Insects Emerging Late in May
Category Archives: Natural History
Hybrid Swarm of Oaks at Gunnersbury Triangle
Pondlife and Mating Insects after Spring Rain
Since our Hawker Dragonflies (Migrant and Southern Hawkers) fly later in the year, we think this exuviae (cast skin) has survived the winter. It may have been hooked on to a plant just above the waterline, and only fallen into the pond with recent disturbance.
Sawflies look quite wasplike in their black and yellow, but have no narrow “waist” at the base of the abdomen – they’re pretty much the same width all the way along. All the waisted Hymenoptera evolved from Sawflies.
We’ve now seen three Roman Snails in different parts of the reserve, after none in the past few years, so either the weather has brought them out, or more likely someone released their pet snails when they no longer wanted them. As the name suggests, the species has been in Britain since the Romans, who introduced them for food. We’re happy to see this handsome species here, but all the same it does constitute an introduction to a nature reserve…
Spring Surprises
Spring arrives in Gunnersbury Triangle!
Spring has arrived, with Orange Tip, Brimstone, Holly Blue, Comma, and Small White butterflies all flying today.
We’re racing to finish clearing the brambles along the edge of the old railway track where we hope to have some neutral or even acid grassland on the railway shingle. Time is against us now, as the warm spring weather and gentle winds have brought the warblers in. Today the first Blackcaps of the year sang in the reserve, along with Chiffchaffs, Wrens, Robins, Dunnocks, Great Tits, and Blue Tits, not to mention the chattering Magpies.
Among other animals celebrating the spring are the foxes, which have made many new holes and can often be seen about the reserve if you come along and sit quietly in the morning.
The wild Cherries are in flower all around the reserve, and the Pussy Willow catkins are glowing golden in the sunshine.
Bufftail Bumblebee queens seem to be everywhere, it being hardly possible to reach down for a bramble or a twig without disturbing one.
I was pleased to uncover two fine Birch saplings, just coming into new leaf, that had been hidden under the brambles.
Patrick found a buried milk bottle. We wiped the earth off it and held it up to the light: it read “Golden Seal” in raised curly ‘handwriting’ lettering. The brand vanished in the mergers of the 1970s as dairies grew bigger, so the bottle must have lain undisturbed for perhaps half a century, from before the Triangle became a nature reserve.
Day-flying Orange and Yellow Underwing Moths
Netty is away so Katherine led the group to, yes, clear some more brambles. We do occasionally do other things, actually. It was pleasantly warm with bursts of sunshine, and we dug out one champion bramble root after another. The ones down here are far more deeply-rooting than those on the bank, have few stems and basal shoots, smaller ‘briar’ root lumps, and much thicker stems. In short, they are the monsters of the bramble world, and sometimes seriously difficult to dig out. It’s easy to believe these are a different microspecies from those up on the bank: there are around 100 microspecies known in the Rubus fruticosus aggregate. It would be fascinating to hear about the genetics of our local bramble populations.
Katherine managed to photograph two Underwing moths:
The two species both have brilliantly coloured underwings, concealed at rest under the cryptically coloured (well camouflaged) forewings, but revealing a flash of bright contrasting colours when they take flight. This is often enough to startle a predator, giving the moth a moment to escape. Curiously, these two species are in different families: Noctua janthe is a noctuid, while Archiearis parthenias is a geometrid. This implies that the trick of having a bold yellow/orange/red stripe contrasting with black has evolved separately at least twice among moths (the same sort of thing happens also in some grasshoppers), an instance of convergent evolution. In other words, if it works, invent it again. N. janthe is common everywhere, while A. parthenias specifically “flies in sunshine around tops of birch trees in spring before leaves develop” (writes Chris Manley in his marvellous British Moths and Butterflies), exactly the case here today. Dial up the right ecological conditions, and the species appear, often.
Toad Time
It was a good day for amphibians all round, as we also saw a pair of Smooth Newts in amplexus in the pond. I didn’t get a photo for the good reason that unlike the Common Frog, they remain elusive and well-camouflaged at the bottom of the pond. And the frogs were still going at it full throttle, with around 20 splashing about beside the island.
Frogspawn Time!
Nectria cinnabarina – a tiny fungus on wood
Storm Doris is blowing a gale today, but in between the showers and racing ragged clouds was a fine half-hour of warm sunshine, the daffodils glowing yellow. A cut twig caught my eye in the brilliant light, speckled with tiny spheres, the pinkish fruiting bodies of the Ascomycete Nectria cinnabarina, a small saprophytic fungus, also called Coral Spot.
Giant Polypore Bracket in Richmond Park
