The Ribble and Alt Estuaries, Mersey Estuary and The Dee Estuary are sites of national and international importance for their wader and wildfowl populations. They have been classified as Special Protection Areas (SPA) for many waterbird species. The Mersey Narrows and North Wirral Foreshore is also an important site for birds and is currently a potential Special Protection Area.
The Wetland Bird Survey (WeBS) is a long-running survey that records the number of all waterbird species on different geographical count units (sectors) of the Ribble and Alt Estuaries SPA, the Mersey Estuary SPA, the Mersey Narrows and North Wirral Foreshore potential SPA and The Dee Estuary SPA (as well as many other sites nationally) at monthly intervals. These data can be used to assess population trends in different parts of these sites. Specific aims of this report were to:
- Utilise WeBS data to identify the abundance trends over the last 15 years in each of the WeBS count sectors within the project area for a total of 29 species and to compare these trends within their respective SPAs and pSPA, across the project area, with The Dee Estuary SPA and across the North West region as a whole.
- Identify those WeBS sectors in which substantial numbers of species are declining or increasing contrary to, or more rapidly than on the SPA or pSPA as a whole.
- Identify those sectors that support a substantial proportion of species that are declining on the SPA/pSPA as a whole.
- Where possible identify potential drivers of change in the sectors where changes in waterbird populations are observed, such as changes in food supply or suitable roosting and feeding habitats.