Application of LME Indicators: Scotian Shelf LME and the US Northeast Shelf LME 2005-2010
Transcript of Application of LME Indicators: Scotian Shelf LME and the US Northeast Shelf LME 2005-2010
GEF International Waters ConferenceSalvador, Brazil20-27 June 2005
APPLICATION OF LME INDICATORS:
SCOTIAN SHELF LME and
THE U.S. NORTHEAST SHELF LME2005-2010
10 U.S. LMEs10 U.S. LMEs
THE SCOTIAN SHELF LME
From: Frank, Petrie, Choi, and Leggett. 2005. Trophic cascades in a formerly cod-dominated ecosystem. Science 308:1621.
CHANGING CONDITIONS
From: Choi, Frank, Leggett, and Drinkwater, 2004. Transition to an alternate state in a continental shelf ecosystem. Can. J. Fish. Aquat. Sci. 61:505-510
NORTHEAST SHELF LME
An undulating oceanographic recorder (above), towed behind a ship, is used to collect ecological parameters needed to assess the state of the marine ecosystem (left).
PRODUCTIVITY INDICATORS
Northeast Shelf Meteorology
Climate Drivers of the Northeast Shelf Ecosystem
• Warm Gulf Stream waters• Cold Scotian Shelf incursions• Winter North American cold air• Warm Gulf of Mexico air• Position of westerly North American jet
air stream
from O. Hertzman, 1996
General Circulation of the Northeast Shelf Ecosystem
FISH AND FISHERIES INDICATORS
• Demersal species surveys• Pelagic species surveys• Ichthyoplankton surveys• Invertebrate surveys (clams, scallops,
shrimp, lobster, squid)• Essential fish habitat• Marine protected areas
COMMON TERMS from Our Living Oceans Report
• Recent average yield (RAY)• Current potential yield (CPY)• Long term potential yield (LTPY)• Stock level relative to LTPY• Status of resource utilization• Threatened or endangered• Potential biological removal (PBR / MMPA)
Figure 6-8. Top - Atlantic herring commercial landings and spawning stock biomass, 1967 through 1996 (thousand metric tons). Bottom - Atlantic mackerel landings and spawning stock biomass, 1963 through 1996 (thousand metric tons).
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