During last week's half-term I spent a few days with friends in Wivenhoe, Essex. Between the rain and snow showers we got out to the coast near Bradwell, infamous for the nuclear power station (currently disused). However nearby is the Bradwell Cockle Spit nature reserve characterised by its shell banks and established to protect shore nesting birds such as the Little Tern (Sterna albifrons).
On a cold February afternoon we were treated to the spectacle of wintering waders amassing during the high tide and performing their frequent sky shows. Triggered by passing raptors or perhaps just for practice, up they would go with synchronised twisting and flashing; dark then light they whirled over the waves like a mobile mexican wave. The most spectacular display however was as they flew close to the water surface like giant glitter catching the winter sun. These flocks were mainly Knot (Calidris canutus), mixed with Dunlin (Calidris alpina), Grey Plover (Pluvialis squatarola) and Ringed Plover (Charadrius hiaticula). The theory is that this community behaviour confuses predators such as peregrine, that patrol shorelines hunting such prey. Whilst we were there we witnessed a kestrel causing such a reaction.
On the shore itself we found a dead wader (see picture) which with the slightly downturned and longish beak was identified as a Dunlin. This species can be easily confused with less common species due to great variability in size and plumage colouration. It was clearly a fairly recent death, but the cause not. Interestingly further up the beach we found a dead fox and rat. Quite a death toll for one walk.