Wildlife of the harbour shore

The shores of Poole Harbour

One of the largest natural harbours in the world, Poole Harbour as we know it today was created when sea level rose after the last ice age.

The rivers that flow into it – the Frome and the Piddle– carry fertile sediment from inland and deposit most of it in the harbour, long before they reach the open sea. 

When the tide is out, much of this sediment is exposed; a wide expanse of mudflats, rich in nutrients and home to a wealth of algae and invertebrate life, that has become the feeding ground for tens of thousands of wetland birds. 

Mudflats and the intertidal zone – the area between the high and low water marks - are pretty inaccessible habitats. In fact, their remoteness and freedom from people is one reason why wildlife continues to thrive there.

A trip to the well located bird hides in Brands Bay (Studland) and Middlebere, however, allows you to go close but remain undetected: they are some of the best places around to see waders such as redshank, grey plovers, curlew and bar-tailed godwit, or ducks such as the wigeon, pochard and gadwall.

Gadwall are a winter highlight, along with curlew, bar-tailed godwits and pintails
A gadwall

While the frequent flooding by salt water makes the tidal mudflats inhospitable to most plant life, a number of specialist plants thrive here. 

Cordgrass, or Spartina, is the dominant plant in these saltmarsh communities, but look closer and you will find a wide range of often rare plants such as the beautiful sea lavender, glassworts (including the edible samphire) and sea rushes. 

As with all specialist habitats the saltmarsh is home to specialist creatures too; including the lesser marsh grasshopper and several nationally rare moths and beetles.

Redshank flock here to breed in spring
A redshank feeding

We don’t actively manage saltmarsh; it is naturally occurring and one of our few habitats that doesn’t rely on traditional management practices. 

However, it is also one of those that is most at risk. Recent evidence shows that disturbance from both land (principally in the form of dogs) and sea (in the form of kayaks) is impacting on the success of overwintering and breeding birds.

If you're very lucky, you may even spot a visiting osprey in summer
An osprey in flight

Longer-term, saltmarsh is one of the habitats that is most at risk from climate change, sea level rise and increased storm activity: our approach here is to allow the saltmarsh to ‘migrate’ slowly inland as the sea rises, by making sure that there are no hard barriers that prevent this from happening. 

You can find out more about our approach to looking after the important habitats along the coast in our Shifting Shores policy - see below.