Spring 2010 Update: Summary of Conditions of the Northeast Shelf Ecosystem
Sea surface temperature (SST) in the Northeast Shelf Large Marine Ecosystem during the second half of 2009 alternated between moderately warm and cool conditions.
There were exceptional spring and fall phytoplankton blooms on the Northeast Shelf. As a result, 2009 has the highest chlorophyll a concentrations recorded in the satellite data time series. This is a clear indication that productivity of the ecosystem is at a very high level.
Zooplankton biomass levels were average or above during most of the year.
Analyses of thermal conditions from multiple data sources indicate that the ecosystem is warming and affecting the distribution of species and biological communities. This warming trend is not uniform across the entire system, resulting in a constriction of thermal habitats on the shelf.
The ecosystem has undergone a freshening trend caused by changes in source waters, which has affected community patterns in the lower trophic levels.
The trophic level of fish landed has declined precipitously over the past three decades, reflecting changes in the biological community and metrics related to diversity and stability.
There has been a shift in fish condition, which will most likely impact individual species seasonal reproductive capacity and thus recruitment.