Fisheries Management: Casting Nets and Balancing Budgets

Have you ever wondered about a fisheries manager’s decision-making process? Or how they come to the conclusions they do? There is a delicate balance in creating a bountiful fishery while ensuring the sustainable harvest of key recreational species. It is similar to balancing a budget, the best outcomes result from tracking your spending and allocating enough funds for the future and for emergencies. Similarly, managing a fishery means optimizing opportunity and allowing harvest levels that still support resilient and sustainable populations. Granted, having exact counts of fish in a population is a tall order, but consistent monitoring helps paint a picture of a population and this picture assists in making sound management decisions. A substantial effort goes into collecting data through Texas Parks and Wildlife’s (TPWD) sampling programs. This enables fisheries managers to paint an accurate picture that informs size or bag limits, fishing gear restrictions, and fishing closures to try and ensure sustainable fish populations are here to stay.

One goal that resource management agencies and fishermen have in common is maintaining access to as many fish as possible. For fisheries managers, there are limited tools available to ensure that conservation goals are met, while providing positive fishing opportunities to the angling public. Staff within the Coastal Fisheries Division of TPWD conduct monthly resource monitoring sampling in Texas bays using a variety of gears. This sampling helps to identify population trends in young of year, juvenile, and adult fish populations. Another tool, creel surveys, collects data that paints a picture of harvest and observed fishing pressure as well as angler satisfaction within the fishery. The trends produced from this data can help to identify a regulatory need and initiate the formal process of implementing new regulations and/or changing existing regulations. The Coastal Fisheries Division at TPWD boasts 40+ years of continuous sampling efforts to monitor these populations and inform trends and action. This long-term monitoring has been incredibly beneficial in achieving shared goals.

Sometimes, negative long term data trends are enough to constitute a call to action from fisheries managers. In other cases, unusually severe events, such as Winter Storm Uri, may alert resource managers to watch for negative trends in certain fish populations that can be susceptible to large scale mortality during cold weather events, like Spotted Seatrout. In the budget analogy, these trends could be compared to decreasing funds or emergency expenditures, respectively. Once the potential need for regulatory change is identified, the public is asked to provide ideas and input through scoping meetings. If a certain management action is identified and regulatory change is deemed necessary, an official proposal is drafted and presented to the public, before ultimately being decided on by the Texas Parks and Wildlife Commission. This fisheries management process can be demonstrated through two recent management actions within two popular sport fisheries: Spotted Seatrout and Southern Flounder.

In the case of Spotted Seatrout, a combination of fish kill estimates and gillnet data after Winter Storm Uri prompted emergency actions in the Laguna Madre. This eventually expanded to temporary regulation changes from Matagorda Bay southward. For these areas, the coastwide 15-25 inch five-fish limit with one oversize seatrout gave way to a 17-23 inch three-fish limit with no oversized seatrout allowed. These emergency and temporary regulations were implemented to reduce harvest and conserve the number of spawning seatrout, recruiting more fish to the population in the long run. It might be thought that the best approach would be to reduce the maximum legal size, protecting larger spawning females. However, as fisheries managers, it’s important to consider just how many fish you’ll be protecting in a specific population. Figure 1 shows the size distribution of Spotted Seatrout caught in gillnets along the coast between 10-36 inches. More than half of the coastwide Spotted Seatrout population falls between 15-18 inches in length. With this information, decision makers can pursue regulation changes that would protect the half that most likely contained spawning females while still offering a positive fishing experience. For example, a 15–20 inch slot limit offers anglers a good opportunity to catch and harvest Spotted Seatrout, while also protecting valuable spawners.

Another case study demonstrating how management tools can help to conserve a species is the implementation of the harvest closure period for Southern Flounder. In the last decade, Southern Flounder populations along the Texas coast have experienced a steady decline. In the winter, Southern Flounder primarily display migratory behavior, exiting shallow bays and heading into the Gulf of Mexico (Gulf). Widely referred to as the “Flounder Run,” these fish congregate in narrow passages to the Gulf, rendering them more susceptible to fishing pressure and harvest. Due to the long-term population declines, regulations were changed, and in 2021, the harvest of southern flounder was prohibited from November 1^st to December 15^th. TPWD resource sampling procedures allow us to examine population trends and help us determine the effectiveness of management strategies including new regulations. Figure 2 shows the coastwide fall gillnet catch per unit effort (CPUE) of southern flounder from 1982-present. An increase in total catch can be observed during the fall of 2021. By allowing these flounder to safely make passage to the gulf, the hope is that the population will experience an increase in spawning stock biomass. This is an excellent example of how management strategies can be species specific. In the case of Spotted Seatrout, which lack a distinct migration pattern, the regulation targeted harvest pressure where the breeding population could be conserved. In the case of Southern Flounder, which possess unique migration behavior, management strategies target their vulnerability in a specific life history event. TPWD hopes in both cases, that being responsive and proactive in management strategies will yield positive, recovering trends for Spotted Seatrout and Southern Flounder.

Ultimately, the desires and goals of both fisherman and resource management agencies often align. While natural disasters and other uncontrollable events occur, effective use of management tools such as slots, limits, or closures can have profound effects on fish populations. Like a financial budget, budgeting for better seatrout, flounder, or other fisheries faces numerous scenarios and obstacles to consider and overcome. Whether it's money or fish, resource managers are using the best available information to most effectively respond to negative trends and unexpected events. While the approach and strategy can differ, TPWD is committed to managing Texas’ fisheries so that future generations can continue to have strong and vibrant fisheries for years to come.