May 2020 Sightings

This month’s specials

On May 4th at 5.45am (Pam was watching!) the first of her Swifts returned to its internal nest box  and appeared on CCTV.  It had 4 days to wait before its mate appeared and an excited reunion was witnessed. All very astonishing, as they fly back separately from Africa.  A few weeks later, she reports a total of 8 nesting swifts, two eggs in the first nest; the drama of a fierce fight with a male intruder lasting 6 hours and one grounded swift, which misjudged the box entrance, hit a window, landed on the door mat and took off from the ground. (Apparently young strong swifts can do this – it’s the older, weaker ones that need re-launching.) Newnham’s skies are now filled with the screams of hunting swifts.  These early arrivals were picked up by Jeff on 4th, who later noted  about 100 swifts (with  ~10 House Martins) feeding in high winds over the oilseed rape fields along Grantchester Rd on 23rd.

Also in Newnham, there have been frequent daytime sightings of Barn Owls along the Meadows, including one sitting on the “Private No Mooring” sign post (Jill). Last month, I mentioned a scarcity of Collared Doves and others have agreed with this (Mary, Sue). However, they are present elsewhere (Lesley). On the other hand, it has been a bumper year for Cuckoos, which started at the end of March, went on through April and continued in May (15th in Skaters Meadow (Sandie), 20th and 27th in Newnham (Bob) and at 21st in Grantchester (Jeff)).

In Highsett, Leslie reports a Jay, and both Song Thrush and Mistle Thrush, thriving on the many snails in her garden.  Perhaps the same Mistle Thrush was seen by Sam the other side of the railway tracks. Jean witnessed her local female Blackbird smashing Banded Snails Cepaea hortensis, on the stone path. This thrush-like behaviour may perhaps have been provoked by the extreme drought through April and May, making earthworms inaccessible.

The hedges above Grantchester Meadows are alive with small birds and on 4th a Corn Bunting was singing, as well as the Whitethroats and Lesser Whitethroats heard earlier. Common Terns returned to the river from 1st May,  and Grey Wagtails were seen, along with Nuthatch and Tree Creeper at St John’s college (Sue, David). However, their most notable record was on 6th May when a Common Sandpiper was sighted by the river (David). A Cormorant (Jill) and Kingfishers were reported flying along the river.  Also there was an unconfirmed report of a Lesser Spotted Woodpecker earlier in the year at the Riverbank Club in Newnham – exciting if so, as they have become very rare (Ted).

The city Peregrines have at least one chick (Alan) and the second pair probably 3. One adult landed outside the kitchen window near Barton Rd (Veronica)!  Many thanks to all who reported their regular garden and wayside birds: tits and finches, thrushes and woodpeckers, corvids, swans and mallards, sparrows and dunnocks, warblers including Reed Warblers and Cetti’s Warbler along the Cherry Hinton brook. It is a tremendous year for Chiffchaff and Blackcaps! (Holly, Suki, Val, Maria, Bernie, Alec).

Lesley’s comment (April sightings) that there were fewer Moorhens around Jesus Ditch than usual led to a considerable discussion about chemical pollution, litter, predation, poor water flow, overgrowth of pond weed until….. 6-7 very young moorhen babies were spotted emerging from a nest (Alison). Hopefully, all is well after all.

Invertebrates

Maria report “Kissing flies” : the Signal Flies Platystoma seminationis (Platystoma means big mouth). A mating pair kept turning a complete 360 degrees on the spot, the female rhythmically moving her mouth parts up and down : they may also push their large mouthparts together (kiss!) as part of the mating behaviour. These flies feed on nectar and pollen and breed in decaying matter.

Ann discovered  Mullein Moth, Cucullia verbasci, caterpillars  munching the Verbascum. Veronica records large infestations of Brown Tail Moth caterpillars on a hawthorn hedge.  These caterpillars strip the young bushes bare and the webs cover the trees. Cockchafers are spectacular insects – David found one on the allotment in Trumpington.

Meanwhile, the ‘mothers’ have also been busy. Paul’s spectacular Puss Moth was followed by a Privet Hawk Moth, the largest native species. At the other end of the scale was Annette’s tiny (8mm) Tortrix Moth which came to the light trap in a Chesterton garden on 19th May. This is the first VC29 record of Phtheochroa schreibersana since 1920, and likely to be the first ever record of the species for the city. Also, lots of butterflies now: Holly Blues (David, Alec), Small Heath (16th), Brown Argus (21st) Common Blue (25th).

Odonata are now emerging by the day: a Four-spotted Chaser was first seen on 8th and the Banded Demoiselle (Jeff) are a constant delight through the summer at the Riverbank Club. Here are a selection of Duncan’s pictures.

Thanks for all the other pictures of invertebrates.

Vertebrates

Veronica says a young Grass Snake turned up in the pond and there were plenty of tadpoles, so it was presumably after the Frogs there.  This Riverside Toad seems to be surveying the traffic with some indignation, after a month of virtually none.

Veronica reports a Fox’s den at the bottom of the garden in Barton Close.  A litter of four young cubs play in the garden in the early morning until about 8am (presumably home schooling starts after that!)  For the second year in a row, they have dug up a bumble bee nest, but they do seem to have kept the Muntjac at bay, with more of the vegetables surviving. Colin saw Cat and Fox in a stand-off! – neither looks ready to back down. Mo was not so thrilled to have a Badger visiting her Trumpington garden.  Jill saw a very small Human child in the river edge, up to his waist, playing with and covered with squelchy mud.  Mother was relaxing and enjoying the scene – she, possibly the most impressive sighting of all!

Plants

In Hobson Park it is hard to know what survives from the original flora before the park was created and what has been introduced in the “wild flower” mixes and other plantings when the park was created. The area was intensively farmed before the park was created, so perhaps not much survived the annual herbicide applications.  This year looks good for Yellow-rattle (Rhinanthus minor) whose job is to suppress the grasses, allowing other plants to thrive.


In one of the ditches and along the W. boundary of the lake, Brookweed (Samolus valerandi) is in flower, along with a surprise – Common Cotton-grass (sedge) (Eriophorum angustifolium). It is considered to have been planted here, but interestingly, it is flourishing in presumably alkaline waters. Although a sedge, the stem is not triangular along the whole length. Swathes of Oxeye Daisy (Leucanthemum vulgare) are everywhere and there is plenty of Hemlock (Conium maculatum) in flower.

The botanists have been out and about. Chris found Whorl-grass Catabrosia aquatica on Ditton Meadows, Jonathan noted Common Valerian Valeriana officinalis on a wall in Brooklands Avenue (apparently last seen in the city in 1860) and Corn Spurrey Spergula arvensis by Queen Edith’s Way roundabout (last seen here in 2004). The first NatHistCam record (and the first for TL45 since 1997), Bristly Stonewort Chara hispida was found in one of the Adams Rd Sanctuary ponds.  The older pond has Chara virgata, so it is quite a good site.   

It has been a superb year for White Helleborine! Nearly mown down by the gardener at Murray Edwards College (Jo); in both the old and newer parts of the Beechwood Reserve and flourishing by the hundreds in Nightingale Recreation Ground (Maria).  They have been recorded there before, but as the pandemic has put the playground out of action, have not been trampled this year.

Last month mystery object was a germinating Mistletoe seed. The (virtual) prize was shared between Chris Preston, Janet Bayliss and Clarke Brunt. Clarke tells us, “The Blackcaps don’t usually carry them far before coming back for another one – sticking them to the same mistletoe plant as the seed came from is common”.  I hope for lots of suggestions for this month’s mystery object.

Mystery object