Site feature providing more detailed description, photos and other information for the butterfly observer

Photo 1 - View Across Pennington Lagoon from the Sea Wall Footpath


Hampshire & IoW Wildlife Trust Nature Reserve of international importance

Site of Special Scientific Interest

Currently the only reliable site in Hampshire for the Wall butterfly. Green Hairstreak also present

Plenty to interest the visitor in addition to butterflies and wildlife, including nearby Hurst Castle/Lighthouse



The Lymington-Keyhaven Coastal Nature Reserve is internationally recognised for its wildlife. Whilst best known for its populations of wading birds and specialist flora, it also has plenty to interest the butterfly observer. The area has its own special sense of place with salt marshes, shallow lagoons, mudflats and views of two lighthouses - one across the Solent at the Needles on Isle of Wight, the other nearer to hand at Hurst Castle, which can be reached on foot from Keyhaven or by ferry (summer only). The area is also historically significant having been used since Roman times (until the mid-1800s) for the extraction of salt from sea water using "salterns". As for butterflies, the reserve seems now to be the only location in Hampshire where one can see, with reasonable reliability, the Wall butterfly, now scarce in S England. Green Hairstreak are also reported from the reserve and common butterfly species.

One can approach the reserve from either end (Lymington or Keyhaven) or from the north, via Pennington Lane. I am more familiar with the approach from Keyhaven which I will use as the reference for this feature. 
Park in the car park in Keyhaven, arrowed on this map and leave by the rear pedestrian exit. Then head east across the bridge over the little estuary at the mouth of the Avon water. At the end of the bridge turn right through a gate to follow the shoreline.You may see common species along this stretch but butterfly interest does not really start until you reach the lagoons, the first of which is the Keyhaven Lagoon in about ½ mile, where there is an informative visitor display board about the reserve. At extreme high tides, the water can lap over one short section of the shoreline path on the way to the lagoons, but you would be extremely unlucky to find it impassable (wear sturdy waterproof footwear!).

Once at the visitor board you can take the high level path along the sea-wall or the more sheltered, low level path beside the lagoons, which has been the more productive in my experience. The route can be followed for about two miles past several lagoons - Keyhaven, Fishtail, Butts, Pennington and Oxey respectively. About half way along there is a small jetty between the Butts and Pennington lagoons as a reference point. The margins of these lagoons along the low level path and the sea-wall path is a favourite haunt of Wall butterflies - mid May and early August are normally best times to visit for this species, however there is usually a small 3rd generation in late September/early October.

Other interesting detours can be made inland from the lagoons. One such triangular detour is around the "old tip" (photo 2 below). In this case take the track inland from the jetty mentioned above towards the Pennington Lane car park (map). This track in particular is another  favourite haunt of the Wall. Return to the seashore by turning sharp left at the car park, to follow another the track beside a water-filled drainage ditch (track not marked on OS Landranger).

Photo 2 - Site Of The Old Tip - The Tracks Bordering It Are Favoured Haunts Of The Wall Butterfly

For other butterfly species these inland areas are also quite productive. Common species to look out for include Meadow Brown, Gatekeeper, Small Heath, Painted Lady, Red Admiral, Peacock, Common Blue, Small Copper  and Holly Blue. Green Hairstreak are also reported from the reserve although I have not been successful myself.