The Trials and Tribulations of Trout Management
Have you ever come back from a fishing trip and been approached by a group of people in khaki uniforms holding a clipboard, basket, and measuring board? A common assumption is that game wardens are approaching, but that is not always the case. Usually, these individuals are staff from the Texas Parks and Wildlife Department - Coastal Fisheries Division (TPWD-CF). Local anglers on the Texas coast are used to these encounters, but they may not be familiar with how staff use the information collected and the importance of their work.
Coastal Fisheries staff conduct “creel” surveys (or angler surveys) at boat ramps along the Texas coast. Staff ask anglers a variety of questions such as what county you reside in, how long you spent fishing, how many and what kind of fish you kept, and what species you were targeting. TPWD-CF’s goal with these questions is not to expose anglers’ secret fishing spots, but to gather information to generate an estimate of what is being harvested from Texas waters. In addition to creel surveys, TPWD-CF also collects data on fish populations using bag seines, trawls, oyster dredges, and gill nets. Anglers occasionally express concern over the use of these gears, but staff go to great lengths to minimize any impacts to the resource. While some mortality does occur, these “tools of the trade” are an essential part of research and fisheries management. Field crews strive to expedite the process and release fish alive, minimizing mortality. One type of sampling gear that most anglers are familiar with are gill nets. Gill nets target adult fish and are used for 10 weeks in the spring and 10 weeks in the fall. Random selection of locations is used to eliminate bias when setting gill nets. The data collected from gill net surveys give TPWD-CF biologists information regarding population abundance, lengths of fish sampled, and species composition. Comparing current data to previous years' data can help biologists to understand the dynamics of a population over time. Additionally, TPWD-CF can utilize both gill net sample data and creel survey estimates to better understand what is happening in Texas bays, which informs management decisions and helps form regulations that ensure sustainable levels of harvest.
TPWD-CF utilizes gill net catch data and other sampling data to better understand how major Texas freezes impact Spotted Seatrout populations, a popular species that many anglers ask about at creel surveys. For example, the February 2021 freeze caused significant seatrout mortality on the middle and lower coast as seen in reduced catch rates in Spring 2021 gill nets. Although it takes time, TPWD-CF is starting to see signs of recovery in spotted seatrout populations, as evidenced by data collected from subsequent gill net surveys (Figure 1).
Figure 1 shows the gill net catch rates, which is the number of trout caught per hour that the net is in the water. In 1983, 1989, and 2021 there were significant freezes that impacted the catch rates in gill nets the following spring. In spring 2020 there is a data gap because sampling was suspended due to the pandemic, but in spring 2021, the catch rate for Spotted Seatrout was much lower than in previous years as a result of freeze impacts.
Figure 2 shows the effects of the freezes of 1983, 1989, and 2021 on Spotted Seatrout harvest. The reduction in trout harvest could be caused by several different factors. Anglers may not be catching or targeting trout, or they might not be keeping as many trout due to concern over trout populations or emergency regulation changes. Tournaments could also be impacting data if they are not targeting trout, or the tournament is catch and release.
The data collected through monitoring efforts allow biologists to see that Spotted Seatrout populations recovered within two to three years after the 1983 and 1989 freezes, underscoring the value of collecting this data. After the 2021 freeze, TPWD decided to implement an emergency regulation that reduced the bag limit of Spotted Seatrout to three fish per angler, with a minimum size of 17”, a maximum size of 23”, and no “oversize” fish allowed. This regulation is in effect from FM 457 near Sargent, Texas south to the Texas/Mexico border, the area in which trout were most impacted by the freeze. This regulation is set to expire and revert back to the previous bag and size limits on September 1, 2023. The previous regulation was a bag limit of five fish per angler with a minimum size of 15”, a maximum size of 25”, with one fish allowed over 25” per day. Some anglers have had questions and concerns regarding TPWD’s decision to implement these emergency regulations, but the data gathered from gill net surveys and creel surveys informed the decision to implement the emergency regulations and helps to answer anglers’ questions. The rationale behind these regulations was to allow at least two spawning seasons that limited the harvesting of smaller trout, giving them the chance to grow and reproduce, bolstering population recovery. Through continuous monitoring, TPWD hopes to see the benefits of responsive management through a fully recovered Spotted Seatrout population. Furthermore, TPWD hopes to see anglers benefit from these efforts through continued high quality fishing experiences along the coast.