Marine Wildlife

Is it a seal? Is it a porpoise? Is it a dolphin? You might spot any of these sea mammals in the estuaries of the River Blackwater and the River Crouch and around the Saltmarsh Coast

The Maldon District has 75 miles of coastline to explore, plus two river estuaries, the Blackwater and the Crouch, so it’s not surprising that you have a good chance of seeing sea mammals on your visit.

The most common creature you are likely to see is the seal, as there are two well-established seal colonies near Burnham-on-Crouch, one in the mouth of the river on the Foulness sands, and the second in the River Roach which joins the Crouch at Foulness. The seal colonies here are common seals, the smaller of the British seal varieties, weighing up to 100kg.

What can be confusing is that the seals that live in the River Roach are remarkable for their almost red colouring – caused by iron deposits in the mud – making them look a little different from other common seals. Common seal pups are born from May to July and are capable of swimming within an hour of birth, and of suckling under water. At low tide they bask on the mudbanks – and this is the best time to see them. They are quite inquisitive and may well slide off the mud and swim over to get closer to your boat!

• Group of common seals courtesy of Seal Trips Essex

You might also spot the occasional grey seal; these are larger (up to 250kg) and have a much more pronounced nose that the common seal. Grey seal pups, more commonly seen in Norfolk, are born in late autumn and winter.

If you see a marine mammal with a distinctive fin you are most likely seeing a harbour porpoise, the smallest and most common cetacean (the collective name for all whales, dolphins and porpoises) in British waters. The harbour porpoise, pictured below, has a small, round head with no obvious forehead or beak and has a dark grey back with paler grey patch on its sides and a white belly. It has a low triangular dorsal fin in the centre of its back which you can see when it swims near the surface, although it doesn’t often jump right out of the water.

• • Harbour Porpoises photographed by Nicola Hodgins for WDC Whale and Dolphin Conservation

  You might also be lucky and see the common dolphin in the coast around the Maldon District – one has even been spotted coming right up the river by Promenade Park! You can identify the dolphin as it has a more curved fin that a porpoise and also has a distinctive beak.

Discovery Seals