Diet of Worms*

Fishguard's close neighbour (or 'twin town'') Goodwick, lies across a marshy valley (left in this picture) running down to the sea, on the right. Today the road verge was occupied by a group of oystercatchers that had abandoned the beach in favour of the grass. They were feeding on earth worms instead of mussels and cockles.

I hadn't realised that oystercatchers do this routinely when shellfish are in short supply. Like other wading birds they have sensory nerve endings at the end of their beaks that help in the detection of their prey. On the grass they walk forward in a group stabbing the ground in front and to both sides of them - but  do they do this randomly or are they seeing/sensing the presence of worms? A study set out to find the answer, replicating the birds' strategy by using forceps to try to catch worms in the ground. "The capture success rate of this method by which 300 forceps probes resulted in 3 earthworms compared with the success rate of Oystercatchers feeding in the same field one hour later, when 504 Oystercatcher pecks resulted in the capture of 41 food items, mainly earthworms" led the researchers to conclude that the birds were relying on visual or other clues not simply chance.

(What intrigues me is the reaction of the oystercatchers and maybe human onlookers to the antics of a bunch of ornithologists crawling about jabbing forceps in the ground.)

Further along, a curlew and jackdaw were having a spat, probably over worms too.

* 1521