Green Sunfish in NJ?

I caught these guys out of a small stream possibly called Golden Run that flows into the middle part of the Delaware river in West Trenton, Mercer County NJ. The stream did feed a small lake that was recently drained so it is possible that is was stocked with Green Sunfish since they aren't native to NJ and NJ is nowhere near their native range. I'm not doubting the members who said these are green/hybrid greens I'm actually inclined to believe them I'm just curious how they wound up in a small stream when I've never caught one before. One curious thing they did when caught was flare their gills like Rock Bass do and they are thicker bodied then most sunfish I've caught.

Possible Green Sunfish





Possible Green Sunfish/Pumpkinseed hybrid

First two are indeed Green Sunfish. The second two pictures appear to be a hybrid, probably GreenxBluegill or vice versa.

Green sunfish are the most "basslike" of the Lepomis sunfishes, with a bigger gape and more elongated, robust body. And they're certainly an adaptable species for wherever someone has the bad judgement to introduce them.

You mentioned the key reason behind their potential introduction; the stream was fed by a man made pond. Seems almost cut and dry to me. Really there are only a few ways a pioneering, tolerant fish like a green sunfish can get into a headwater stream, come from upstream (usually an impoundment), come from downstream, or come from a bucket or stringer.

Hybrid sunfish, macrochirus X cyanellus are commonly stocked in ponds for their fast growth, agression, and lower fecundity. Well they will spawn to some extent, and when hybrids breed, they play out to look like one or the other parent species. So ultimately, a population of greengills will degrade into bluegills, and green sunfish. I am certain that this accounts for some of the widespread introductions of green sunfish.