Black drum were sampled in 2011, 2012, and 2013, but numbers were only sufficient for length class analysis in 2013.
In 2011, the mean condition factor for black drum in Calcasieu Lake was 0.934 +/- 0.017. This means that the black drum only had enough forage to maintain 93.4% of the weight as the long term Louisiana average for a given length, season, and species. For comparison, the condition factor determined by the USGS in 2000 (before the oyster reefs were destroyed) was 1.03 +/- 0.02. In 2012, the mean condition factor for black drum dropped markedly to 0.842 +/- 0.012. In 2013, the mean condition factor of all lengths was 0.889 +/- 0.012.
The length class analysis shown in the graph shows that the longest length classes are struggling to find enough food to maintain body condition. These are the fish most heavily dependent on oyster reefs, suggesting that oyster reef destruction (by dredging) is a significant factor in the observed declines in fish condition.
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