http://www.tpwd.state.tx.us/landwater/water/aquaticspecies/inland.phtml
To further complicate things. you may note that native folk of the lower
Brazos river area are
likely to refer to both as "Blue Channels Cats."
According to TP&W, only the Rio Grande Blues have spots on the back and
sides.
I hope this helps.
Jim
----- Original Message -----
From: "Johnson, Daniel (DanJohnson)" <DanJohnson-in-chevron.com>
To: <nanfa-l-in-nanfa.org>
Sent: Monday, August 07, 2006 10:43 AM
Subject: RE: NANFA-L-- Blue catfish
>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
/-----------------------------------------------------------------------
/ 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