Category Archives: Natural History

This Week’s Insects at Gunnersbury Triangle

Comma butterfly
Comma butterfly

Comma, Red Admiral, Small White, Meadow Brown, Holly Blue, Speckled Wood butterflies this week. A Cinnabar Moth, the first of the year, flew over the bank near a patch of Ragwort, the food plant of its caterpillars. Let’s hope she laid some eggs.

Tree Bumblebee Bombus hypnorum
Tree Bumblebee Bombus hypnorum
Macrophya Sawflies mating on Hogweed
Macrophya Sawflies mating on Hogweed
Bluetail Damselfly on Iris
Bluetail Damselfly on Iris

The first Bluetail Damselfly appeared today; Azure and Large Red Damselflies still about.

Honey Bee on Bramble flower
Honey Bee on Bramble flower

Small Skipper, Migrant Hawker and more at Gunnersbury Triangle

We had a lovely day down the reserve in the warm sunshine with a gentle breeze. We dug out an unwanted post with extreme use of pickaxe, crowbar and shovel, and thus refreshed did the butterfly transect. It found a Red Admiral, some Speckled Woods, wonder of wonders a Small Skipper (the second Skipper species this week), a Meadow Brown (not common here), and a Green-Veined White. Not a bad haul. And a lot of Peacock caterpillars, if those count!

Small Skipper
Small Skipper
Wasp Beetle
Wasp Beetle (Strangalia maculata)
Ladybird Larva
Ladybird Larva
Migrant Hawker
Migrant Hawker
Two-Spot Ladybird
Two-Spot Ladybird
Eat me if you dare - Aposematic caterpillars of Peacock Butterfly
Eat me if you dare – Aposematic caterpillars of Peacock Butterfly
Neuropteran (Lacewing) larva
Neuropteran (Lacewing) larva – note the forceps-like mandibles
'Marmalade' Hoverfly dorsal view
Macrophya sawfly dorsal view

Hot Summer’s Day Insects

Rose Chafer Beetle on Hogweed, dorsal view
Rose Chafer Beetle on Hogweed, dorsal view
amazing fly red abdomen black spots
amazing fly red abdomen black spots

On this lovely hot day, we tried to work, hammering in pegs to fix path edging poles. When we were all a bit dizzy from the heat and effort, we gave up swinging the sledgehammer and had a tea in the hut. Then we did a butterfly transect, which in the absence of anything but Speckled Woods, turned into a nature walk as we photographed all the other interesting insects. The Rose Chafer (on hogweed) is worth looking at full-screen as it’s very pretty.

A brown Shield Bug cf Coreus on Hogweed
A brown Shield Bug cf Coreus
Hoverfly Leuzozona leucorum
Hoverfly Leucozona leucorum
Array of Aphids on translucent Sycamore leaves
Array of Aphids on translucent Sycamore leaves

These aphids looked amazing with the sunlight streaming through the leaves; the leaves below were spattered with sticky sugar dropped by the aphids.

There was a beautiful Click Beetle too (like Athous haemorrhoidalis) but I didn’t photograph it as we were having too much fun making it go click and jump out of our hands.

Azure pair over Large Red Damselfly
Azure pair over Large Red Damselfly

See the Red damselfly? Look up: there’s a pair of Azure damselflies hovering above.  Well worth viewing full screen.

Great Tit feeding brood in Nest Box 10
Great Tit feeding brood in Nest Box 10

We were pleased (and somewhat surprised) to find a family of Great Tits in box 10, right beside the path, and not terribly high up either, but it was an old and presumably proven nest-site, and so it has proven again this year. I got a blurry photo of one of the proud parents entering the hole, which I had repaired with some aluminium sheet this winter.

Ovipositing pair of Azure Damselflies
Ovipositing pair of Azure Damselflies; female is the green morph

I was very pleased with this photo, with its surreal light and bubbles. I’ve not remarked the green female morph before: most Azure females seem to be a paler, more lime-green form.

China Mark Moth laying eggs on pond weeds
Brown China Mark Moth laying eggs on pondweeds

This last photo (taken at quite a distance) shows something very curious: the Brown China Mark, a micro moth that lays its eggs on pondweeds, scurrying over the surface of the water searching for suitable ovipositing sites. In the dazzling light, she was far more reflective than anything else, and I had to turn the exposure down two whole stops to get her about right. The larva is aquatic, feeding on pondweeds.

Not pictured: sawflies; a swift Ichneumon beside the pond (without a long ovipositor, but with a clearly clubbed abdomen); many bumblebees and striped hoverflies. Nests of Peacock butterfly caterpillars too.

Pond-dipping Day, Gunnersbury Triangle

Large Red (and Azure) Damselfly pairs ovipositing
Large Red (and Azure) Damselfly pairs ovipositing

Today I “manned the pond”, resplendent in my The Wildlife Trusts T-shirt complete with badger logo on a black background. I didn’t so much as “stand up for nature” as lie down, hoping that the rather lively toddlers waving pond-nets wouldn’t fall in. Their fortunately very quick mother asked me if any children had in fact fallen into the pond, and I replied truthfully that none had done so, so far. And somehow, they didn’t.

In the warm sunshine, the air above the pond was buzzing with Azure and Large Red Damselflies, some paired up and laying eggs, some males patrolling anxiously, chasing off rivals and presumably hoping for some more females to turn up.

The eager dippers caught lots of Greater Ramshorn Snails, and some smaller ramshorns too. Among the haul were some very small Water Boatmen, midge larvae in reds and yellows, water fleas, a tadpole or two, some mayfly larvae (very zippy) with 7 pairs of gills, and some little damselfly larvae (more placid).

Large Red Damselfly on Iris leaf; nice hexagons from camera shutter
Large Red Damselfly on Iris leaf; nice hexagons from camera shutter

Two Sunday volunteers, relaxed and jolly, joined in the pond-dipping: it turned out that the Conservation Officer was out on a flat roof trying to catch a mallard duck and her six ducklings. Unfortunately the duck escaped while they were trying to scoop up the ducklings, so the rescue was abandoned. If the ducklings can’t be got to a pond soon, they’ll starve as the duck has no other way of feeding them.

Queen Bufftail Bumblebee in Yellow Iris ...
Queen Bufftail Bumblebee in Yellow Iris …

We did carry out another rescue, however: a very large Queen Buff-Tailed Bumblebee was sitting exhausted on the boardwalk. We looked about for flowers, and tried her on a Yellow Iris, with some success; but she soon used up the energy its nectar provided. I suggested some sugar-water. This was fetched, and it seemed to have the right effect, as she perked up considerably.

Queen Buff-Tailed Bumblebee drinking sugar water
Queen Buff-Tailed Bumblebee drinking sugar water

Then, in between telling people about the ridiculously complex fertilisation system in damselflies and dragonflies (indirect fertilisation, sperm storage, yeah) and identifying pond animals, I tried to photograph a mayfly nymph with the absurdly limited depth-of-field of my macro lens. What with the white glare from the pond tray, the sun going into clouds, and toddlers leaning into the light to get a better look, it was somewhat difficult. Here’s what I got.

Mayfly nymph in a (fairly) clean pond tray, more or less correctly exposed and in focus
Mayfly nymph in a (fairly) clean pond tray, more or less correctly exposed and in focus

Newly-Emerged Birds, Butterflies and Damselflies

Driving in posts for wooden railing
Driving in posts for wooden railing

On a lovely May day, we replaced quite a bit of wooden railing, the rail mainly being fine but several of the posts having rotted at the base.

As we worked, a pair of Brimstone butterflies flew nearby, as well as a few Orange Tips, a Red Admiral, a couple of Holly Blues, and a Large White. It was very pretty among the cow parsley, green alkanet and garlic mustard, with visiting bees and hoverflies. A couple of brilliant metallic green Rose Chafer beetles flew over, just above the tops of the cow parsley.

Around the reserve, newly-fledged robins and jays were hopping about unsteadily.  A blackcap sang sweetly; a blackbird, a wren and some robins chattered in alarm from a thicket, mobbing a predator, apparently a magpie — most probably as it threatened to rob a nest of eggs or young.

Azure Damselfly pair choosing egg-laying sites together
Azure Damselfly pair choosing egg-laying sites together

Above the pond, Azure Damselflies and Large Red Damselflies were in cop and egg-laying (both species); up to three male Small Reds at a time were dashing about in tiny dogfights.

Free Public Event: Book Launch at Gunnersbury Triangle 17 May 2015

LWT reading by the author 17 May 2015
LWT reading by the author 17 May 2015

London Wildlife Trust have kindly put on a book launch event for my new book The English Love Affair with Nature. The event is free and open to all; though small children may prefer to eat the cakes and go pond-dipping, which will be available on the reserve! Attractions will include me, reading from the book; a chance to buy a signed copy, if that’s your sort of thing; nice things to eat and drink; and the beauty of a nature reserve in May, complete with birds, butterflies, bees, bugs, flowers and trees in new leaf, not to mention mini-beasts, newts and everything that wriggles in pond water! I hope to see you there.

Making Wooden Pegs (whatever next) … and a Congregation of Newts

Making Pegs (with a billhook)
Making Pegs (with a billhook)

Well, I’d read John Stewart Collis’ marvellous The Worm Forgives the Plough, and his description of the bill-hook as a marvellous tool, but it’s one thing to read about something and quite another to do it with a purpose.

Today, we were tasked with making edges for a stretch of path in the reserve. You can see some lengths of birch trunk lying along the path edge below my left hand. These of course had to be pegged to keep them in place, and then wired and stapled to discourage casual vandalism. The only source of wooden pegs was … more sticks. I set to work with the bill-hook, and indeed the tool is finely adapted to its job. Well-balanced, just heavy enough, and sharp, it slices through wood with a satisfying soft chopping sound. Even so, care and skill are needed, and the job takes a bit of time.

Congregation of Newts
Congregation of Newts

When I had made all the pegs anyone needed, I went for a little nature walk. Down by the pond a now-scarce visitor was singing in the birch trees: a Greenfinch. In the pond, several smooth newts were flicking and darting about. The sun was glinting off the water, as you can see, but it seems two magnificently spotty males were courting a drabber female at the top.

Snail Egg Pattern

Snail Eggs in Pond
Snail Eggs in Pond

Walking past the main pond, my eye was caught by a striking pattern reminiscent of a brain coral. Lying down on the boardwalk to get the diminutive lens of my phone camera as close to the pond surface as possible, the squiggles resolved themselves into long patterns of jelly divided mostly into hexagonal areolae like miniature cells in a honeycomb, each with a white boundary and a tiny yellow egg at its centre.

At the top left of the photo is a large Ramshorn Snail: several others were nearby, so they are the likely culprits. Generally pond snail egg masses (as laid by the large pointy-spiral pond snail Limnaea) are small, undistinguished jelly-blobs, so these large, impressive structures were a surprise.

Moths and Warblers at Gunnersbury Triangle

Early Grey Moth
Early Grey Moth

The dawn chorus at the reserve revealed two singing Blackcaps: one was alternately feeding on newly-emerged Cherry buds, presumably eating insect larvae, and giving short bursts of song or subsong. In a few days’ time the leaves will make such easy observation much less likely. There were two singing Chiffchaffs, one of them in full view in a Birch just coming into leaf above the main pond; and a Willow Warbler which I first heard yesterday near the picnic meadow.

Identifying a Pug Moth
Identifying a Pug Moth

A party of newly-fledged Great Tits blundered about the bushes on the steps by the main pond, and a Wren gave me a fine view at the ‘mangrove swamp’, which is fast drying up. The newly-dug extension to the seasonal pond has filled with water and is in fact deeper than the rest of the pond, probably a useful variation in depth.

Inspecting the Moth Trap at Gunnersbury Triangle
Inspecting the Moth Trap at Gunnersbury Triangle

Up at the hut, the moth trap was being opened after a night’s work. Inside were some Pug moths, probably Brindled Pugs, and a much larger Noctuid moth, an Early Grey.

Also seen were Jay, Magpie, Carrion Crow, Wood Pigeon, singing Dunnock, Blackbird, Robin, Mallard. A Wren was carrying food to its nest near the ramp.