Wildlife watching on Brownsea Island

A juvenile white-tailed sea eagle in flight with talons down and blue sky in the background. — Juvenile white-tailed sea eagle in flight, Brownsea Island, Dorset. | © National Trust Images/ Rob Coleman

There is plenty of wildlife to see all year round on the island and things change with the seasons. Take a walk through the woodland or down to the lagoon, and don’t forget your binoculars.

Brownsea Island is now open for the season.

The island opens to the public on Saturday 14 March 2026.

Spring wildife

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

The Lookout wildlife observatory is a great place to enjoy birdwatching in any weather, offering wide panoramic views across the lagoon. From here you can spot common and Sandwich terns nesting on the gravel islands, along with waders such as redshank and oystercatcher feeding in the rich mud.

Ospreys, reintroduced in 2017, are now a regular sight over Poole Harbour. A pair have successfully bred nearby, this was the first time in more than 200 years, they can often be seen fishing in the harbour, their distinctive M‑shaped silhouette making them easy to recognise.

You may also spot the impressive white‑tailed eagle, whose huge two‑metre wingspan has earned it the nickname ‘flying barn door’. These magnificent birds have recently returned to the south coast following a reintroduction programme on the Isle of Wight.

Brownsea Island is cared for in partnership with Dorset Wildlife Trust, who manage the northern end of the island including the lagoon and wetlands. Several hides along the lagoon edge offer excellent vantage points, and a Dorset Wildlife Trust volunteer is often on hand in the first hide with a telescope linked to a screen, giving visitors close‑up views of the birdlife.

Join us on a Wild Wetland Bird Walk, led by an expert Dorset Wildlife Trust Ranger and explore one of the best birdwatching sites in the UK.

Book on a birdwatching walk here

Woodland and heathland residents

Out on the heathland, the well camouflaged, nocturnal nightjar returns from Africa to breed. Any visitors staying overnight may be lucky enough to spot them flying at dusk, listen out for their churring call and white wing markings. On warmer days common and sand lizards can often be seen basking in the sunshine and look out for green tiger beetles sprinting across the ground hunting their prey.

In the spring the woodlands and reedbeds come alive with the sound of bird song from territorial resident birds and newly arrived migrants, such as willow, reed and sedge warblers. Some of these birds look alike, some sound alike join us on one our regular bird walks to learn how to distinguish them and to find out 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.

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

Please do not feed the squirrels

Feeding the red squirrels from your hand encourages them to become tame and puts them at greater risk from disease and predators. Diseases including leprosy and staphylococcus aureus (and the related fatal exudative dermatitis) are transmissible between humans and squirrels. They are wild animals and should be treated as such. Excessive feeding attracts pests such as rats which are a threat to young squirrels and other wildlife. Pests are a vector for diseases affecting both humans and squirrels. There is an abundant natural food source on the island. You can still get great photos of the red squirrels without putting food down. Here's a few tips from us: Keep as still and as a quiet as possible. Have your camera out and ready to shoot. Keep a low profile. Be patient.

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, they are 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.

A close up of a red squirrel on a branch on the floor of woodland on Brownsea Island, Dorset — A red squirrel exploring the woodland floor at Brownsea Island, Dorset | © National Trust Images/James Dobson

An endangered species

Red squirrels are an endangered species in the UK due to the loss of their woodland habitat and the introduction of the American grey squirrel.

While both species of squirrel have a similar role in the ecosystem in that they are small woodland mammals that spread the seeds of trees, red squirrels are a particularly important asset in the regeneration of pine woodlands.

Reds are specially adapted to feed on the seeds in pine cones and greys tend to favour broadleaf woodland where many other animals can do the job of spreading the seeds, such as birds.

If red squirrels became extinct in the UK, it would not only have a negative impact on our pine woodland regeneration but we would also lose one of our most iconic native mammals.

When to see red squirrels on Brownsea

Red squirrels are most active in spring and autumn, so a visit during those seasons is the most likely to be rewarded with sightings.

They're usually spotted during the quieter times of the day, so a good time to spot them is when we first open or later in the afternoon before we close.

You could also stay overnight on the campsite and go red squirrel spotting when it’s quieter.

Try your luck on the Woodland Walk and don't forget to look up, down and all around.

Where to see them

Red squirrels are most often found in the coniferous woodland areas, feasting on nuts and seeds, or you may find pine cones that have been nibbled, leaving what looks like a nibbled corn on the cob.

Squirrels have been spotted on the woodland walk, near the Church, either posing for photographers or leaping between the oaks. Another good place to try is by the feeders up by the Villa on the Dorset Wildlife Trust managed area.

Accessing the Dorset Wildlife Trust area

The Dorset Wildlife Trust manage the lagoon and wetland areas with access to several hides and admission to the Wildlife and Wetland Centre.

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.