It is not uncommon in March, April, and May on high tides in the morning to catch big numbers of male flounder entering the lake, says Sabine Lake guide Skip James. Through tagging studies he conducted, James found that local flounder trade into the Sabine Lake ecosystem in March, about four days before the full moon. James says they come through the Gulf pass and into the Intracoastal Waterway that feeds up along the western side of the lake. The fall migration is sudden and abrupt, whereas the spring migration of southern flounder is very gradual, James says. During the spring flounder run, the Causeway Bait Shop on the south end of Pleasure Island is well located to provide information on the movements of gamefish.
Trout also migrate into Sabine Lake in the early spring months.
James notes that every now and then anglers targeting flounder will locate nomadic trout running through the pass. During March and April James recommends that flyfishers work the south end of the lake because the salt content there is more favorable and the water is deeper. This area of the lake contains submerged rocks and other substructures as well as reefs with ridges and points going out into deep pools, challenging the flyfisher's casting skills. James advises flyfishers to use sinking lines and shooting heads around the deep drop-offs and reefs. By early May, flounder are fully distributed throughout Sabine Lake all the way up to the river mouth.