Nearshore Ecology of Atlantic Salmon in the Gulf of Maine Region Workshop 2: Bays and the Gulf of Maine
Atlantic Salmon Life Cycle adults postsmolts 1SW or 2SW Jun 4 Jun 5 Jun 3 Nov HATCHERY Inputs eggs Jan 1 May 3 smolt Inputs Parr Fry Apr 3 Jun 1 alevin
Common Marine Environment US Stocks Highly Migratory Inner Bay of Fundy Stocks- Limited Migration
The Problem: Declining Abundance North Atlantic Wide 4,, 3,, Total Europe North America number 2,, 1,, 1971 1976 1981 1986 1991 1996 21 year Data Source: ICES 26
Core Reviews/Resources DFO (21) 12 top Ho 1 estuary marine 1 is fw-marine interaction 2 freshwater NSF URGENT (24) Dams Early Marine Survival Hatcheries
Legault (24/25) PVA illustrates freshwater, marine, and stocking Returns to DPS 4 3 2 1 Stocking Base Juvenile S +.8 Marine S +.4 Juv S+.4&Mar S+.2 22 221 24 Year
Poor Marine Survival: an Atlantic-wide Issue USA/Scotia Fundy - hatchery Gulf Region/Quebec - wild standard return rates.3.2.1 1SW 2SW.3.2.1 1SW 2SW 197 198 199 2 197 198 199 2 3 Northern Europe - wild 3 Southern Europe - wild survival Z Scores 2 1-1 1SW 2SW 2 1-1 1SW 2SW -2-2 197 198 199 2 197 198 199 2 Data Source: ICES 26
Observation 1: Scale Issue Lower Abundance Remnant of 4H s? 25, 2, Canada USA 2SW returns 15, 1, 5, 8, 6, 4, 2, 197 1975 198 1985 199 1995 2 25 year North American Returns (2SW only) Data Source: ICES 26
Observation 2:Phase/Regime Shift Change in Ocean Productivity 8, 1978-1988 PFA abundance 6, 4, 2, 1989 199-24 2, 4, 6, 8, 1, 12, North American lagged spawners Data Source: ICES 26
A Salmon s Ocean Life: A big black box spawn hatch parr smolt postsmolt adult spawning
NOAA NEC Programs- Progress has been made Pre-1995 Large parr estimate Assumed overwinter survival Adult returns Post -2 Large parr estimate Overwinter survival Smolt estimate Estuarine mortality Nearshore mortality Harvest Adult returns Large unknowns still remain spawn hatch parr smolt postsmolt adult spawning
Progress has been made: Number Crunching 2,5 2, Pre1995 SmoltAdj Estuary Adj Abundance 1,5 1, 5 15 35 55 75 95 115 135 Post Smolt Week spawn hatch parr smolt postsmolt adult spawning
More Progress Needed: Salmon Ecosystems Research and Management 29 and beyond Large parr estimate Overwinter survival Smolt estimate Estuarine mortality Nearshore mortality Harvest Adult returns spawn hatch parr smolt postsmolt adult spawning
Workshop Purpose: Ecology of Gulf of Maine Atlantic Salmon in Nearshore Marine Ecosystems Workshops- bring together marine scientists of multiple disciplines to discuss and develop: testable hypotheses to advance our understanding of current low marine survival of Atlantic salmon and management prescriptions to increase marine survival Multi-disciplinary - awareness, communication, collaboration, and action Outcomes - Refine NOAA program around agency strengths (focus current resources) Develop new programs interdisciplinary programs (initiatives for expanded research and management actions) Products: Sea Grant NOAA Lab Reference Document Synthesis in Fisheries
Additional Concepts Time and Space Smolt- Post smolt: nearshore May-July, heavy losses first months Returning Adults: nearshore May-October Small fish in big ocean Relatively Small Size- upon sea-entry Numbers Overall needle in haystack However not many other surface oriented fish But likely not a driver or keystone species
12 GoM BoF Region Time and Space Number of Smolts Caught 1 8 6 4 2 26-Apr 3-May 1-May 17-May 24-May 31-May 7-Jun 14-Jun Date May Telem May- Jun Telem MayJun-Jul Telem Telem June PST June Telem Late June Telem May-Jun PST June PST
Small Fish Big Water - Surface Ecosystem Atl. Mackerel Lumpfish Atl. herring Blueback herring Alewife Other
Additional Concepts Surface Orientation Smolt- post smolt: top 5 m of water column, some sounding occurs, not well understood Early losses high r-selected species survival curve telemetry analyses
Telemetry Investigations: Migration/Survival dynamics 1 1 9 Narraguagus 2-4 -2 river kilometer 2 3 4 5 depth (m) Smolts Per Hundred 8 7 6 5 4 3 2 Survival Curve time Penobscot smolt with depth tag 1 Release Riv Est IB MB OB Ecological Zones
Salmon s Ocean Life: Many smaller black and grey boxes spawn hatch parr smolt postsmolt adult spawning
Our Task: Ho and Rx for Sustainable Populations freshwater survival 2% 15% 1% 5% % Current Rates 4 3 2 1 22 221 24 Year Historical US freshwater survival (.13-6.9%) % 1% 2% 3% 4% 5% 6% 7% 8% 9% 1% marine survival Returns to DPS