The environment of the fleet varies from salt waters at the Ferrybridge to fresh water at the Abbotsbury end; this allows a huge variety of wildlife to exist in a relatively localised area in fact the Fleet boasts the greatest diversity of wildlife of any lagoon in the UK making it a great educational attraction.
The Fleet is home to many wading birds every winter 10,000 Wigeon and 5,000 Brent Geese spend the winter at the lagoon.
The mudflats and shallows waters attract wading birds such as Oystercatcher, Curlew, Dunlin, Ringed Plover and Redshank. Cormorant’s fish for eels and flounders in the Fleet, and are often seen sitting in poles. Gray Herons and Little Egrets are also common.
Most conspicuous are the Brent Geese from Siberia and Wigeon from Russia. There are also important populations of Gadwall, Pochard, Red-breasted Merganser, Pintail, Shoveler, Goldeneye, Teal and Coot. In spring the fleet welcomes migrants from Africa who come to breed. Common and Little Terns can be seen diving into the water for immature fish.
Near Abbotsbury the lagoon supports the largest Mute Swan population in Britain and the only managed colony of nesting mute swans in the world, colony here can number over 600 swans with around 150 pairs a rare site as Nesting Mute Swans are usually intensely territorial, making it unusual to see this many pairs in proximity to each other.
The most common mammals to be found on the beach are rats and foxes. One animal you wouldn’t expect to find on Chesil is the hare, how ever they live and breed quite happily and can often be see running along the beach. There have even been seals recorded sitting on the beach and in the Fleet during the summer months.
There have been 300 species of flowering plants recorded on Chesil and in the Fleet, the most obvious being the Thrift which creates a spectacular carpet of pink during May giving it its local name Sea Pink. Other more rarer species include Four-leafed Allseed, Sea Pea, Yellow-horned Poppy and Sea-kale, while the principle salt marsh plants are Shrubby Seablight, Sea Purslane and Glasswort.
30 species of fish have been recorded in the Fleet including Bass, Grey Mullet, Two-spot Goby, Ballan Wrasse, Corkring Wrasse and Tompot Blenny.
Also to be found are 150 species of seaweed, 25 species of fish and 60 species of mollusks.