August sightings 2020

This month’s specials

August – a month of comings and (mostly) goings: the city has been full of migrants going south. Aggregations of Swifts, House Martins and Swallows have been reported, with swifts even up to the end of the month.  On two occasions, Jeff noted a single Noctule Bat feeding with the flock of swifts and martins.  He also reported a Common Redstart female along Barton Road, a Spotted Flycatcher and a Whinchat in Newnham.

Tawny Owls have begun calling again in Newnham (Pam), Jesus College (Rhona) and around Histon Road Cemetery (Lesley). Corvids have been coming together in Newnham as well, about 30 Jackdaws and a few Rooks in the evening. The mass arrival of these wonderful birds always signals the end of summer for me. Peregrines (Ben) and Sparrowhawks (Eve) have also been reported. Rhona sent a picture of a baby Stock Dove – one of Jesus’s many residents.

Trumpington Meadows continues to excel. As well as the Small Blue and Small Heath Butterflies, there have been several Clouded Yellow Butterflies there (Mo). Also carried on the warm southerly winds were day-flying Jersey Tiger Moths (Paul).  Gypsy Moths which had been extinct in East Anglia since the early 1900s, are turning up again in small numbers (Paul).

Duncan reports the transition from summer Odonata species to the start of the autumn ones. For the most part, Emperors and Black Tailed Skimmers have gone and Ruddy and Common Darters and Migrant Hawkers have arrived, together with Willow Emeralds. At the start of August there was a huge influx of Lesser Emperors and Southern Migrant Hawkers. Jeff also had a good number of sightings of damselflies and dragonflies, including a few Small Red-eyed Damselflies at Thompsons Park, together with a Black Tailed Skimmer.

 Rhona reports a Seed Beetle Bruchidius siliquastri which is fairly new to Britain. Another probable Cambridge first is the Hot Bed Bug Xylocoris galactinus (!) found in a (very hot) compost bin (Paul) (above). These are tiny predatory plant bugs that like compost.  Other contributions from Paul are a ménage à trois : mating Speckled Bush Crickets with a second male who tried to butt in, but was a bit too late. Then a stunning and quite scarce Gall Fly Merzomyia westermanni found on its food plant, ragwort, at East Barnwell NR and a Blue Shieldbug at Byron’s Pool. He also reports a couple of Spiders from his now famous garden: a Comb-footed Cellar Spider Nesticus cellulanus and a small orb web spider Gibbaranea gibbosa. While neither are particularly rare, these are new records for Cambridge, which is under-recorded for spiders (anyone want a project?!)

Maria saw what she thought was a ladybird pupa, until it walked away! 5mm and very spiky, it was on a thistle in Worts Causeway and turned out to be the larva of a Tortoise Beetle (Cassida sp, probably Cassida viridis). These larvae have twin tail spikes (the anal fork) at the end of the abdomen which they use to carry a faecal shield on their back. This is composed of its frass and bits of old exoskeleton. It is thought it may be used as camouflage or possibly for defence, as it can be raised and lowered and even swung.  (Superb pix Maria – better than anything on line!)

Otters have been travelling up Cherry Hinton brook and fishing in the Cherry Hinton fishing lakes (Duncan). Some large Carp have been taken. This probably explains why Otters have not been seen in the middle of Cambridge this year – they have found a better food source. Also in Cherry Hinton was a Rat near the children’s sandpit by the stream (Val).

Pam and Mary have both found it a good year for Frogs and I’ve also had lots of baby frogs in the garden. Is the tide turning here?  Hopefully they will be feeding the Grass Snakes such as those seen in Storeys Way and Fulbrooke Road (Jill).

And finally, Pam recounts the argument between a couple of foragers, who were busy attacking Paradise’s latest large Chicken of the Woods Fungus and a passer-by who felt they were spoiling its beauty for others.  She angrily defended her right to wild food!

Olwen Williams