Input of Calanus finmarchicus into the Gulf of Maine
through the Northeast Channel
of Maine during winter
C. Ashjian,
E. Durbin, and
C. Flagg
The Northeast Channel is a potential route for input of populations of
Calanus finmarchicus into the Gulf of Maine, either from upper
water column
populations advected off of Browns Bank to the north or from populations
resident at depth in the Slope Water. Broadscale surveys of the vertical
distributions of plankton populations, accompanying hydrography, and
water
column velocities have been conducted on Georges Bank at monthly
intervals
during the winter and spring of 1995-1999 as part of the US GLOBEC
Georges Bank
program. Data from 13 cruises were examined to determine seasonal
changes
in the abundance of Calanus in the Slope Water and the direction
and magnitude of transport of Calanus through the NE Channel
during these
months. Calanus abundances in Slope Water were greatest during
the late spring-early summer. Preliminary calculations show that
Calanus usually are input into the Gulf of Maine along the eastern side of
the NE Channel,
but that outflow occurrs along the western side and that the flux of
Calanus into the Gulf of Maine through the NE Channel is variable.