Calcasieu Relative Condition Factor Study 2012 Preliminary Results

[Duck Butter]

Originally Posted by MathGeek

Great points. Let me add the over harvesting of the oysters.

Determining what is happening with the fish stocks is generally much easier than ascribing causal factors definitively. Yet, the Callihan thesis seems to indicate that a stock assessment would be determining the impact of the change to the limits rather than any of the possible confounding factors that has been suggested:

Interestingly, Louisiana recently adopted (in 2006) a spatially-explicit management plan for Calcasieu Lake. The premise of this management decision, which included a reduction in daily bag limits and imposition of a slot limit, was to ‘preserve’ the renowned trophy-fishery for spotted seatrout in Calcasieu Lake. However, the decision to enact this regulation was based exclusively on socio-economic factors, rather than the biological status of the subpopulation. In fact, no formal stock assessment was conducted as part of the decision-making process. Thus, the status of the subpopulation (stock) was largely unknown (i.e., overfished or not?) at the time regulations were changed. While perhaps setting a bad precedent for fisheries management (i.e., making a decision based purely on socioeconomic reasons), this situation affords a unique opportunity to evaluate the response of spotted seatrout to a spatially-explicit (estuarine-scale) regulations change (i.e., adaptive management, sensu Hilborn and Walters 1992).

from Callihan PhD thesis LSU 2011 p. 182

Oyster overharvest would be very good to add