Friends of Cherry Hinton Brook

Little egret

Wildlife and plants along Cherry Hinton Brook

Cherry Hinton Brook is important for wildlife, providing habitats for a wide range of animals and plants that like to live near or in freshwater. It is a wildlife corridor, linking up different areas for wildlife, from the River Cam, through Coldham’s Common to Cherry Hinton, the chalk pits and Magog Down. This blue-green corridor contains many different habitats: from the river, streams and ditches to the fields and hills.

Chalk streams (a priority habitat under the European Habitats Directive and in the UK Biodiversity Action Plan) are a globally threatened and rare habitat. There are only a few hundred chalk streams in the world, confined to north-west Europe. The vast majority (just over 200) of chalk streams are in England. The water rises from springs at Cherry Hinton and is very clean and a constant temperature which is well-suited to many freshwater invertebrates, including riverflies, which Friends of Cherry Hinton Brook monitor, and dragonflies and damselflies. The number and variety of freshwater invertebrates is an indicator of the health of the stream.

The stretch of Cherry Hinton Brook running from Daws Lane, near Cherry Hinton Hall, north-west for approximately 1.7km before being swallowed by a culvert just past Coldham’s Lane, is a City Wildlife Site, as is the grassland around the Territorial Army Pit. A stretch of the Brook runs through the grounds of Cherry Hinton Hall, and part of the adjacent woodland is a City Wildlife Site.

Cherry Hinton Brook and the adjacent lakes are within the area studied by Cambridge naturalists between 2016 and 2020 and reported in the book The Nature of Cambridge (edited by Mark Hill, published by Pisces Publications, 2022).

One of the most important animals along the Brook is the Water Vole (Arvicola amphibius) as its populations have been much threatened by loss of habitats and predation by mink. See Water Voles. Mink are controlled in the Cam catchment and have not been seen along the Brook. But there have been occasional records of Otters which eat fish and were probably just passing through.

Muntjac foal

Perhaps more often seen are the Grey Squirrels, scampering about in the trees. These are not the native Red Squirrel but an American species which has outcompeted Red Squirrels which are no longer found in most of England. Muntjac, a small deer introduced into England at the start of the 20th century, are common in Cambridge and can be seen along the Brook. They are about the size of a medium-sized dog and produce a dog-like bark. Foxes may also be heard barking and are occasionally seen.

Rabbits are quite common and there are rabbit holes in various places along the bank. There are probably lots of small mammals: rats are occasionally seen, especially near Sainbury’s, various species of mice, shrews and bank voles. There are also bats which often feed on insects found along the Brook.

Well over 45 birds have been recorded along the Brook and from the adjacent lakes. The three lakes provide a prime habitat for waterfowl and are considered a site of ornithological interest (referred to as Cherry Hinton Pits) by the Cambridgeshire Birding Club. These large bodies of water are visible from a distance making the site ideal for migrating birds to use as a stopover. Tufted Ducks over-winter on the lakes while Great Crested Grebes, Terns and Gulls can be seen all year round. The Brook provides good hunting grounds for birds such as the Kingfisher, Heron and Little Egret which eat fish as well as for birds of prey. On the water, the most common bird is probably the Moorhen but Mallard are also frequent and Swans sometimes nest in the nearby lakes at Cherry Hinton Hall. There are also lots of birds that like hedgerows, such as Blackbird, Robin and Tits. SEE page Birdlife on the Brook for a checklist of birds often seen.

Grass snake

The Brook and Lakes are important breeding habitat for amphibians with large numbers of toads and newts migrating across Burnside to reach the water during spring in some years. Grass Snakes are seen in or beside the Brook occasionally.

The Brook contains healthy populations of fish, including Sticklebacks, Bullheads, Chub, Perch and Roach. A large shoal of chub live under the bridge which gives access to the lakes. The lakes are stocked with Carp by the Cherry Hinton and District Angling Club.

In summer quite a range of Butterflies can be found flying around or feeding on the hedgerows. These include Brimstone, Painted Lady, Red Admiral, Speckled Wood and Tortoiseshell butterflies. Recent studies have identified eight species of Dragonflies and Damselflies along Cherry Hinton Brook. Other easily-recognisable insects include bees, bumblebees and ladybirds.

The plants, especially the trees and shrubs on the banks of the Brook, provide feeding and nesting sites for many of the birds and insects and are also very attractive. There is a lot of Hawthorn with pretty white blossom in spring, Horse-chestnut trees also have showy flowers and produce conkers but are disfigured by leaf miners in autumn. Other common trees are Ash, Birch, Field Maple and Willow. Along the banks and verges grow plants typical of those habitats including Cow Parsley and Meadowsweet, while in early spring there are patches of Violets and an area of Coltsfoot.

The Brook supports a variety of aquatic vegetation, including species of Water Starwort, Watercress, Fool's Watercress and Lesser Water Parsnip. There is also the hybrid (Veronica x lackschewitzii) between the pink and blue species of Water-speedwell. Emergent vegetation includes a lot of several species of sedge, Common Reed, and Yellow Flag.