Managing our aquatic natural resources in a way that keeps our state’s fisheries vibrant into the future is a big part of our department.
But in order to make the best management decisions, the best data and analysis is necessary.
That’s where the LDWF stock assessment team plays a critical role.
A stock assessment is an estimation of the amount of fish available in the population and the rate they are removed by the fishery. It is the traffic light, if you will, doing its part to curb overfishing.
When the light is green, you’re free to go. Just like when a fishery is stable, you’re free to fish to your heart’s content (or until you’ve reached the bag limit in some cases).
But the yellow and red lights are for your safety, and although they can be an aggravating nuisance, they protect vehicles from themselves. In the same vein, the stock assessment team accesses the fishery and protects anglers from themselves by making recommendations to fishery managers, which in turn enact rules and regulations to protect the fishery they love so much.
In order to develop a stock assessment, the team needs three vital pieces of information.
First, a measure of abundance or how many fish are available for capture is needed. This information is acquired through LDWF’s fishery independent surveys, an ongoing, in-house effort to assess populations in question.
Next, the stock assessment team needs information on how many fish have been removed from the population by the fishery. That information comes from LDWF’s LA Creel Survey of recreational fishermen and Trip Ticket Program on the commercial side of the fishery.
Finally, the team needs biological information on the species being analyzed – such as how fast it grows, reproductive rates, natural mortality rates and movement. This information is primarily acquired from LDWF’s biological sampling program which provides species-specific biological information in support of stock assessments.
After acquiring all three pieces of information, the team inserts the information into stock assessment models, which aim to determine fisheries’ effect on the population of the specific fish in question whether it be blue crab, spotted seatrout, black drum, sheepshead, southern flounder or striped mullet – all fish analyzed in LDWF stock assessments.
The result of each stock assessment allows fishery managers to determine whether a certain species is undergoing overfishing or if it has been overfished. Overfishing is when fish are being removed at an unsustainable rate, and once a population has been depleted to undesirable levels it has been overfished.
