Are the sand-mason worms harvested?

Mediterranean Gulls - only a maximum two birds have been seen over the last three days.
Personal thought on this (MD) - the peak counts of birds feeding on the sand-mason worms on beach near wooden jetty (57 and 60+) were both within 3 days of the last two full moons. This suggests that the sand-mason worm activity that makes them easy picking, is linked to the lunar calendar. This is presumably part of their breeding cycle.
There was not a single gull on the feeding beach today, not even the Black-headed gulls who have been present before the Meds arrived. This suggests that all worm "activity" has stopped, meaning the last full moon (the Harvest moon) was the last feeding opportunity. This implies that the beach is now empty of gulls, not because the Meds have gone, but that the Meds have gone because the beach is empty (of available worms).
This theory will be checked next year, but might be interesting as the Harvest moon is not till 1/10/20!

Middleton Nature Reserve - early evening
Kingfisher - one flying around "no swimming" pond then main pond.
Gadwall 22
Mallard 9
Teal 1
Tufted 1
Little grebe 2 (1 sp)
Pinkfooted goose 33 south

Still good numbers of dragonflies around. This weekend might be the last good viewing opportunity.