Physical control of the distributions of a key Arctic copepod in the Northeast Chukchi Sea
Authored by Yu Zhang, Changsheng Chen, Zhixuan Feng, Carin J Ashjian, Stephen M Elliott, Benjamin Jones
Date Published: 2017
DOI: 10.1016/j.dsr2.2016.10.001
Sponsors:
United States National Science Foundation (NSF)
Platforms:
No platforms listed
Model Documentation:
Other Narrative
Model Code URLs:
Model code not found
Abstract
The Chukchi Sea is a highly advective regime dominated by a
barotropically driven northward flow modulated by wind driven currents
that reach the bottom boundary layer of this shallow environment. A
general northward gradient of decreasing temperature and food
concentration leads to geographically divergent copepod growth and
development rates between north and south. The physics of this system
establish the biological connection potential between specific regions.
The copepod Calanus glacialis is a key grazer, predator, and food source
in Arctic shelf seas. Its summer distribution and abundance have direct
effects on much of the food web, from phytoplankton to migrating bowhead
whales. In August 2012 and 2013, C. glacialis distributions were
quantified over Hanna Shoal in the northeast Chukchi Sea. Here an
individual-based model with Lagrangian tracking and copepod life stage
development capabilities is used to advect and develop these
distributions forward and backward in time to determine the source
(production locations) and sink (potential overwintering locations)
regions of the transient Hanna Shoal C. glacialis population. Hanna
Shoal supplies diapause competent C. glacialis to both the Beaufort
Slope and the Chukchi Cap, mainly receives juveniles from the broad
slope between Hanna Shoal and Herald Valley and receives second year
adults from as far south as the Anadyr Gulf and as near as the broad
slope between Hanna Shoal and Herald Valley. The 2013 sink region was
shifted west relative to the 2012 region and the 2013 adult source
region was shifted north relative to the 2012 adult source region. These
connection potentials were not sensitive to precise times and locations
of release, but were quite sensitive to depth of release. These patterns
demonstrate how interannual differences in the physical conditions well
south of Hanna Shoal play a critical role in determining the abundance
and distribution of a key food source over Hanna Shoal and in the
southern Beaufort Sea.
Tags
Water
Ecosystem
zooplankton
Variability
Transport
Ocean
Shelf
Calanus-glacialis
Advection
Fall
Distribution
Arctic ocean
Summer
Mesozooplankton
Calanus
Chukchi
sea
Hanna shoal