Regarding zooplankton

[James W. Porter]

Dear Dr. Mackenzie and Coral list-servers,
    From our studies on coral feeding, I suspect that food-shortage issues
pertaining to reef zooplankton will come not only from pelagic zooplankton
that float over reefs, but more likely from demersal (bottom dwelling)
zooplankton that live on coral reefs.  We showed in our paper (Porter, J.W.
and K.G. Porter. 1977. Quantitative sampling of demersal plankton migrating
from different coral reef substrates. Limnol. Oceanogr. 22:553-556.) that
physically damaged or degraded coral reef habitats produce almost an order
of magnitude less demersal zooplankton per hour than topographically complex
and healthy reefs.  For reef organisms dependent on this food supply, reef
degradation has a seriously deleterious affect on both food quantity and
food quality.  We do not know the relative importance of pelagic versus
demersal plankton, but if I were to venture a working hypothesis, I would
say that more than 75% of both the carbon and the calories that we measured
in the guts of several reef-building coral species came from demersal
plankton and not from pelagic plankton.
    Good luck with further research on your interesting and novel
perspective.
    Jim Porter