Re: NANFA-- Strange Bullhead Behavior - An explanation?

Roselawn Museum (
Wed, 10 Jul 2002 11:24:47 -0400

Hi Rob

I've been keeping a large yellow bullhead for about three years now. I feed
him almost exclusively golden shiners from the bait shop. I generally have
about two dozen in with him at any given time. As bullheads do, he mostly
hunts them at night, and at rare moments will take one in the daytime if it
swims too close to his mouth. This seems to be a rarther lethargic exercise
in feeding. However, if I drop live gambusia in with him (at any time of
the day), he goes beserk, similar to what you described. He will literally
gorge himself until all the gambusia are gone. Hope this helps.

Steven A. Ellis
Kennesaw, GA

At 10:08 AM 7/10/02 -0500, you wrote:
>-Tried sending this yesterday but it didn't seem to go through...
>Today, I had some leftover bait shop shiners ("crappie minnows") from a
>fishing program. As I usually do, I added these to the Nature Center's 100
>gallon community tank for the enjoyment of the resident warmouth,
longears, et
>al. Normally, this results in a typical little feeding frenzy but today, two
>3-4 inch long black bullheads each grabbed a shiner that looked to be
>maximum size for swallowing. Immediately after engulfing the shiners, both
>the bullheads began writhing uncontrollably, swimming irratically, spinning,
>diving, and virtually every other action that could be described as
>uncontrolled movement. Pardon the anthropormorphism but they actually
>"looked" like they didn't know what was going on. The odd behavior lasted
>about 30 seconds for each bullhead and the bullhead immediately resumed
>bullhead behaviors after the writhing stopped. Consensus among those in
>attendance (all naturalists enjoy watching a good feeding frenzy), was that
>the shiners were still alive and through their gyrations inside the
>deigestive tracts were causing the unusual external behavior. Has anyone
>seen something like this or does anyone have another, better explanation?
>Rob Denkhaus
>Fort Worth Nature Center & Refuge
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