Lessons from the Hip
By Bob Lusk
Plus, I see things few people ever get to see.
Okay, here’s the deal. I have to own this.
We’ve built a new world headquarters, the last office we’ll have under my watch, and with all the regular pond management and consulting business, along with being watchdog over this new construction, ‘ol Word-Dog Bob here has once again allowed himself to be just a tad bit overwhelmed. So, in the spirit of deadlines, and not having to dig deep into the subject matter at hand, it dawned on yours truly to just shoot from the hip on this one. Share some recent biological happenings and just toss them out there for your entertainment.
As a consulting biologist, I get to travel quite a bit, help people design new lakes, figure out what to do with older ones, and come up with advice about what to do—and how to do—what they need to meet their pond/fishery goals. Then, we put those ideas to work.
It’s really fun.
Plus, I see things few people ever get to see. For example, while recently driving through an Oklahoma ranch, talking with the owner about ways to improve each of his several ponds, I saw a long-haired cow with crooked horns, almost forming an “S” across the thing’s head. It’s a smaller animal, with hair almost dragging the ground. I must’ve had a weird look on my face, because mid-sentence, the owner said, “Yak.” Who knew? I didn’t. A yak, in the middle of the ranch. I literally see abundant wildlife on many properties, but this was a first. Lesson? It’s normal for landowners to manage their land, water, and animals in creative ways.
A few weeks ago, during our fall electrofishing surveys, we captured a significant number of bass from a lake northwest of Fort Worth, Texas. As the biologists were weighing and measuring fish, and logging the data, they came across one particular bass with a bulging belly. One of the guys looked down the gullet of the fish and saw a tail protruding from this fish’s throat. And, it wasn’t a fish tail, either. It was the tail of a rodent. He gave it a little tug, and out came the furry critter. Lesson? Bass will eat anything in the water, as long as it is moving and fits its massive maw. A bass has no conscience.
Another time, as my team and I were collecting fish via electrofishing, one particular fish caught my eye. This one, a big bluegill, had an abnormal look in its eye. As I took a closer look, the pupil seemed to have a maze in it, not the normal black color. As I gazed into its eye, the maze moved. I had a small Exacto knife and some tweezers, so we did a little operation. I lanced the fish’s cornea and started pulling on that maze. It was a worm, a nematode-looking worm. The more I pulled, the more came out. The more came out, the more I pulled. As you see in the photos, there was a lot of worm in that fish’s eye. It turned out to be a nematode, a parasite. Not being a fish pathologist, I had to rely on what I could find online. That particular nematode looks like Eustrongylides, a worm transferred into waters via birds, usually wading birds. The bird eats an infected fish, flies away, and deposits parasite eggs via feces. Aquatic worms eat the eggs, and become the first host. The worms grow inside its host worm—sounds a little complicated, doesn’t it? A fish like our bluegill eats the aquatic worm that is hosting the parasitic worm. Then, the parasite survives the digestive system and infects organs in this host. That worm migrated into the fish’s eye, from the inside. Then, a bird eats the fish, flies off to the next pond and the cycle starts again. Lesson? Parasites are common, transferred in a variety of ways. As a biologist, I consider parasites a normal consequence of nature.
As we did more field work in October, we were able to catch some tilapia in one lake. In our part of the planet, we stock tilapia in select lakes each spring. Tilapia, an exotic species, serves two unique purposes in our region. First, we can only stock Mozambique tilapia by permit here in Texas. We have to have a permit, not the landowner. At the end of the year, we file a report of our stockings to the state. The mission is to use these fish to minimize filamentous algae, and bolster survival rates of baby bluegills. Here’s how that works. In spring months, when water temperatures rise into the lower 70’s, we stock tilapia that weigh at least a quarter pound, and are plenty big enough to spawn. As the babies hatch, daddy tilapia holds them in his mouth until they absorb their yolk sac. Then, he spits them out, wishes them luck, and gets another batch of eggs to hatch. The babies head for algae, feed on it, and grow. Often, small tilapia end up in the food chain, as they are small and easy prey, and the more tilapia that are hatched, the greater the odds baby bluegill have to survive. Looking at the numbers, tilapia spawn continually in our warm waters. Bluegills spawn about every 45-60 days. Just for comparison, say a given pond receives 100,000 baby tilapia, spawned over a season. Say that same pond has a similar number of bluegills hatched during the same period. Statistically, odds of bluegill survival rise, simply because of sheer numbers of fish hatched. Realistically, that’s what happens. In ponds and lakes where we stock tilapia, we see increased survival of young of the year bluegills during our fall electrofishing surveys. Plus, the originally stocked tilapia grow rapidly, and if you can figure out how to catch them before they succumb to cold temperatures, you’ll have excellent table fare. Mozambique die when water temps drop into the low 50’s. They serve their purpose, and then die. While that sounds a little callous, I’ve received phone calls from clients telling me that when their tilapia die, there aren’t that many, and in some parts of Texas, bald eagles converge to feed on the carcasses. Not one time have we seen dead tilapia as an issue. Conversely, if they were to live, we’d trade problems by having fish taking up space and becoming competitive rather than filling a special need. Lesson? Some species of fish serve specific purposes in your waters. Your job is to understand those species and decide if they fit a need in your waters.
One client, a man whose passion for his land is evident by the ear to ear smile across his face, decided to design and build his very own lake. He and his bride studied their newly acquired parcel, worked with an earthmover, and figured out the best place to build a dam. They enlisted my services to consult how to design the habitat inside the lake basin to make a nice bass fishing lake. We had an initial meeting, I wrote down some thoughts, and left it at that. There were quite a few delays, and I went about my business. It didn’t dawn on me to ring his number and stay in touch. Remember the first paragraphs in this story? I did manage to meet with the earthmover a few times and knew that work was progressing. But, with my mind occupied, I didn’t think about calling the landowner to hear his thoughts about lake basin design as construction progressed. One part of me expected to receive a phone call, but the businessman in me knew I should’ve called. I didn’t. When the call came, the earthmover was nearing completion and ready to move off to the next job. I drove the 30-something miles, took a look, and saw quite a few things that still needed to be done. There was a peninsula to build, some humps to create, and structure to be added. Slopes needed adjusting on two shores, and more artificial fish attractors needed placement.
Then, when I came for a final inspection two weeks later, there wasn’t nearly the volume of habitat I expected to see. Water was beginning to collect in the lake basin, the earthmover was gone, and more structure was needed. The landowner understood the concepts and needed to use his passion and drive to do more to create the underwater community he wanted for a thriving fishery—and do it before the next rains. I felt a sense of urgency.
But, the thing that bothered me most was the remnants of a pond, smack dab in the middle of the project. That little mudhole was likely home to some unwanted species of fish. The landowner told me that a neighbor youth, a teenager, claimed that little hole was full of bullhead catfish. With a well-placed dam, thoughtful habitat development and placement, this couple had one chance to do this project properly. We’d discussed this mudhole in our first conversations, and everyone knew it needed to be completely drained to get rid of unwanted fish. That didn’t happen.
Now, here we were, lake beginning to fill, more fish attractors needed, and we had no idea if there are unwanted fish present. That’s a problem. It would take more than $750 to buy a fish toxicant and take out fish that might not exist. The decision was made to buy a fish feeder (which he’ll need anyway) and see if any fish come to a consistent feeding program. If they do, and are unwanted species, then we’ll take them out. If not, we’ll plan to stock the lake and move forward with the original program. Lesson? Communication is crucial. Building the perfect fishing lake is a progression of events, and things can go wrong with each step.
This pond management thing is always interesting and keeps guys like me on our toes. No matter how much I’ve seen, it seems there’s always something new.