look really difficult and complicated so I am not tempted to become one.

Mrs Weasel on WeaselCam

Then it got interesting.  The next mouse was collected by a new weasel, a female I haven't seen before.  She is smaller than the two males and has brown toes and distinctive gular spots.

She seemed unfamiliar with the box and didn't know the routine with the mouse.  She eventually found it under the slate and took it away.

Less than 20 minutes later she was back and seemed convinced there was another mouse under the slate.  After digging for nearly two minutes she gave up and left.

She came back again for another look in the afternoon and took no interest in the slate this time but was more interested in the camera.  It will be interesting to see if she becomes a regular visitor or was just passing through.  At this time of year the full-grown kits are dispersing and this one might be intimidated by the two regular males.  We'll see.

Not so weasily recognised

The weasel camera box has been very busy since I started putting mice in as bait.  I was puzzled that "the weasel" would appear for a look around so soon after taking a mouse and part of the reason is now clear - there are at least two weasels. 

I put in two mice at once in my previous post and I can now see that the mice were collected by different weasels.  This is the weasel that took the first mouse last time (let's call him weasel 1). He has white front feet, particularly the left, which makes identification a bit easier as the gular spots (under-chin markings) aren't always clear. 

And this is weasel 2 with brown paws and who looks a bit bigger.  He took the second mouse.

And here are their gular spots, weasel 1 above, weasel 2 below.  Their flank markings are different as well.

Once I realised what was going on I have taken a careful look at the activity since then.  The next mouse I put out vanished without the camera being triggered.  My solution was to put the next mouse under a small piece of slate to slow the weasel down a bit.  And that has worked. Here is an example.  Weasel 1 (white paws) took the mouse, made a quick check that there wasn't a second mouse, and hurried away.

Just over an hour later weasel 2 (brown paws) turned up and could obviously smell the mouse but couldn't find it.

Here's the video.

And then it happened again.  Weasel 2 was just too late - this time only 15 minutes.  Weasel 1 came in and took the mouse, hurrying off with it, perhaps knowing there was another weasel around.

Fifteen minutes later weasel 2 arrived and could smell the mouse.  He searched for it before realising that it was gone and giving up.

Here's the video.

Over seven days there were 14 weasel visits, 12 by weasel 1 (who collected all three mice in that time) and two by weasel 2.

When I look back both male weasels 1&2 have been around for a while.  Weasel 1 was the first to explore this new box at the beginning of March.  And weasel 2 was the unlucky one I released from the rabbit trap at the end of March 

One other interesting observation is that there are now almost no visits to the box by mice or voles.  Both weasels can be seen scent-marking in the box so I expect it reeks of weasel and discourages potential prey.  Perhaps the smell of dead mouse puts them off as well.