Ramifications of persistent low marine survival to Atlantic salmon management in the United States

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1 Ramifications of persistent low marine survival to Atlantic salmon management in the United States Rory Saunders and Mary Colligan October 19, 2011

2 Salmon Summit Objectives to consider the management implications of recent advances in understanding of the salmon s marine life; Lessons learned from the southwestern edge of the range Interplay between dams and marine survival is critical Developing recovery criteria has greatly enhanced focus salmon programs in Maine You don t know what you got til it s gone 2

3 Map by Tara Trinko 3

4 Gulf of Maine Endangered Current Status of Atlantic salmon in the US Central New England Native stocks extinct Restoration ongoing with GOM stock Long Island Sound Native stocks extinct Restoration ongoing with GOM stock 4

5 Atlantic salmon declines Historic Dams Over-fishing Pollution Contemporary Dams Marine survival Death by 1000 cuts Water quality Water quantity Exotic species Aquaculture Many others 5

6 Accessible Habitat and Commercial Catch 100% 250,000 Accessible proportion of Penobscot watershed 80% 60% 40% 20% 0% Year Courtesy of Chris Holbrook and Ed Baum 200, , ,000 50,000 Commercial Catch (pounds) 6

7 Courtesy John Kocik and US Atlantic Salmon Assessment Committee Total Returns 6,000 5,000 4,000 3,000 2,000 LIS CNE OBF GoM 2010 Returns: 1,650 Fundy St. Croix, Aroostook % GoM Dennys to Androscoggin % CNE Saco to Merrimack % LIS Connecticut and Pawcatuck---- 3% Ranked 11 th in 44 year time series 1, Return Year 7

8 Protections of the US Endangered Species Act Listed as Endangered in 2009 Dams and Marine Survival Take is prohibited Restoration activities encouraged Critical Habitat designation Recovery Criteria development How much is enough? Protections of the ESA are no longer warranted What should recovery look like? See McElhany et al. (2000) Viable Salmonid Populations Abundance (risks inherent to small populations) Distribution (local but potentially catastrophic risks) Productivity (replacement rate exclusive of hatchery influence) Diversity (genetic risks) 8

9 Abundance Recovery Criteria ~2,000 wild spawners per SHRU 50/500 rule (Franklin 1980) PVA modeling coupled with marine survival estimates Best professional judgment Distribution 3 Salmon Habitat Recovery Units 30,000 fully accessible (suitable) habitat units in each SHRU 1 habitat unit = 100m 2 9

10 Not all habitat units are created equal Habitat suitability Temperature Biological communities Water Quality Substrate and cover Penobsco t Bay SHRU 10

11 High Quality Fully Accessible Salmon Habitat Units by SHRU 200, , ,000 Inaccessible Limited Access Full Access 50,000 0 Merrymeeting Bay Penobscot Downeast Courtesy Tara Trinko Lake 11

12 Recovery Criteria Productivity Replacement rate > 1.0 for 2 generations (10 years) Diversity No specific goals Focus is on preservation of current diversity levels 12

13 Conclusions Interplay between dams (i.e., lack of connectivity) and marine survival critically important Dams have reduced salmon abundance directly and the life history options available Diminished capacity to sustain low marine survival regime Diminished capacity to respond to environmental variability Can this capacity be recovered? U.S. Endangered Species Act compels the attempt 2009 Endangered Listing Highlighted Dams and Marine Survival Dams prioritization, removals, performance standards at hydro dams Marine survival - Telemetry, trawling, ICES/NASCO, Estuary survey, SALSEA WG, SALSEA North America 13

14 Conclusions Could we have sustained the low marine survival observed since 1991 if we had 6,000 adults and 90,000 accessible habitat units? We think so Retrospective recovery criteria development has focused the program greatly So if the problems are dams and marine survival, what can we do about it? Co-restoration for the co-evolved suite of diadromous fish 14

15 Co-restoration for co-evolved species Habitat conditioning Marine-derived nutrients Prey buffer Diversified prey base Artwork by Dr. Mark McCullough 15

16 Acknowledgements Alex Abbott U.S. Fish and Wildlife Service Meredith Bartron U.S. Fish and Wildlife Service Ed Baum Atlantic Salmon Unlimited Chris Holbrook U.S. Geological Survey Dan Kircheis - NOAA John Kocik - NOAA Tim Sheehan NOAA Tara Trinko Lake - NOAA Jed Wright U.S. Fish and Wildlife Service 16