THE EFFECT OF THE CIRCULATION OF WATER ON THE DISTRIBUTION OF THE CALANOID COMMUNITY IN THE GULF OF MAINE

¹ From the Biological Laboratories, Harvard University, and the Woods Hole Oceanographic Institution, Woods Hole, Mass.

1. The seasonal and geographical fluctuations of the abundance of the calanoid community of the Gulf of Maine are described.

2. The shift in the center of abundance is closely correlated with the superficial circulation, deduced from hydrographic observations and the drift of an invading population of Limacina.

3. The principal factor influencing the distribution of population density is the inflow of relatively barren water from the Nova Scotian coast in winter.

4. The Gulf appears to be an area from which the calanoid community spreads to other waters, but which receives relatively small recruitments from without its borders.

5. A breeding stock is maintained by the establishment of a recurrent eddy in the late spring.

6. Estimates of annual productivity and seasonal mortality are given.

7. The distribution of petrels and of the mackerel fishery appears to be correlated with the distribution of zoöplankton.