Gibraltar Point NNR is an integral component of the Wash system of intertidal mudflats and saltmarshes.  The whole system comprising the most important UK site for non-breeding waterfowl, with numbers peaking at over 300,000 waders and wildfowl.  Thirteen species occur in the Wash in internationally important numbers (ie over 1% of the population) as follows; dark-  bellied brent goose Branta bernicula, pink-footed goose Anser brachyrhynchus, shelduck Tadorna tadorna, oystercatcher Haematopus ostralegus, grey plover Pluvialis squatarola, lapwing Vanellus vanellus, knot Calidris canutus, dunlin Calidris alpina, bar-tailed godwit Limosa lapponica, black-tailed godwit Limosa limosa, curlew Numenius arquata, redshank Tringa totanus, and turnstone Arenaria interpres.  Some of these species migrate to breeding grounds in Siberia, Greenland or Arctic Canada.

The estuarine mudflats and saltmarshes provide rich feeding grounds for the key species, whilst the shingle ridges provide roost sites at high tide.

Gibraltar Point hosts one of the principle wader roosts in the Wash and receives independent recognition as a Ramsar site and SPA for use by Internationally important populations of dark- bellied brent goose, grey plover, bar-tailed godwit, knot and sanderling on passage and wintering. Other species of waterfowl occur in nationally important numbers and complement this assemblage.  The key period is from August to April for most species, although autumn build-up may involve high numbers from mid-July and the sanderling spring peak passage is often in late May or even early June.

During passage periods, over 30,000 waders may be present, sometimes double this at peak passage periods in spring and autumn on the highest spring tides (figures are appended).

Where feeding and roosting habitats are in favourable condition, disturbance free and support at least 5 internationally important populations of waders/wildfowl.