Wildlife watching on Brownsea Island

A willow warbler perches in a green-leaved tree — Willow warbler | © National Trust Images/Nick Upton

As well as red squirrels, there is plenty of wildlife to see all year round and things change with the seasons. Take a walk through the woodland or down to the lagoon, and don’t forget your binoculars.

Spring wildlife

The island is a hive of activity in spring, with a changeover in visitors on the lagoon, we say goodbye to species that have overwintered here and we welcome those who will stay for the summer to nest and raise their young. Early butterflies are on the wing and red squirrels are active feeding their young.

Birdwatching on the lagoon

Look out for common and Sandwich terns who nest on the specially-created gravel islands. A pair of avocet succesfully bred here in 2023 and there are several species of widlfowl on view, including teal and shelduck. Over 20,000 birds visit Poole Harbour each year to feed and roost. Brownsea Island is managed in partnership with Dorset Wildlife Trust who look after the northern part of the island, including the lagoon and surrounding wetland areas.

The various hides clustered around the edge of the lagoon offer a great perch to watch all the comings and goings of the various bird life.

The lagoon behind Agent's House, Brownsea Island, Poole, Dorset — Brownsea Lagoon | © National Trust / Mike Henton

Woodland and heathland residents

Out on the heathland, the well camouflaged, nocturnal nightjar returns from Africa. Any visitors staying overnight may be lucky enough to spot them flying at dusk. On warmer days lizards can often be seen basking in the sunshine.

The woodlands and reedbeds fill with bird song in the spring, including newly arrived warblers, such as the willow warbler. This species looks very similar to a chiffchaff, but has a completely different song. Join us on one our early morning bird walks to learn more about the variety of birdlife that make Brownsea their home.

Brimstone butterflies emerge from winter hibernation on warm spring days, look out for a flash of yellow in amongst the wet woodlands and along the tracks that criss-cross the island. The word 'butterfly' is thought to originate from the yellow colour of male brimstones.

Early bird walk details

Brimstone butterfly on dandelion at Stiffkey Marshes, Norfolk — Brimstone butterfly | © National Trust Images/Rob Coleman

Red squirrels

Spotting seasonal behaviour

The red squirrel breeding season starts with mating chases in January, and a first litter of three to four babies, which are called kittens, is usually born in March. So you may be lucky enough to spot a young kit as they gain independence as the season goes on as they are weaned after 10 weeks, though some may remain in the drey until Autumn.
If a female squirrel gains sufficient food over the summer months, she will have a second litter in July/August. So if you spot a squirrel busily gathering leaves and climbing trees, it may be a new mum.
Much like our Scouting and Guiding friends on the island, a squirrel’s motto could well be, ‘be prepared’. Squirrels start stockpiling for winter early, so later in the summer and through autumn, you may catch a squirrel beginning the act of ‘scatter hoarding’. This is a process that splits the risk of losing their stash to another squirrel for example, by stashing their food in several scattered hordes. This may include seeds, nuts, tree bark, leaves, pinecones, buds, acorns, fungi, fruit, insects, and more.

Accessing the Dorset Wildlife Trust area

The Dorset Wildlife Trust manage the lagoon and wetland areas and there is a suggested donation of £2 to enter this part of the island, which includes access to hides and admission to the Villa Wildlife Centre which has an exhibition, gift shop, toilets and a feeding station for red squirrels.

Live webcams installed by the Dorset Wildlife Trust and Birds of Poole Harbour offer the chance to watch the comings and goings live. Catch up with all the action here.