Hypotheses
General
hypothesis: Global warming will cause a retraction of endemic Arctic
copepod species
range and will extend the
range northward of species from lower latitudes. Despite SW transport of low salinity water, the
optimal population growth conditions will shift northward for both Arctic and NWA populations resulting
in a concomitant northward increase in NWA species and shrinkage of Arctic species
range.
H10: Boreal species in the NWA, Calanus finmarchicus and Pseudocalanus newmani and P.
moultoni will expand into Arctic
Ocean despite limitations due to the mean southwest
advective flow.
H20: Arctic species, Calanus glacialis and C. hyperboreus,
abundance will decrease in the NWA and their ranges will be contracted within the Arctic Ocean
itself. Alternatively, (H2a) abundance of these species
will increase in the NWA due to increased Arctic outflow.
H30: Calanus marshallae will expand into the Arctic and be
carried through the Canadian archipelago into the NWA
H40: The warm water NWA species, Centropages typicus and
Centropages hamatus will expand northward increasing abundance the Labrador Sea and
Canadian archipelago. The rate of expansion will be slower for Centropages hamatus which lays
bottom resting eggs.
H50: The mechanisms controlling biogeographic patterns in copepod
species can be understood
by modeling the evolution of optimal life history traits for given
environmental conditions
and climate scenarios.