ANNUAL REPORT OF THE U.S. ATLANTIC SALMON ASSESSMENT COMMITTEE REPORT NO. 30 - 2017 ACTIVITIES Portland, Maine February 26 – March 2, 2018 Artwork Courtesy of Caroline Côté @C_LCote 2018 PREPARED FOR U.S. SECTION TO NASCO Table of Contents 1 Executive Summary ............................................................................................................................. 4 1.1 Abstract ......................................................................................................................................... 4 1.2 Description of Fisheries and By-catch in USA Waters ................................................................... 4 1.3 Adult Returns to USA Rivers .......................................................................................................... 5 1.4 Stock Enhancement Programs ...................................................................................................... 7 1.5 Tagging and Marking Programs .................................................................................................... 7 1.6 Farm Production ........................................................................................................................... 7 1.7 Smolt Emigration ........................................................................................................................... 8 2 Viablity Assessment - Gulf of Maine Atlantic Salmon .................................................................... 24 2.1 Overview of DPS and Annual Viability Synthesis .............................................................................. 24 2.1.1 Change in Status Assessment Approach .................................................................................... 24 2.1.2 DPS Boundary Delineation ......................................................................................................... 24 2.1.3 Synthesis of 2017 Viability Assessment ..................................................................................... 25 2.2 Population Size .................................................................................................................................. 27 2.3 Population Growth Rate ................................................................................................................... 30 2.4 Spatial Structure of DPS .................................................................................................................... 33 2.4.1 Wild Production Units – Redd Counts ........................................................................................ 34 2.4.2 Hatchery Production Units – 2017 Cohort ................................................................................. 36 2.5 Genetic Diversity ............................................................................................................................... 38 2.5.1 Allelic Diversity ........................................................................................................................... 39 2.5.2 Observed and Expected Heterozygosity .................................................................................... 40 2.5.3 Effective Population Size ............................................................................................................ 40 2.5.4 Inbreeding Coefficient ............................................................................................................... 40 2.5.5 Summary .................................................................................................................................... 40 2.6 Literature Cited ................................................................................................................................. 41 3 Long Island Sound ............................................................................................................................ 44 3.1 Long Island Sound: Connecticut River ......................................................................................... 44 3.1.1. Adult Returns ............................................................................................................................ 44 3.1.2 Hatchery Operations .................................................................................................................. 45 3.1.3. Stocking ..................................................................................................................................... 45 3.1.4. Juvenile Population Status ........................................................................................................ 46 USASAC ANNUAL REPORT 2017/30 1 3.1.5. Fish Passage .............................................................................................................................. 46 3.1.6. Genetics .................................................................................................................................... 47 3.1.7. General Program Information ................................................................................................... 47 3.1.8. Migratory Fish Habitat Enhancement and Conservation .......................................................... 47 3.2 Long Island Sound: Pawcatuck River ................................................................................................. 47 3.2.1 Adult Returns ............................................................................................................................. 48 3.2.2 Hatchery Operations .................................................................................................................. 48 4 Central New England: ....................................................................................................................... 49 4.1 Merrimack River ................................................................................................................................ 49 4.1.1 Adult Returns ............................................................................................................................. 49 4.1.2 Hatchery Operations .................................................................................................................. 49 4.1.3 Juvenile population Status ......................................................................................................... 50 4.1.4 General Program ........................................................................................................................ 50 4.2 Saco River .......................................................................................................................................... 51 4.2.1 Adult Returns ............................................................................................................................. 51 4.2.2 Hatchery Operations .................................................................................................................. 51 4.2.3 Stocking ...................................................................................................................................... 52 4.2.4 Juvenile Population Status ......................................................................................................... 52 4.2.5 Fish Passage ............................................................................................................................... 52 4.2.6 Genetics ..................................................................................................................................... 52 4.2.7 General Program Information .................................................................................................... 52 4.2.7 Migratory Fish Habitat Enhancement and Conservation ........................................................... 52 5 Gulf of Maine ........................................................................................................................................ 53 5.1 Adult returns and escapement ......................................................................................................... 55 5.1.1 Merrymeeting Bay ..................................................................................................................... 55 5.1.2 Penobscot Bay ............................................................................................................................ 56 5.1.3 Downeast Coastal ...................................................................................................................... 58 5.2 Juvenile Population Status ................................................................................................................ 64 5.3 Fish Passage and Migratory Fish Habitat Enhancement and Conservation...................................... 71 5.4 Hatchery Operations ......................................................................................................................... 83 5.6 General Program Information ........................................................................................................... 91 6 Outer Bay of Fundy ............................................................................................................................. 92 USASAC ANNUAL REPORT 2017/30 2 6.1 Adult Returns .................................................................................................................................... 92 6.2 Hatchery Operations ........................................................................................................................