September 2021 Sightings

A Quiz!  Here are 4 caterpillars – whose are they?  (Here is one of many helpful Ids to caterpillars: https://www.naturespot.org.uk/gallery/moth-caterpillars).  Answers at the end.

Beginning with plants for a change, a visit to Mill Rd cemetery turned up some Ivy Broomrape – a parasitic plant which lacks its own chlorophyll.  We also found Wild Clary there. One notable botanical record :  Alan Leslie found a single plant of Chenopodium glaucum (Oak-leaved Goosefoot) on disturbed ground created by the construction of the new cycle path across Coldham’s Common.  This plant is rare in the county.  The forced absence of volunteers during the Covid pandemic has led to an unwelcome resurgence of Himalayan Balsam along the main drain at the north of the Common.

Ivy Broomrape Paul Rule

Bird news is very scanty this month. The last Swift was reported on 11th and Swallows not at all. Chiffchaffs have been widespread and singing across the City up to the middle of the month (Bob). Holly reports small birds in feeding flocks in Cherry Hinton: Long-tailed, Blue and Great Tits, Goldcrests, House Sparrows and Goldfinches. Rose spotted a Barn Owl flying over Trumpington Meadows and I have seen one over Skaters’ Meadows in Newnham, quartering the meadow in late afternoon sunshine.  Rooks and Jackdaws have returned to Paradise Island winter roost, but numbers are well down on a few years ago.

Richard reports a single Swan Goose on the lake in Hobson Park swimming along among the (numerous) Greylag Geese. According to Wiki (https://en.wikipedia.org/wiki/Swan_goose), this bird is native to the Far East, but escapes are not unusual amongst feral flocks of other geese and goose hybrids are also common.

Odds and ends: Simon reports a Pipistrelle Bat (around 50kHz) flitting back and forth at head height for several minutes by the house and managed to photograph it: a lovely “x-ray” against the night sky.  A Badger in Peterhouse might explain why the College’s Hedgehogs seem to have disappeared (Justin). Peter saw a Grass Snake swimming at Byron’s Pool – there have been an unusual number of sightings this year. John found a lovely specimen of Chicken of the Woods Fungus, growing on Hazel at Churchill College.

Ben sends pix of Heriades truncorum or Large-headed Resin bee, which was using holes drilled into an old post. It collects resin from pines to seal the cell partitions, combined with grit/bits for the final plug.

Several references to Ladybirds: Monica found a 22-Spot sitting on a water butt – apparently it is unusual in being a mildew-eater.  Val had a plague of Harlequins and was single-handedly trying to eliminate them from the UK by squashing each one. Our trip to Mill Rd Cemetery turned up a Harlequin and also a 10-Spot – both highly variable species.

Some late butterflies in Logan’s Meadow included Painted Lady and Speckled Wood (Bob). Mo found Common Blue, Red Admiral, Comma and Peacock butterflies at Trumpington meadows. There are still Dragonflies on the wing (Rhona) and Paul got excited about an Ornate Shieldbug, possibly a first record for Cambs. This is yet another species fairly new to the UK. It is expanding its range northwards and most records are from coastal areas.

Ionathan’s moth trap continues to turn up surprises.  A Dewick’s Plusia and a Clifden Nonpareil (Blue Underwing) were this month’s specials. The latter became extinct in UK in 1960s, but appears to be creeping back again. Its larvae feed on aspen and poplar.

Answers to the Quiz: 1  Grey Dagger Moth (Eve); 2  Knot Grass Moth (Mark); 3  Elephant Hawk Moth caterpillar (Mo); 4  Pale Tussock Moth (Sam).   The Knot Grass moth caterpillar was on Spurge, apparently not affected by its toxins.

Olwen Williams    olwenw@gmail.com