Sunday, 26 June 2016

Damselflies on the Leeds-Liverpool canal

Following my discovery of red-eyed damselfly on the Leeds - Liverpool canal the other day, I decided to do an impromtu survey today to try to get an idea of numbers between the footbridge nearest to Ramsdales hide and the footbridge near the bypass east of the flash. Conveniently this is almost exactly a 1km stretch of canal, or 0.66 miles if you're a Brexit supporter. Nothing particularly scientific about it, I simply walked along both sides of the canal and counted how many red-eyed damselflies I could see. They are one of the easier species to count due to their habit of sitting on lily pads.

In total I counted 72 individuals which included at least 10 pairs in tandem. Most of the lily pads are on the north side of the canal (i.e. the opposite side to Pennington Flash) so unsurprisingly the majority of the damselflies were also on that side.

Red-eyed damselfly, male and female in tandem.

Male and female red-eyed damselfly in guarded oviposition on a yellow water-lily.

No much else in the way of zygoptera on the canal today, except a few common blue damselflies. The pair shown here are in tandem. They are not mating, this is a form of guarded egg laying (oviposition). This pair have already mated. The female at the back is laying eggs under the water, while the male at the front stands guard by clasping her neck.

He's not particularly guarding the female, he's guarding his sperm. Even though they have already mated, the eggs are only fertilised when they are laid and the female can hold onto a males sperm for a day or two after mating before she decides to lay. This means that another male could also mate with her before laying, and in this case it may be the usupers sperm which fertilises the eggs. Therefore the original male guards her from other males and may actually induce her to lay becasue it's in his interest that she does not postpone!

Notice that this is the blue form of the female, many female common blues are green.

Fringed water-lily. These have much  smaller leaves than yellow water-lily.

Yellow water-lily has large leaves. Most of the red-eyed damselflies I saw were on the leaves of this species rather than fringed, but that maybe becasue they are easier to spot. on the larger leaves.

Great Orme

It's a good time of year to be on the Great Orme and there are really good numbers of silver-studded blue and cistus forester on the wing at the moment, plus all of the usual flowers putting on a great show.

Cistus forester

Cistus forester and common rockrose.

Common rockrose.

Grayling, not too difficult to see close up, but further away it gets a bit more difficult, it even replicates the orange lichen in the wing!

Female silver-studded blue.

The same photo zoomed in and cropped.

Male at silver-studded blue.

Saturday, 25 June 2016

Back for the Great Knot

With the great knot lingering in Norfolk for its second weekend we decided to have another try for it today. The weather was much better than on our first visit, bright blue skies and lovely warm sunshine, and the whole place looked that much better than it did last week. True to form the bird decided yesterday to change it's habits the day before the weekend and for the first time during in its stay it spent yesterday evening on the beach near Holme, which is where it was found first thing this morning. However the rising tide pushed it off the beach before we arrived and it flew to it's favoured roosting site at Scolt Head Island, about 5 miles to the east and just off Brancaster. It was a distant view at Scolt  Head Island with a few hundred red knot, but as the tide receded the flock spread out and came a bit closer and the great knot was one of the closest birds feeding in the water. Though still quite distant you could clearly see the dark mantle with chestnut scapulars and more particularly the black spotted breast which made it look very like a giant summer plumage pectoral sandpiper to my eyes. Also offshore here a few little and sandwich terns.

Then we moved to Titchwell  in the hope that the great knot might relocate there as the tide receded further, but unfortunately that never happened. Still we saw some decent birds at Titchwell, including 5 spoonbills, 1st sum little gull, red-creasted pochard, 250 avocets, 2 bearded tits and a nice selection of waders.

UK Life 414 (Great knot), Year 235 (Great Knot, Little tern)

Twitching the great knot on Brancaster beach.

NOT the bird I saw yesterday! In the absence of any photos from Scolt Head Island, these are great knot I saw in Australia last October. Unfortunately being in winter plumage they are nowhere near as nice as the Norfolk bird which is in summer plumage.

Avocet at Titchwell.

Titchwell. Black-tailed godwit and Knot in flight, with avocets in the bottom left.

Thursday, 23 June 2016

A couple of new damsels at Pennington Flash

Well for me at least! Yesterday I found a male banded demoiselle near Ramsdales hide and today two red-eyed damselflies on the nearby Leeds-Liverpool canal.

Banded demoiselle at Pennington Flash today, in the Himalayan balsam near Ramsdales hide. It's a species of unpolluted well vegatated reasonably fast flowing rivers and it occurs commonely at Sankey Brook in St Helens. I wouldn't be surprised if it's on the golf course at Pennington but I've never seen it there. It does wander a bit and can occur around lakes, e.g. I've seen it at Eccleston Mere and on Bold Moss where there are no rivers.

Red-eyed damselfly on the Leeds - Liverpool canal at Pennington Flash this evening. I've spent a lot of time over the past few days looking for them to no avail on the lilly pad covered pond at the back of the yacht club. This evening I was cycling along the canal and spotted a couple close in to the side on just a handful of pads. I find these quite timid damselflies and these are about the best photos I've ever managed of them.

There was a time when Leg O'Mutton dam in St Helens was the most northerly population on the UK west coast, but not any more because these are further north than Leg O'Mutton. However, they've probably extended their range a lot further north even than this in recent years so I'm not celebrating!

Apart from the eyes being red, they also look quite bulbous compared to the eyes of other damselflies.

Wednesday, 22 June 2016

Grey bulrush and a few other sedges and rushes from Pennington Flash

Really quiet for birds at the Flash at the moment, so I've moved my attention to other things.  Yesterday I had a look at some of the sedges and rushes that are growing around the small pond near the point at the bottom of Ramsdales Ruck. I was particularly interested in what initially looked like bulrush but on (much) closer inspection (i.e. under the microscope) turned out to be grey bulrush, a largely coastal species which apparently can be found at ex-colliery sites in the North West due a saline element to the seam. I don't know if this is due to something that they used to get the coal out of the ground or if it is naturally in the ground and has been brought to the surface and dumped with the slag but it's certainly resulted in enough salinity in the water to allow grey bulrush to grow.

Grey bulrush Schoenoplectus tabernaemontani.

This is a grey bulrush inflorescence or flower head made up of many spikelets.

This is a single grey bulrush spikelet under the microscope on 20x magnification. The spiklet is made up of several flowers or florets. In reality this is about 6mm long.

This is a single glume taken from the spikelet. Each floret has a pair of glumes at its base which protect the floret. Apart from being a generally greyer plant which is a bit subjective, grey bulrush differs from bulrush Schoenoplectus lacustris in that it's glumes are densely covered in small red spots. This is grey bulrush. Interestingly it is a sedge NOT a rush!

There were several other interesting rushes and sedges around the pond, including false fox-sedge Carex otrubae.

False fox sedge

False fox sedge

Not the cleanest of cuts, but this is a section of the stem of false fox sedge showing the classic triangular stem of a sedge. If it was true fox sedge Carex vulpina, the three "wings" of the stem would be a lot more pronounced.

A glume (the small scale at the bottom) under the microscope. The glume of false fox sedge has a green mid rib as you can see in the photo. True fox sedge does not show this feature.

Here are a few rushes from the pond.

Hard rush Juncus inflexus

Soft rush Juncus effusus

Jointed rush Juncus articulatus

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