| Summary: | The increase in the abundance of gray snapper (Lutjanus griseus) in Texas bays and estuaries over the past 30 years is correlated to increased wintertime surface watertemperatures. Trends in the relative abundance of gray snapper are evaluated by using monthly fishery-independentmonitoring data from each of the seven major estuaries along the Texas coast from 1978 through 2006. Environmental conditions during this period demonstrated increasingannual sea surface temperatures, although this increase was not seasonally uniform. The largest proportion oftemperature increases was attributed to higher winter temperature minimums since 1993. Positive phases of the North Atlantic Oscillation, resulting in wetter, warmer winters in the eastern United States have occurred nearly uninterrupted since the late 1970s, and unprecedented positive index values occurred between 1989 and 1995. Increases in water temperature in Texas estuaries, beginningin the early 1990s, are postulated to provide both favorable over-wintering conditions for the newly settledjuveniles and increased recruitment success. In the absence of cold winters, this species has established semipermanent estuarine populations across the entire Texas coast. A shift to negative phases of the North Atlantic Oscillation will likely result in returns to colder winter temperatureminimums that could reverse any recent population gains.
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