Tuesday 28 May 2013

Bioblitz!

Last Saturday saw Bioblitz 2013 in Ireland: 4 locations competed to see which could record the highest number of species in 24 hours. The full story is at http://bioblitz.biodiversityireland.ie/

I was at Colebrook where we recorded 1086 species to top the list. My specialist areas were leaf-miners, micro-fungi and hoverflies, but most of us recorded whatever we saw during the day. I didn't manage to photograph everything I recorded, but this post contains some of the more interesting images.

Since I was 'doing' miners, I headed directly for the main wooded area and immediately found many mines of the weevil Orchestes fagi:

Mine of the weevil Orchestes fagi
A couple of things are worth noting about this miner. First, the leaves of beech trees have only been open for around a week, and the mine has already completed. The larva can only eat fresh leaves (when they are very soft) so no time is wasted when the leaves are unfurling. Second, most of our leaf mines belong to moths or flies, with a few sawflies making up the numbers: there are very few beetles that make mines. Finally, miners that make corridor mines (like the first part of this mine) are severely limited in size by the width of the mine and thickness of the leaf. Species that make blotches (like the final part of this mine) can grow to much larger sizes as larvae, and hence result in larger adults. Having said that, the adult weevil is only 3 mm. long.

Staying with weevils, here are two shots of another weevil: Phyllobus glaucus:


The weevil Phyllobus glaucus
The weevil Phyllobus glaucus
This is a feeder on broadleaf trees, usually near water. Thanks to Malcolm Storey for the id on that one. New to my species list.

While I was near the river, I also recorded a few microfungi on grasses and leaves, although nothing new to me.

I also found this stonefly, which appears to be one of the Perlodidae, but I don't have a key to get it any closer:

Adult Stonefly
Stoneflies are always found close to water, since the larvae are aquatic.

Another very fruitful area was the marshy area further along the river. This was a wonderful environment with dappled sunlight filtering down to an old pond. The fringe was surrounded by Marsh Marigolds:

Marsh Marigolds
And Skunk Cabbage, which is an escape:

Skunk Cabbage
Each of the plants is around 1 m. across.
New to my Species List.

Further in, I found the Green Tortoise Beetle, Cassida viridis:

Green Tortoise Beetle - Cassida viridis
The Cassida family of beetles are paranoid about safety: the larvae carry an 'umbrella' of dead skin and dung to ward off predators, the adults are 'stealth'-shaped in order to avoid casting shadows, and when they are flat to a leaf, present nothing for a predator to grasp.
New to my Species List.

The hoverfly Rhingia campestris has a tongue which folds and unfolds in a zig-zag fashion. When not in use, it stores it in the projection in front of its face:

The hoverfly Rhingia campestris

Solitary mining bees are very busy at the moment, stocking up pollen to feed their larvae. There are many species of Andrena, and this seems to be Andrena haemorrhoa, although it shows similarities to a couple of Andrena species that haven't previously been recorded from Ireland.

Andrena haemorrhoa mining bee

This Empid Fly had captured a specimen of Bibio marci:
Empid with Bibio marci as prey
Bibio sp. are known as St Mark's Flies because they normally emerge around April 28th. They are a month late this year.

Syrphus sp. hoverflies can be difficult to separate without a magnifying glass. This male has hairy eyes, which makes it safe to call it Syrphus torvus:

The hoverfly Syrphus torvus

Monday 20 May 2013

One sunny day

This year seems to be following the pattern of the previous two: once the frost is gone, we enter a period of extended rain and showers that lasts all the way through May and beyond. Any days with sunshine, therefore, are both welcomed by me and utilised fully by insects.

I have seen a couple of white butterflies on verges as I drove along, but this is the first that has settled long enough for a photograph. It's a male Green-veined White: the females have more spots which are also more pronounced.

Male Green-veined White
This is the first of this year's spring butterflies. These Green-veined Whites will have at least one further generation in July, and maybe another one later in September, but I rather suspect this will be a two-brood year given the lateness of the first. Just to keep things amusing, the second generation have more pronounced markings, with second generation males looking quite like first generation females....

The Speckled Wood is also rather late this year:

Speckled Wood butterfly
This is another butterfly that can have three generations per year.

Here's the underside:

Speckled Wood - underside
A couple of years ago, I was photographing fungi in September, and a Speckled Wood landed beside me on some fallen leaves. I turned to reach for the camera and when I turned back I couldn't see it, although I knew exactly where it was. It took me a good 10-15 seconds to see through the camouflage and get the shot.

Most of the 'regular' hoverflies are now present, although still in quite small numbers. This is the extremely common Melanostoma scalare, probably my most frequently-encountered hoverfly:

Female hoverfly - Melanostoma scalare
I still haven't seen a single Orange Tip butterfly this year. Last year I reported that someone had very carefully gathered every single specimen of Cardamine pratensis on the patch and left them in a pretty little 'posy' at the end of the hedgerow. I suspect the entire local population was wiped out at that time. I'm hoping that some mated female finds the couple of flowers that have opened this year and restarts them. The simplest act can have the most devastating effect.

Wednesday 8 May 2013

Heat at last

We had a couple of warm days and suddenly everything is moving.

Solitary bees dig private tunnels in soil where they lay their own eggs and bring back pollen to a store which will feed the larvae when they hatch. These nests are often grouped in 'aggregations' of tunnels where the situation is favourable, but each individual tunnel remains self-sufficient. The largest family is Andrena, where the females can often resemble small bumblebees. My favourite is Andrena cineraria, where the female appears to be wearing a Barbarians rugby jersey:

Female Andrena cineraria gathering pollen
Once the pollen has been gathered, the female will seal the tunnel and the larvae will hatch, eat the pollen, pupate and then hibernate until next spring. The species with the shortest season is Andrena clarkella, which feeds exclusively on Willow pollen, and most nests will already be sealed: this is a bee that can be seen for perhaps 50-60 days each year.

Staying with Dandelions, I spotted this 14-spot ladybird in the precise centre of one. this will give a good idea of scale:

14-spot ladybird on Dandelion

And an intriguing shot of an aberrant Dandelion:

Aberrant Dandelion
Dandelions belong to the Compositae, which includes Thistles, Daisies, Knapweed, etc. Each 'flower' is actually a composite collection of individual flowers, some of which are Ray florets (the outer ones), and an inner group of Disc florets. This specimen appears to have dispensed not only with disc florets, but also with the reproductive parts of the ray florets. I rather suspect that this is a genetic experiment that is doomed to be unfit for survival. All flowers on the same plant were identical.

The following shot shows just how late this year has become. I normally see Greater Stitchwort in late March, but this specimen is at least 6 weeks behind the usual date:

Greater Stitchwort

Lady's Mantle has a habit of not being there one day, and then being fully opened the next. When I was down taking a shot of the lovely folding leaves, I noticed a couple of other leaves waiting to be discovered:

a) Lady's Mantle b) Meadowsweet c) Meadow Buttercup
Flowers of the Lady's Mantle are at the lower left.

I wasn't expecting to see too many fungi at this time of year, but I found a couple of very old Polyporus badius on dead Snowberry:

Polyporus badius
And a couple of specimens of a Psathyrella which I think is Psathyrella spadiceogrisea. I'll do some microscopic work on these once the spores have been gathered:

Psathyrella cf. spadiceogrisea
Yesterday, I saw 3 species of butterfly in the garden. There were perhaps half a dozen Small tortoiseshells, a single Green-veined White and late on, a single Speckled Wood.

Small Tortoiseshell butterfly
The Green-veined White and Speckled Wood are this year's first butterflies, whereas the Small Tortoiseshells are actually last year's autumn brood which have emerged from hibernation. Orange Tip has to be next, since the Cardamine is out.

Bilberry has flowered, so perhaps we might see a Green Hairstreak or two in the next week or so:

Bilberry flowers

I was a little surprised to find Field Woodrush on the patch. I normally see Heath Woodrush, and maybe I have been ignoring these smaller specimens. One major clue to identification is the pale 'blob' at the end of each leaf:
Field Woodrush - Luzula campestris

Lastly for today, a few specimens of Green Alkanet were spotted on a verge at the side of a remote road:
Green Alkanet
These are garden escapes, but I cannot imagine anyone taking their garden refuse for such a distance in order to dump it. Maybe bird-sown.