Nearshore Ecology of Atlantic Salmon in the Gulf of Maine Region. Workshop 2: Bays and the Gulf of Maine

Transcription

1 Nearshore Ecology of Atlantic Salmon in the Gulf of Maine Region Workshop 2: Bays and the Gulf of Maine

2 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

3 Common Marine Environment US Stocks Highly Migratory Inner Bay of Fundy Stocks- Limited Migration

4 The Problem: Declining Abundance North Atlantic Wide 4,, 3,, Total Europe North America number 2,, 1,, year Data Source: ICES 26

5 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

6 Legault (24/25) PVA illustrates freshwater, marine, and stocking Returns to DPS Stocking Base Juvenile S +.8 Marine S +.4 Juv S+.4&Mar S Year

7 Poor Marine Survival: an Atlantic-wide Issue USA/Scotia Fundy - hatchery Gulf Region/Quebec - wild standard return rates SW 2SW SW 2SW Northern Europe - wild 3 Southern Europe - wild survival Z Scores SW 2SW SW 2SW Data Source: ICES 26

8 Observation 1: Scale Issue Lower Abundance Remnant of 4H s? 25, 2, Canada USA 2SW returns 15, 1, 5, 8, 6, 4, 2, year North American Returns (2SW only) Data Source: ICES 26

9 Observation 2:Phase/Regime Shift Change in Ocean Productivity 8, PFA abundance 6, 4, 2, , 4, 6, 8, 1, 12, North American lagged spawners Data Source: ICES 26

10 A Salmon s Ocean Life: A big black box spawn hatch parr smolt postsmolt adult spawning

11 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

12 Progress has been made: Number Crunching 2,5 2, Pre1995 SmoltAdj Estuary Adj Abundance 1,5 1, Post Smolt Week spawn hatch parr smolt postsmolt adult spawning

13 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

14 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

15 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

16 12 GoM BoF Region Time and Space Number of Smolts Caught 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

17 Small Fish Big Water - Surface Ecosystem Atl. Mackerel Lumpfish Atl. herring Blueback herring Alewife Other

18 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

19 Telemetry Investigations: Migration/Survival dynamics Narraguagus river kilometer depth (m) Smolts Per Hundred Survival Curve time Penobscot smolt with depth tag 1 Release Riv Est IB MB OB Ecological Zones

20 Salmon s Ocean Life: Many smaller black and grey boxes spawn hatch parr smolt postsmolt adult spawning

21 Our Task: Ho and Rx for Sustainable Populations freshwater survival 2% 15% 1% 5% % Current Rates Year Historical US freshwater survival ( %) % 1% 2% 3% 4% 5% 6% 7% 8% 9% 1% marine survival Returns to DPS