The week ended with a leisurely stroll around Fen Drayton lakes, a series of gravel pits adjacent to the River Ouse. This is a good site for wintering waterbirds, notably including Smew and Bittern, and now also supports a couple of ‘booming’ Bitterns and breeding Marsh Harriers. Fen Drayton is one of the very few remaining sites for Grass-poly, now classified as ‘endangered’ in the UK. The usual site held just one plant that I could see, but as I wandered around, many flowering plants were visible in a new location. This is a plant that requires disturbed ground with winter flooding and a spring draw-down. A programme of spring rotovation of plots should see it survive here.
Ringed Plover (on Scottish machair), Grass-poly and a view across Moore Lake, Fen Drayton.
The site also supports a selection of typical gravel pit waders; LRPs, Ringed Plovers and Oystercatcher, as well as Lapwing and Redshank. It was good to see a pair of Ringed Plovers with chicks. After their surge into inland sites in the late 70s and 80s, this seems to be a bird that is withering away as a breeding species in the south-east. The inland birds are now much scarcer and those on the coast struggle against disturbance and sea level rise. The latest national survey reported a 37% decline, with the greatest decreases in inland areas.
The key for both the poly and the plover at Fen Drayton is the retention of some typical early succession gravel pit habitat. Yet natural succession is usually rampant at these sites, and before long, all you have is a tree-lined pool of dullness, unless some drastic management is undertaken. Fen Drayton’s greatest asset is its location in an active floodplain. Floods from the Ouse can put the whole site under water but this makes the habitats more dynamic. Combining this with the actions of large herbivores and some periodic ‘knocking about’ with big machines (to create habitat at the right level in the flood regime) should see the value of the site being maintained.
Apart from the Ringed Plover, it was fairly quiet on the bird front. Lots of moulting Tufted Duck and Pochard, a Hobby or two, Dunlin and Redshank on muddy islands, and a family of Water Rails.