An estuary retreat

The Dunlin departure was apparent from just before mid-month. In the eastern half of the estuary, the roost numbers dropped and for the remaining birds very few now followed with the tide- it was almost as if the falling pressure of numbers allowed the smaller flocks to feed more leisurely.

This effect was the same in the western half, but not as apparent to the casual observer, as numbers loitering on the flats close to Rainham might not, at first, have seemed to have dropped. But close to this prime area, Dunlin using the flats east of Horrid Hill were greatly reduced, and fewer flocks could now be found out mid-channel. Birds that remained were not moving far. Correlations/causations- certainly the second half of the period was notable for some particularly slack neap tides, helping stop the Rainham flats from draining quickly, but it was also noticeable the birds were choosing not to roost so further away, largely giving up on Bishop and using the nearer Friar's saltings instead. Reasons can only be guessed at; e.g., could the antics of the gulls re-establishing on Bishop now be having an effect? Why risk moving a tad closer to the two young Peregrines often seen loafing on Nor? The roosting Dunlin were certainly being put to flight more often, heading south-west to Motney saltings, which they had ignored for the greater part of the winter.

Questions, questions. Including, of course, 'so how do the numbers compare?'

As before, these numbers for the south Medway are merely a representation, impossible to simply 'add up'. If I had to offer a considered opinion, I'd estimate a drop of about 50-60% between periods. Now very interested to see what changes the third period brings.