When I was a kid... (I'm 43 now

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Winter Flounder were so plentiful where I'm from (L.I. Sound West), I used to catch them as an inexperienced kid, using self- dug Nightcrawlers, freshwater (Kirby)- type hooks, & freshwater rods & reels... anytime starting today! (St. Pats. Day was our "Flounder opener" each year...

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Doing everything "wrong" & with no boat & no chum at all... we'd still get 6- 12 fat Flounder for a days effort, all fish from 12- 17+ inches (we kept only 12" or better even back then with liberal limits). 2.5 lbers. were common for us... & I saw some way bigger caught! We used to catch them at low tide straight down under a dock in only 3- 4 ft. of water, where you could see them approach the bait-- big ones too!
Same places these days-- you MIGHT get a few under 10" for that same days' fishing, using a boat & doing everything "right!"
Lots of theories abound as to why the demise of Winter Flounder more so than other heavily- pressured species has occured. To me the explanation is the proliferation of another species now beyond all control, exactly as the Flounder stocks dwindled! In one word: CORMORANTS!