In addition to its rivers, Berkshire has a wide range of ponds and lakes on which grebes may be found. Many of our water bodies are gravel pits, of varying ages and stages of vegetation development. Whilst Great Crested Grebe population seems fairly stable, Little Grebes have been declining rapidly. This survey seeks to help us understand why.
Great Crested Grebe Although quite common on Berkshire waters, Great Crested Grebes were classed as Vulnerable in a recent analysis (Stanbury et al, 2017. British Birds 110, 502-517). The total breeding population in Great Britain is around 9,000 birds, of which Berkshire holds 3-5%. The Atlas (The Birds of Berkshire, 2013) shows tetrad occupancy to have been stable between 1989 and 2009, with 220-250 pairs recorded in the more recent Atlas surveys. In the 1975 national survey, 40 water bodies in Berkshire were reported occupied and 302-340 birds recorded (The Birds of Berkshire, 1996).
Little Grebe The tetrad occupancy of Little Grebes in Berkshire almost halved between the 1989 atlas and 2011, when the population was estimated to be about 50 pairs. Since then, the numbers of records received has been falling, reflecting a national downward trend. The reasons for its decline are unclear.
The objectives of the survey are:
- To monitor as many water bodies as possible for both Little Grebe and Great Crested Grebe.
- To characterise the habitat of occupied and unoccupied water bodies.
Method: Water bodies should be visited from April to mid-June and, if grebes are found, again from mid-June to August. The site description should be completed after the first visit, whether or not grebes are present. In 2018 and 2019, some 50 or so of around 200 water bodies were surveyed. A list of sites that have not yet been surveyed (January 2020) can be seen here. Please select some sites and complete the online survey form for each visit.
If you are unable to complete the form online, hard copy survey forms can be obtained from and returned to: BOC Grebe survey, 63 Hamilton Road, Reading, RG1 5RA.