It is Friday, let me get up a quick blog post before the weekend. . . .
You all know I am fascinated by predator/prey interactions, especially those that occur below the surface of the water. This week our Ak-Sar-Ben Aquarium posted a video on their FaceBook page. You need to watch it!
I love going to aquariums, especially our Ak-Sar-Ben Aquarium where I can see Nebraska fish! I can stand and watch fish in an aquarium for hours, and in spite of visiting the Ak-Sar-Ben Aquarium hundreds of times, I am always up to go back again! For as long as I can remember there has been at least one ginormous blue catfish on display there. I have been present during a few feeding times to observe, and it is fascinating. Much of the time, the big blue cat in that tank sits on the bottom, resting, conserving energy. When that big fish is on the move, it is not fast, not helter-skelter, it is relatively slow, and if you observe, it is a slow, deliberate cruise. Watch the video. That big blue is cruising along the bottom of the tank, not necessarily pursuing prey, but trying to work itself into position where some poor, unsuspecting trout, or goldfish, whatever the feed of choice is for that day, is positioned where it cannot escape. Yes, you could say it is trying to corner its prey, put it in position along the bottom or even up against a side where ole blue knows he or she is gonna eat. “Slurp, crunch, belch”–Life is Good!
I have blogged about how being able to visualize what is happening below the surface can make you a better angler (Visualization). You can learn a lot about the feeding behavior of big catfish by studying the video of big blue inhaling that trout. It is Optimal Foraging Theory in action!
Also notice how the prey is actually captured. Most of our large predator fish actually open their mouths AND flare their gill covers at the same time. You need super slow-motion to see what happens, but in that instant when a strike occurs, a volume of water is actually sucked into that predator fish’s mouth and if they have positioned themselves properly, their prey item cannot escape. It is sucked in along with that prey. Now a blue catfish the size of the one on display at the Ak-Sar-Ben Aquarium is sucking in an incredible amount of water when it makes a strike. It is awesome to see it happen.
I was there one time when a big blue ate a 10-12-inch feeder goldfish in that aquarium. The goldfish made the mistake of getting positioned up against the glass of the aquarium and the blue nailed it, inhaled it right off the side of the glass. I was standing just on the other side of that glass and when it happened. First, it happened in the blink of an eye, and I thought the big cat was going to suck the glass right out of the wall of the aquarium. In an aquarium tank that size, the glass is relatively thick, not like the glass in your windows at home. You could hear a very audible “thunk” when the cat made its strike, but it was NOT a “thunk” from hitting the glass, it was a “thunk” from the inhalation of the gold fish. Watch the video above and you will get an idea what I am talking about when that blue cat eats the trout.
On the occasion that goldfish got ate, when I blinked because I did not believe what I had just witnessed, there were a few goldfish scales slowly fluttering towards the bottom–the only evidence of the awesome predator/prey drama that had just happened in that instant.
For some reason folks naturally empathize with the “poor little fish”, or the “poor little” Thomson’s gazelle that gets run down by a big, bad cheetah on the African plains, the “poor little rabbit” chased by a bobcat. People love “underdogs”? I do not get it. Predators got to eat too, they are just doing what they were made to do. It is a fish eat fish world. I am fascinated every time I experience that predator/prey interaction in some form, whether it be watching big blue catfish eating feeder fish in an aquarium or feeling that “thunk” on the end of my line!