I haven't birded Edmonds as much as many, however I've found in other areas
that Ancient Murrelets and other alcids are much easier to find in between
tides. Often at places here in the south Sound you can bird at high tide and
see very few saltwater species. An hour or more later, you will begin to see
alcids flying by or diving in flocks around the rip. It does seem to me that
Brian is correct in saying it depends on the food source, but I think there
must be a correlation between the two in normal circumstances. It's probably
variable by location; some places being more tide dependent than others.

Good birding,
Charlie Wright
Birdking88 at aol.com
Sumner, WA