Stevenston Beach Local Nature Reserve contains the last fully forming sand dune system in North Ayrshire: its sands are continually shifting and changing the dynamics of the dunes. Rare sand dune vegetation such as Babington's Orache and Isle of Man Cabbage have been recorded. There is a bountiful supply of common dune wild flowers, such as Kidney Vetch, Tufted Vetch and Bird's-foot Trefoil, which in turn support large numbers of insects. Lots of Common Blues, Small Heaths, Small Coppers, and Graylings can be found in the dunes on hot summer days. Truly outstanding, though, is the number of Six-spot Burnet moths: several hundred of these attractive black and red moths can be seen on the wing at once.
The dunes are more exposed and weather-beaten than the dunes on the Ardeer Peninsula. Consequently, the density and diversity of bee and wasp species is less pronounced than the peninsula's. However, several rare bee and wasp species have been recorded here, including Colletes floralis (Northern Mining Bee), Oxybelus uniglumis (Common Spiny Digger Wasp) and Megachile circumcincta (a species of leafcutter bee).
The neighbouring beach supports large flocks of waders. Sanderling, Dunlin and Ringed Plover in particular are present in good numbers. Hundreds of Oystercatchers can be present on the neighbouring beach park. Unusual birds that regulary occur on the beach during migration include Brent Goose, Little Stint and Golden Plover. Curlew Sandpiper and Ruff also occur on passage, but less frequently.
The beach's strandline supports a rich invertebrate fauna, which is taken advantage of in winter by small flocks of passerines such as Twite, Linnet, Pied Wagtail and, occasionally, Snow Bunting.
Overhead, Ravens can often be seen flying between the Ardeer Peninsula and the slaughterhouse in Saltcoats, where they feed on discarded animal parts.
There is also a great deal of wildlife interest out at sea, much of which can readily be observed from shore. Stevenston Point is a popular watchpoint, as it juts out into the sea. Rare migratory seabirds are regularly observed in autumn (and to a lesser extent spring) as they pass by. These include Grey Phalarope, Sabine's Gull and all four species of Skua.
Especially when the sea is calm, a wide variety of wintering wildfowl can be observed out at sea. Eider, Common Scoter and Red-throated Diver are common. A flock of Great-crested Grebe regularly winters in the bay between Stevenston and Irvine. From time to time more unusual species of grebe turn up, such as Slavonian Grebe and Red-necked Grebe. Velvet Scoter and Long-tailed Duck are seen most years.
As well as interesting seabirds, Stevenston's maritime habitat regularly plays host to a wide variety of larger creatures. Common Porpoise and Common Seals are regualrly seen, but many other, more unusual sea creatures have been encountered by patient observers, including Bottle-nosed Dolphins, Minke Whales and Basking Sharks. Again, flat, calm conditions are best when observing.