All posts by Monica Frisch

A report on our bird surveys

Winter Blackcap survey: Over winter 2016/2017 Blackcaps were recorded at 30 sites in the Cambridge NatHistCam study area. Overwintering of this warbler, which is mainly a summer visitor, is an urban phenomenon, encouraged by garden feeding and warmer urban temperatures. Ringing studies indicate these birds originate from southern Germany/Austria; the majority of this population join the UK birds and migrate south to north Africa to spend the winter but a small population migrate north-west to overwinter in the UK.

Breeding Rook survey: A count in March 2017 found 108 apparently active nests (AAN) at six rookeries in the study area and 111 AAN at the same six rookeries in March 2018. In 1959-60 there were 62 rookeries with 1158 AAN in our study area. The three largest rookeries in 2017/2018 were in the same locations as 1959-60; each with more or less the same number of AAN.

Mistle Thrush survey: Mistle Thrushes are a principal vector of mistletoe, the hemi-parasitic plant abundant in trees in parts of west Cambridge. They nest in March and begin singing in November of the previous year to establish breeding territories. Thirteen singing males were recorded; all were in the north and west of the city where mistletoe is most clearly seen.

Tawny Owls: A partial survey of Tawny Owls from the call of young birds disbursing from nest sites found four sites in the west of our study area and one in the east.

Beast from the west meets the beast from the east

Ravens were once vilified by sheep farmers as lamb killers that plucked they eyes out of their victims leaving them to die in agony. As a result, they were heavily persecuted. We now know they are mainly carrion feeders; Ravens around a lamb carcass are feeding on a still birth or after-birth. They are expanding their range from west to east and two recent articles in national dailies (the i-newspaper and The Times) have carried articles about this (“beast from the west”/”Black is Back”). Two to three pairs breed in west Cambridgeshire. They have been seen displaying, a tumbling/rolling aerial display, over Madingley and in February 2017 a pair were seen on the northern edge of our project area flying over Impington. This February a pair were seen heading out of Histon towards Oakington, just outside our study area. They are early nesters (February/March) and it’s likely these were young birds nest site prospecting.

The Rooks nesting at Girton College have returned to repair winter damage to their rookery – it’s the only rookery in the city using conifers to nest.

The city Peregrine that was shot last autumn and taken to the Raptor Foundation near St Ives is recovering but staff are unsure of its ability to hunt for itself. When the weather warms Sparrowhawks will begin their aerial displays; I guestimate 10-15 pairs across the City. The first year Kestrel on Coldham’s Common looks set to stay but the pair that had three young near the Darwin Green housing development between Histon Road and Huntington Road, which is now being built, will have to move on. The bird seen at Eddington may be one of these.


Golden Plover, Hobson’s Park  Peregrines return to City centre (see Olwen’s February blog)

Red Kite seen over Regent’s Street on February 20th (per Rhona Watson).

A Kittiwake flying south over Chesterton on 2nd March (Simon Gillings) is very unusual and could be just one of a bigger cold weather movement of this species.

Duncan’s photos of the Little Egrets on the Snakey Path from Brookfields (end of Mill Road) to Cherry Hinton Hall park are stunning – walk along the path and you may get the best views of Little Egrets you will ever see!

The edge of the Dickinson Pit at Milton Country Park just comes into our project area. There is a female Scaup there (found by Jon Heath). This uncommon sea duck was probably making an overland passage from west to east and back to its Scandinavian breeding grounds when it was stalled by the “beast from the east”.

A large flock of about 600 Golden Plovers were on farm land in the north of our project area on 12th February and about 150 Linnets on nearby stubble feeding on meadow grasses, mayweeds and groundsel that have been flowering and seeding over the winter. Two flocks totalling about 60 Golden Plovers also on Hobson’s Park near Great Kneighton (I always thought the “i” came before the “e” except after “c”!).

Six Siskins feeding on sunflower hearts in a Chesterton Garden in early December are still coming daily; the male has been singing – will they stop to breed? Blackcaps are toughing out the cold by staying close to fat ball feeders; one bird has been present during the cold period from 8:00am to 4:30 most days and sees off Blackbirds and tits but slips away when the Robin arrives. Female Blackcap seen over several days in John Street (Mary Seymour). The snowy silence was broken on Wednesday morning 28th February by a singing Robin keeping warm by the gas boiler exit flue!

The cold “Beast from the East” and settled snow causes real problems for birds approaching their breeding seasons. Fieldfares and Redwings have come into the city looking for remaining berries, cherries and crab apples but most have already been taken by resident Blackbirds. I have 12 records of territorial Mistle Thrushes – the Midsummer Common bird has been singing since November – Mistle Thrushes are also early nesters. Redwings will soon muster in numbers for their pre-migration gatherings. I have seen flocks in Cherry Hinton Hall grounds where they sing together as a chorus their curious subdued sub-song.

Fieldfares forced into gardens for food during the cold period Winter Blackcap staying close to its food source

A solitary Chiffchaff in Chesterton on 2nd March in a leafless street tree looked doomed in the freezing temperatures. Soon time for the first Brimstone butterflies.

Robert Brown of the Cambridgeshire Bird Club is surveying Grey Wagtails, especially breeding birds. They can often be seen by The Rush, the new cut across Coe Fen. Last years a pair were feeding young on the roof of the M&S building on the Market Square and a pair nested in the river wall 100m upstream from Magdalene Street bridge. Please send any records to him at:

5th March 2018

Bob Jarman






Egrets on Cherry Hinton Brook

Long ago it was a very rare event to see Little Egrets in the UK. But increasingly they are becoming commonplace and their numbers have increased dramatically in recent years. So it was no surprise as I jogged along Cherry Hinton Brook to find several of them hunting for fish near Cherry Hinton Hall. They are remarkably tame as well and will let you photograph them, as long as you don’t get too close.

Their numbers have been steadily increasing in France and they made the leap across the channel to breed in Dorset for the first time in 1996. By the start of the new Millennium they had reached 100 breeding pairs in this country and went on increasing in numbers. Now there are over 1,000 pairs. Initially birds visiting this country returned to France for the winter, but now they have become resident and can be seen throughout the year. The fact that they have colonised the city and are almost urban birds is rather surprising, but an exotic addition to our local fauna.

Their white plumage is not exactly what one would consider good camouflage for a hunting bird. But when you realise that the fish they are hiding from are looking up at the bright sky, white plumage is the perfect disguise. Their black legs are curiously ended with bright yellow feet. Does this give them some sort of advantage? Perhaps its handy to be able to see your feet in the murky water when wading.

Eventually they got fed up with me stalking them along the stream and took to their wings and flew away majestically.

Duncan Mackay 13/2/2018

Gulls, gulls, gulls

Gulls are difficult! Immature plumages, different winter and summer plumages, races within species, variation within species, recently separated species and several shades of grey add to the difficulty, or challenge, of identification. The majority of gulls in winter from Riverside to Jesus Lock are our “dead-bog-standard” Black-headed Gulls (without their black heads); numbers range from 140 to 270 depending upon the surface water on Jesus Green and Logan’s Meadow and the availability of worms brought to the surface. There may be a dozen Common Gulls and three or four Herring Gulls amongst them. Look out for Mediterranean Gulls; they have been seen two to three times in our project area. The most recent was a full adult, with Black-headed Gulls in August on wet grassland on the new Darwin Green development; it was probably a dispersed adult from a single breeding pair near Earith. Lesser Black Backed Gulls are mainly flyovers along the river BUT…… summer birds have been seen in the city centre suggesting they might be nesting on the rooftops!

Travel out of our project area to the Amey Cespa recycling plant at Landbeach/Cottenham Long Drove and the tip at Milton and the number of gulls and species and complexity of plumage variation increases. The following photographs taken over winter 2017/18 on Riverside/Jesus Green illustrate some of the plumage variations:

Typical Herring Gull Riverside

Adult winter plumage
Black-headed Gull, Jesus Lock

Unusual Herring Gull with Black-headed Gull, Jesus Green

Seventy-three Grey Partridges at Nine Wells is a spectacular count and 15 in two family coveys on farmland in the north of our project area; four Little Egrets near Long Road in December. Little Grebes are not common on the river, they used to breed on Riverside but increased use of the river probably disturbed them; one was seen in January and two pairs appear to be resident further along the river at Fen Ditton; three in the balancing ponds at Eddington on 4th February. A Great-crested Grebe on the river opposite Trinity College, dodging punts, in early January was unusual.

An oddly confiding Buzzard in College grounds on the 4th February appeared to be nest site prospecting. City Peregrines were seen mating on 1st February and then returning to a nest site – that’s got to be good!

Male Blackcap – James Littlewood Mediterranean Gull
Darwin Green 2014

Blackcaps continue to show; in addition to sightings in Olwen’s blog, birds have also been seen in Longworth Avenue, Tenison Road, Benson Street, Stanley Road and East Chesterton. Six Siskins have been daily visitors to a garden feeder in Longworth Avenue and a small group are regular in the Priory Road/Benson Street area off Huntingdon Road. Small groups of Lesser Redpolls have been seen feeding in the alders adjacent to the guided bus track near Cambridge Regional College and Cambridge North Station; they were in the alders in Green End Road but these mature trees have been felled; a flock of 35 Greenfinches in Storey’s Way on 4th February were unusual for a species that is on the verge of being Red Listed. The Bullfinch in Oxford Road in Olwen’s January blog is unusual; it had probably come into the warmer City, like the Greenfinch flock, for food.  Current research suggests Bullfinches pair for life which enables them to breed earlier than unpaired birds.

A Firecrest in Holly bushes in late January at a site in the north of our project area might just indicate a breeding territory (see blog, The Birding Account, January 2017), a Jack Snipe in the east of our area and townie Woodcocks are unusual waders.

So far only five Mistle Thrush territories have been counted in our project area; there must be more but their absence in Cherry Hinton could account for the lack of Mistletoe there.

The same adult Lesser-black backed Gull, showing how the light can affect the appearance of the grey back and wing colour.

Bob Jarman

The Birding Account: Winners and Losers

An excellent article by Paul Brackley in the Cambridge Independent (Jan 3-9th 2018) talks about how ineffective governance is a threat to biodiversity. He also mentions how targeted recovery programmes by conservation charities e.g. the RSPB and the Wildlife Trusts have helped rare birds re-establish thriving breeding populations. It got me thinking: what is Cambridge City’s balance sheet – winners and losers of breeding birds over the last decades? It is one of the questions our NatHistCam project will explore, but for birds the stories are reasonably well known.

The bird story is good: probably more winners than losers. Let’s start with the losers. The main losers are specialised woodland species which fits into a national pattern, not just Cambridge. Hawfinches which once bred in the Botanic Gardens and along the Backs are long gone. Lesser-spotted Woodpeckers (LsW), once our commonest woodpecker and in the 1980s often seen in Romsey Town gardens and orchards near Histon Road, are gone. So have Spotted Flycatchers which bred in Whitehouse Lane off Huntingdon Road and went when the Elms died from Dutch Elm disease. The LsW is  sparrow sized and may have died out from predation by Grey Squirrels or from the larger Great-spotted Woodpeckers. The Lesser Redpoll, a finch of cool northern pine forests, has gone; the last confirmed breeding in the City was in 2002. Nationally this small finch has withdrawn north and west probably as warmer summers have disrupted its insect food supply to chicks in the south of its range.

Our Rook survey has shown that numbers have dropped in the City by 90% since the 1960’s; rookeries along the Backs and in college gardens in west Cambridge have gone. Rooks are birds of open farmland and pasture and their decline mirrors the decline in numbers of many bird species in the farmed countryside. A major shift in farming from spring crops to winter crops from the late 1970’s ended the availability of over-winter weedy stubbles as a source of food. Our local Rookeries are now on the northern and eastern edges of our project area adjacent to neighbouring farmland.

Now for the plus side! Other corvids are doing well, probably due to less persecution. Most morning I’m woken by the belly-aching croaks of Carrion Crows. For several years a pair nested immediately above the Mill Rd/East Rd junction – probably the most polluted part of the City! After food fairs on Parkers Piece, up to 60 can be seen clearing the dropped food and takeaways (likewise early mornings). Magpies and Jays are now frequent garden visitors.

The Little-ringed Plover is an enigmatic species that colonises temporary wet sites around gravel and sand workings. It used to breed regularly in Cherry Hinton but the site became the David Lloyds Health Centre and a Holiday Inn Hotel. I recently heard birds over the Eddington development and it has cautiously re-established in Trumpington.

Grey Wagtails have become common across the City, not just near waterside habitats. I’m sure a pair raised young on the rooftop of M&S in the Market Square in 2017. Woodpigeons now breed commonly across the city (perhaps the countryside is too full of them!). They are one of the few species that can rely solely on vegetation to feed their squabs (or is it squibs!) and do not need high protein insect food to raise their young.

Little Egrets can now be seen across the city wherever there is open water or a stream. Another wetland species, the Cetti’s Warbler, can now be heard in the ditches in Barnwell in the shadows of Cambridge United’s football ground. The number of overwintering Blackcaps continues to increase. Lapwings attempted to breed on the northern edge of our project area, the first time for at least 50 years in 2017 and may do so again in 2018.

Common Terns can be seen feeding from Jesus Lock and Riverside to Horningsea from April to July; but where do they breed?

Lapwing at a potential breeding site at the north of our
project area

The real success has been in birds of prey, as Duncan’s photographs of Buzzards over East Road show. Peregrines were thought of as rare birds of rugged cliffs and haunted moorlands, but there are now more Peregrines breeding in our project area than on the Shetland Isles (2 v 1!). Buzzards have arrived in the last 15-20 years; they probably do not breed in our project area but certainly do on the very northern edge. Red Kites have successfully bred in our project area and may also account for the “eagle” seen in a Cherry Hinton garden! Sparrowhawks are now as frequent as they have ever been (they were extinct as a breeding species in Cambridgeshire from 1960 to 1985) and breed in the very centre of the City in college gardens. As an example of just what can happen if habitat is right, the area in the City boundary between Huntingdon Road and Histon Road (that is now being developed as Darwin Green) was left vacant for about nine years. In that period a big population of Field Voles established. Over-winter 2015/2016, up to four Short-eared Owls and over-winter 2016/17, a female Hen Harrier hunted over this area. In the past Merlin has been seen here. The problem is that alongside the presence of these wonderful birds of prey comes illegal persecution.

What of the future? Grey Partridges are holding on in the farmed margins of our project area with two breeding pairs in the north. But the population faces extinction in the south due to development near Nine-Wells. Stonechats may become breeders in the new country parks around Trumpington. Firecrests, might, just might turn up and breed; they like Holly bushes in winter and Douglas Firs to nest!

What have I missed?

Bob Jarman






Bob Jarman

December 2017

Kissing under the Mistletoe and all that!

The Mistletoe survey at the beginning of 2017 resulted in 122 records of Mistletoe in the NatHistCam area. The most common host trees are Poplars, Lime, Hawthorn and Apple. Mistletoes does not seem to like oaks; or perhaps oaks do not like mistletoe. These are visible locations and probably underestimates the actual distribution of mistletoe across the City; there are probably many more, out of sight, on garden hawthorns and apple trees. This is the next phase of the survey – to uncover the distribution in gardens although very little mistletoe has been found in the 21 gardens surveyed so far.

Please let us know if you have apple trees in your garden (and what varieties) and whether any of them have mistletoe growing on them.

The tree-top distribution of mistletoe is probably by thrushes, particularly Mistle Thrushes. In Chesterton I have seen a Mistle Thrush “hunkered-down” in a clump chasing off any visiting thrushes. The distribution in gardens maybe due to wintering Blackcaps. I have seen two male Blackcaps chasing off thrushes visiting a clump on a garden hawthorn then squabbling with each other over grazing rights! The birds wipe the sticky berries from their bills onto tree branches. Mistletoe seeds do not need any pre-germination treatment by passing through the bird’s digestive tract.

Mistletoe is a hemi-parasite – its roots infiltrate the host’s conductive tissue for water and nutrients absorbed through the host’s roots but the mistletoe’s green foliage actively photosynthesises. It is dioecious (“two-houses”) with separate female berry-bearing clumps and male pollinating clumps that produce no berries. Clarke Brunt has infected apple trees in the orchard at Milton Country park (on the northern edge of our project area) and says that aerial shoots of mistletoe appear after 3-4 months but its takes 2-3 years before significant growth is visible and the male plants produce pollen before the females bear berries.

Why kiss under the mistletoe? The two berries at the base of the leaf fork are supposed to represent male and female fertility. After each kiss, a berry is removed from the stalks; when the last berry is removed, the match for life of the kissing couple has been made. Mistletoe is the marriage matchmaker!

Mistletoe growing near Bethlehem, West Bank, Dec 2011 [below]
Mistletoe is associated with many superstitions especially in Nordic legends. In Christian legend, mistletoe was originally the crown of thorns forced onto the head of Jesus as he carried the cross through Jerusalem to Calvary. The Lord was so angry with the thorny rose bush that he transformed it into mistletoe – a flabby, parasitic, thorn-less shrub that grows at the tops of trees. The original crown of thorns (a Rubus bush) is supposed to grow only at St Catherine’s monastery in the Sinai but contemporary history says that it is a cutting from the original bush that grows in the Greek Orthodox archbishop’s garden in Jerusalem.

Berry bearing female clump, Chesterton, Dec 2017 [left]

Male mistletoe clump without berries Chesterton Dec 2016 [below]

Mistletoe is grown commercially in the fruit orchards of Kent and Worcestershire. Perhaps profits have reduced as  mistletoe establishes itself as wild plants but female berry-bearing clumps growing within easy reach in Chesterton seems to remain untouched.

Happy Christmas – under the mistletoe!
Bob Jarman
December 2017


More on Little Brown Jobs (LBJs) and Happy Christmas!

More on Little Brown Jobs (LBJs) and Happy Christmas!

Another Little Brown Job (LBJ) is the Redpoll (see December 2017 blog). It has a troubled taxonomic history. The species that breeds in England, Wales and (parts of) Scotland is designated the Lesser Redpoll. It has been separated from the Common Redpoll but in Ireland both “species” are considered the same – Common Redpoll.

Lesser Redpoll used to be a regular breeder in our project area; in spring displaying males could be heard in song flight over Romsey Town, Cherry Hinton and Petersfield. In 1989 a male was singing from the telegraph wires above Ridgeon’s wood yard in Cavendish Road. Within ten years it had disappeared as a breeding species in, not just Cambridge City but Cambridgeshire – the last confirmed breeding was in Coleridge in 2002, although a displaying bird was heard over Carlton Way/Gilbert Road in spring 2016.  A warming climate seems to be the reason this arboreal finch has receded north and west with a strong increase in Ireland. It is now a winter visitor to our project area and should be looked for feeding on Alder catkins – Newnham park play area and Milton Country Park near the apple orchard are good sites. It is a small Linnet-like Little Brown Job (LBJ) – the males have a red forehead (“poll)” and a black bib. It has a very distinctive flight call. Flocks may contain Common Redpolls which are paler with distinct whiter wing bars.

Siskins often accompany Redpoll flocks in winter and also feed on Alder catkins and visit garden feeders. They have distinctive yellow rumps and wing-bars. They breed in conifer woods, are common in the Thetford/Brandon Brecklands, but displaying males often linger in spring and singing birds have been seen in Cherry Hinton Hall park in late April.

Siskins in Chesterton
11-14th 2017

Another record of a single Stonechat from our project area – Trumpington, Country Park from Guy Belcher.

A walk along the Riverside will produce (Grey) Herons, Cormorants on the willows near Logan’s Meadow, possible Water Rail in Logan’s Meadow nature reserve, wintering Chiffchaff and Kingfisher (given away by its distinctive flight call – a loud “jeet”), winter plumage Black-headed Gulls and Green Woodpeckers often “grubbing” for ants.

Blackcap records for this winter period have come from Benson Street, Alpha Road and Longworth Avenue.