Big Thicket: A Forest of Diversity

After our first night staying at the Big Thicket Field Research Station, the crew was up early for our first field experience in East Texas. The class was divided up into two vans, one with six students and the other with eight. The van I was included in was the fifteen-passenger van with eight students guided by Professor Williams. Being with Dr. Williams, our group learned about fresh water fishes that day. Our first destination of the day was near Dallardsville, TX in the Big Sandy Creek Unit. We had been granted a permit that allowed our class to sample fish within the Big Thicket. The first stream we had sampled was Big Sandy Creek. We sampled near the Woodlands Trail and Sunflower Road. The next water body sampled was within the Turkey Creek Unit, along Turkey Creek. To get there we traveled along highway 943 and turned north onto 69-287. This brought us northward passing through Warren, TX, and eastbound to the Turkey Creek Trail. This was our first site in this unit, but we were not able to access the creek from the trail we had walked, forcing us to turn around and walk back to the van empty-handed. Our trek totaled at about three miles. We had visited a few more sites within this unit to sample.

Our sampling methods for freshwater included seines and a Smith-Root backpack electro-fisher. To seine fish, one needs waders and two others for assistance. Two people will be on either side of the seine, holding the brail poles. On a seine, there is a float line on top and a lead line on the bottom. The lead line holds the net on the bottom of the creek bed, restricting fish from escaping the net. As the two individuals pull the seine downstream, fish will accumulate within the net. Pulling the seine downstream is essential, as fish move upstream to avoid predators. It is also difficult to pull a seine against the current. Once the seine has been pulled downstream for about ten yards, it will be pulled out of the water to view the catch. The third person will be trailing the seiners to collect the fish specimens.

Backpack electro-fishing is a great way to sample for fish in shallow streams. It is called a backpack electro fisher because one will wear it strapped onto their back. Attached to the device is a cathode and anode, allowing electrical current to flow through the water column. A battery that is secured to the bottom of the electro fisher gives the device power. The anode would be the part that controls the electric current, and has a round ring at the end to move throughout the water. The cathode is called a “rat tail” on this backpack electro fisher. The rat tail needs to be in the water out in front of the person running the device. Along with the person wearing the device, there will be at least two other individuals to net the fish and carry the bucket with the specimens contained within. The people with the nets oversee adjusting the voltage output, as each stream has different conductivity which affects the electric current. Adjusting the voltage is as easy as turning the knob up or down as needed. Safety is important and everyone needs to be attentive. The backpack has a “kill switch.” This activates if the person wearing the device even bends over too far, which is a great safety feature.

After a long day of sampling, our group was successful in capturing various fish species. These species included bluegill, red-eared sunfish, long-eared sunfish, spotted sunfish, spotted bass, warmouth, pirate perch, topminnows, pickerel, mosquitofish, log perch, ghost shiner, gizzard shad, red shiner, pug-nosed minnow, and even large tadpoles. (I don’t have photos of all the fish but I will include what I can!) After identifying all the species we had caught, we headed back to the Big Thicket Field Research Station to gear up for another busy day the next day. Our night ended with a home cooked meal of spaghetti. Today was an experience I will never forget! Being exposed to all the new fish species really opens a door within the fisheries world.


Here is a map of the Big Thicket National Preserve. It will help you get an idea of where we were sampling fish.


Long Eared Sunfish

Pirate Perch

Top: Bluegill

Bottom: Unidentified Hybrid Sunfish


Spotted Bass

Orange Spotted Sunfish

Redfin Pickerel

Red Shiner

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