Wiktionary(0.00 / 0 votes)Rate this definition: upthrust(Noun) an upward thrust. upthrust(Noun) buoyancy. upthrust(Noun) an upward movement of part of the Earth's crust. upthrust(Verb) to thrust something upwards.
Predators, Food and Feeding: Natural predators of winter flounder include sharks, oyster toadfish, summer flounder, striped bass, monkfish and spiny dogfish. When feeding, a winter flounder will lie motionless, partly concealed on the bottom, with its head raised off the bottom, braced by the dorsal fin.
Winter flounder in eel grass. Photo credit: Carl Lobue, The Nature Conservancy. The Commission and the New England Fishery Management Council jointly manage winter flounder with complementary management plans that regulate state and federal waters based on fisheries and the biology of winter flounder.