Hybrid Sunfish?

This sunfish is from the White River drainage in AR. I see Bluegill x Green. What do you guys think? Centrarchid?

Edited by IsaacSzabo, 27 August 2012 - 09:23 AM.

I see a green. I see what you are seeing, but think it is just a variation. Greengills have a much deeper body. But don't take my rookie word for it. I have Greengills in my pond and they are very different.

I see green only as well. Hybrid with bluegill tends to have smaller mouth (although mouth size in pure green is variable) and lower operulum has the blue area like with bluegill. The electic-blue stripes on operculum are a bit broad but I have seen that before.

Interesting. I guess it could just be an atypical green. I certainly respect your experience in this area. Perhaps I just have not been exposed to greens that look like this before. Here's a comparison with a typical green from the same spot:




Several things stand out to me as different from a typical green:

1. Mouth extends to just the front of the eye versus close to the center of the eye.
2. Pronounced depression on nape versus straight nape.
3. Body depth greatest near the pelvic fin insertion and tapering significantly versus body depth tapering more gradually.
4. Pectoral fins appear to be slightly longer and more pointed versus shorter and rounded (from looking at higher resolution photos).
5. Blue spots/spangles on side forming loose vertical bars versus blue spots forming loose horizontal rows; vertical bars (when present) composed of dark pigment.
6. As Centrarchid mentioned, broad operculum stripes versus narrow operculum stripes.

Can these differences be explained by variation within the Green Sunfish species? Or by factors like sex, age, or environmental conditions? What about a hybrid with a different species? Longear, Redear, and Spotted were also present.

Edited by IsaacSzabo, 27 August 2012 - 12:56 PM.

I would look at the fusiforme shape. No other sunfish that a green would hybridize with would keep that shape. The shape alone makes it a green by default. Local variation, and you heard it from Centrarchid. Reckon it is gospel, unless Brian Zimmerman wants to contest it.

It's the tail of the fish that really strikes me as odd. I always think of Greens as "cuties" because of their somewhat stubbier, rounded tails with wide colored margins and staying nearly as opaque as the fish itself. Also, has anyone seen a Green with a head "bump" like that guy? Isaac, could you please inform me what other species are present in this river, and how big this fellow was?

I'm not gospel.

I have made crosses involving greens with bluegill, longear, redspotted and warmouth. Only the F1's were looked at. The warmouth hybrid does conserve the typical green sunfish shape while the others do not. Shape of fish in question does not look to me to be typical of F1 crosses involving bluegill, longear and redspotted and color is not right for the warmouth hybrid. What is not being considered is a back cross of one of the F1 hybrids back into green sunfish. That would yeild an animal that is 3/4's green sunfish which might be more greensunfish like in shape. Males of the F1 green sunfish x bluegill are fertile. Others F1's I played with do not appear to have been fertile even though they nested and female not given a choice would spawn with them.

Good point Matt, and you're right, Centrarchid is very knowledgeable on this issue.

Orangespotted, the tail seems a little big for a green to me as well, and the head bump is another thing that doesn't seem to fit. The fish was around 6-7 inches long. Besides Greens and Bluegills, there were also Longears, Redears, and Spotteds.

You could certainly be right Centrarchid. A back cross could explain it. Have you ever seen a green x redear cross? The opercular tab has a little red, and vertical bands on the side kind of remind me of a redear.

I have made redear hybrids with greens a few years back and let them grow to advanced size, some approaching 2 lbs if they were in good weight. They had truely red ear tabs that were not enlarged like fish in question exhibits. Presently we have some about one pound in pond with purpose of making tri-hybrids with bluegill. No offspring detected so far. Most such hybrids of such appear sterile even though nesting behavior was evident as of a month or so ago.

How common is the backcrosses out in the wild?

I agreed with others: it's a hybrid...just not a F1 hybrid.

I have no idea. F2 hybrids are produced in impoundments stocked with F1 hybrid green sunfish x bluegill. F2's are all over the place with respect to appearance; some look green sunfish like, some look bluegillish, some a more varied range of integrades, and some look outside normal range for either parental species. F2's seem to have very very low fertility. I used to work with hybrids in pond setting and tried to propogate from F1's and F2's. Critter in question could be backcross into green or F2.