RE: NANFA-L-- Blue catfish

Johnson, Daniel (DanJohnson-in-chevron.com)
Mon, 7 Aug 2006 09:43:38 -0500

I went back to the Brazos yesterday, with one of the main objectives to
look at the Ictalurus and see if I could find more blues and distinguish
them from Channels. I found six more blues along with a dozen channels.
The field mark that's standing out most to me is the shape of the back.
The blues have have an 150 degree angle at the dorsal fin origin.
Channels have a smoother back. The anal fin is also distinctive,
however, it often needs to be stretched out to to see it. You can see
the differences in Channels and Blues here:

http://www.io.com/~danjohns/fish/blue_catfish.html
http://www.io.com/~danjohns/fish/channel_catfish.html

--Dan

-----Original Message-----
From: owner-nanfa-l-in-nanfa.org [owner-nanfa-l-in-nanfa.org] On Behalf
Of SHasloue-in-kdhe.state.ks.us
Sent: Monday, August 07, 2006 8:23 AM
To: nanfa-l-in-nanfa.org
Subject: Re: NANFA-L-- Blue catfish

About the only thing certain that I've observed about color is that Blue
cats "never" have spots, whereas channel cats sometimes do.

The best character for me is the "ruler straight" margin of the anal fin
on blues. Channels usually have a pronounced roundness to the anal fin
margin.
______________________________________
Steve Haslouer
Topeka, KS

Dan wrote:

Today I collected and photographed a small blue catfish. It looks very
similar to the channel catfish of this size. I'm now thinking I've been
calling all these small yellowish cats channel cats where if I were to
look more closely, some would be blue cats. I was under the impression
that blues would be darker than channel cats at this size. Any opinions
from someone very familiar with this species?

http://www.io.com/~danjohns/fish/blue_catfish2.html

Thanks in advance.

--Dan
/-----------------------------------------------------------------------
/ This is the discussion list of the North American Native Fishes /
Association (NANFA). Comments made on this list do not necessarily /
reflect the beliefs or goals of NANFA. For more information about NANFA,
/ visit http://www.nanfa.org Please make sure all posts to nanfa-l are /
consistent with the guidelines as per /
http://www.nanfa.org/guidelines.shtml To subscribe, unsubscribe, or get
/ help, visit the NANFA email list home page and archive at /
http://www.nanfa.org/email.shtml
/-----------------------------------------------------------------------
/ This is the discussion list of the North American Native Fishes
/ Association (NANFA). Comments made on this list do not necessarily
/ reflect the beliefs or goals of NANFA. For more information about NANFA,
/ visit http://www.nanfa.org Please make sure all posts to nanfa-l are
/ consistent with the guidelines as per
/ http://www.nanfa.org/guidelines.shtml To subscribe, unsubscribe, or get
/ help, visit the NANFA email list home page and archive at
/ http://www.nanfa.org/email.shtml