Another surprise was the discovery of drifting eggs as late as September, contrary to previous belief that the spawning season ends in July.

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Thames Water had initially looked at draining the lake to make the repair but this was ruled out as the fish are in spawning season.

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In the Winnebago system, the fish were helped by state laws and a period in the 1970s and 1980s when the polluted waters were so murky that they were hard to catch, except during the spawning season.

WSJ: Standing Guard for the Sturgeon

Gulf shrimp are in their spawning season.

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Female sturgeon don't become sexually mature until their 20s and spawn about every four years, so the spawning season, in which they surface from the depths to lay their eggs on rocky shores, is an extremely important time for the species.

WSJ: Standing Guard for the Sturgeon

Spawning is one such season.

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Having identified the main Loligo nursery grounds, they recommended postponing the opening of the fishing season in these areas for a few months after summer spawning.

ECONOMIST: Conservation in the Falkland Islands