WHAT’S HAPPENED TO ALL The COD? 1 Tan squares = tagging sites. Red dots = capture sites. Were Maine’s rivers Involved? Adult alewives migrate south in the fall… … Only YOY alewives stay behind. From: www.codresearch.org and GMRI 2 Coastal cod collapsed in the 1870s. Baird maintained it was because dams had destroyed alewife runs in rivers… and cod lost their prey! Has this happened again? Let’s check… US Commissioner of Fisheries Spencer Baird Alewife landings dropped by 1/2, Herring by 2/3 in 1962… In a single year! Were cod lost at the same time? 6 Muscongus Bay Cod Muscongus Bay cod collapsed in the early 1960s. It also had 2 small alewife rivers and a cod spawning group that Western Penobscot Bay Matinicus Seal Island Eastern Casco Bay Muscongus Bay IN FALL: ME-NH trawl surveys show YOY alewives from the Damariscotta and St. George Rivers gathered in these two circles. Where were cod in the fall? Muscongus Bay Monhegan Island 1930s fishermen identified two cod spawning grounds in Muscongus Bay (Ames 1997) St. George River Damariscotta River Muscongus Bay YOY Alewives YOY Alewives When plotted on a chart, the 1930s spawning grounds were located inside the two circles! It gets better… Muscongus Bay IN THE 1920S, Cod, haddock, pollock and hake moved inside the two circles… EVERY FALL! 1 BUT… The cod are gone. So are the haddock, white hake, pollock and winter flounder! 3 Is this the end of New England’s fabled 4 coastal cod fishery? Only if we ignore the obvious: 14 The Summary... • 1870s Historical Cod left the shore when dams were built and Alewife runs collapsed. • 1960s Cod left Muscongus Bay when YOY Alewives and juvenile Herring dropped sharply in single year. • 1990s Cod left Jeffries Bank when Penobscot Bay herring became overfished… And cod disappeared from the northern half of New England’s coast. And here’s today… The Kennebec & Penobscot Rivers are reopened!! Edwards Dam Removed Great Works Dam Removed Kennebec River Penobscot River • Opened in 2000 • Opened last year • Now, 3.2 million alewives per • Projected production = spawning run and growing. • 10-12 million alewives. And they’ll produce a lot of fingerlings for winter prey… ST. CROIX PENOBSCOT KENNEBEC Here’s the three fishing areas that would be affected by a recovery of alewives… The question… Will cod re-establish their inshore spawning grounds? First you lost YOY alewives and/or JV herring… • Then you lost local spawning group… one by one. • Then you lost local reproduction • Then you lost juvenile cod because there wasn’t enough small prey • Then, after awhile, you lost a subpopulation… • Then another subpopulation .