Big migration time – September 2020

I never seem to get enough spare days to visit the Norfolk and Suffolk coasts during the autumn migration. This year is the same. On special days with northerly winds sweeping down the North Sea the skua migrations peak – I’ve missed the Long-tailed Skuas, (again!) caught the fringes of the Arctic and Great Skua (Bonxie) movements and may still catch the Pomarine Skua passage in October.

Big numbers of Arctic and Bonxies were seen heading south-west inland over Lynn Point/King’s Lynn on 25th September probably following the River Cam/Ouse valleys over the south of England at great height to eventually exit in the Bristol Channel. It’s a short cut route on their southerly autumn migration. In spring they have been seen flying north-east overland through the Great Glen short-cutting between the Atlantic and the North Sea on their way to their northern breeding grounds. Autumn skuas on the North Norfolk coast always seem to be flying west into the Wash not east to round East Anglia.

The dead Long-tailed Skua found last year along “The Backs” (probably brought down by a night-time Peregrine strike) is an example of this unseen overland sea-bird passage.

For me the second highlight are the autumn warblers especially seeing/finding Yellow-browed Warblers. They have become so frequent that they were unclassified as scarce migrants in 2017. With the Yellow-broweds will come other northern vagrants. Yellow-broweds have now become regular inland finds – two have been recorded in Cambrideshire already this autumn and one/two have been seen in our project area in autumn in the last few years. They seem to like sycamores and can be picked out by their penetrating distinctive call, a drawn-out “sooeeet“.

The third autumn passage highlight is new! It’s the overhead passage recorded on tape by Simon Gillings and Jon Heath in our project area of overflying night calls that are then identified to species and numbers of birds. Species recorded in August that are only rarely seen in our project area “on the ground” include Whimbrel and Grey Plover, Tree Pipit, Pied and Spotted Flycatchers.

The next night-time call we should all be hearing soon is the arrival of Redwings (the first in the County were recorded on the 27th).

Two groups of six plus eleven Common Buzzards were flying high in the thermals over the City on 6th Sept, on the same day at least two Chiffchaffs were in the Long-tailed Tit flock in Logan’s Meadow and two Water Voles were seen nearby. On 8th September at Hobson’s Park a Sedge Warbler was seen plus a singing Chiff and a Water Rail was heard and another seen. Chiffs were widespread across the City throughout the month. On 15th September a Whinchat was seen at Hobson’s (Ali Cooper, cbcwhatsabout.blogspot.com). Another singing Chiff was heard near Fen Ditton on 17th September and four House Martins were high over Eddington on 17th plus two confiding Buzzards.

Eddington is the best local site to see Buzzards, remarkable, considering they first returned to breed in Cambridgeshire in 1999 and are now common residents – probably our commonest raptor (good article by Brett Westwood on Buzzards in the August 2020 edition of British Wildlife magazine).

Water Voles at Logan’s Meadow (above)

The Bioblitz at the Botanic Garden on 19th produced 25 species of birds including a Nuthatch, two Grey Wagtails – one on the lily pond, the other a flyover – two Chiffs, a Sparrowhawk and a Jay peeling an apple! plus a late Swift on 17th during the bat search (Rhona Watson). Late September Swifts are rare. No Song Thrushes were recorded, where have they gone?

A Peregrine flew over Victoria Road Bridge on 25th and one was also seen over Castle Hill/Histon Road junction on the 26th. A Tawny Owl was hooting in trees near the doctors’ surgery at no1 Huntingdon Road throughout the month.

Two Crossbills flew over Trumpington Meadows on 22nd (Iain Webb, cbcwhatsabout.blogspot.com) and a Greenfinch was in my bird bath on 27th. Where have the Greenfinches and Song Thrushes gone? They were widespread in spring, located by singing territorial males but since then I have seen or heard very few of either species. I think it is predation of nests – eggs and chicks – by Grey Squirrels.

In contrast Long-tailed Tits are common and generate interesting multi-species bird activity in their roving feeding flocks. In Logan’s Meadow during the month I have seen Chiffs, (a Willow Warbler in August), Treecreeper, Great, Coal and Blue Tits, the occasional Goldcrest and even a Great-spotted Woodpecker swept along in the frenzy of the flock. It’s always worth looking through a flock of Long-tailed Tits. Last year at Paradise there was a Pallas’s Warbler in such a flock. Long-tailed Tits seem to have become commoner this year probably assisted by a mild winter and spring which helped over-winter survival.

At least 12 Meadow Pipits were at Hobson’s Park on 30th September and two Snipe were disturbed by the overhead air ambulance helicopter. Meadow Pipits have become Red Listed; they used to breed regularly on the NIAB’s Trials Ground, part of which is in our project area, but did not do so in 2019 and 2020.

There have been many reports across East Anglia this autumn of Great (White) Egrets in 1’s,2’s, 3’s and 4’s. It’s a bird of big open marshes and reedbeds and as big as a Grey Heron with a whopping long, often kinked, neck! Ten years ago, it was a rarity with occasional breeding in the Somerset Levels. It might show up soon at one of our open water sites: Trumpington Meadows/Hobson’s Park/Eddington/Cherry Hinton pits. Grey Herons along the City’s river banks have become very confiding. One catches fish at the end of a moored “Lets-go-Punting” punt by Jesus Green.

Bob Jarman 30th September 2020

bobjarman99@btinternet.com