Re: NANFA-- Interactions between Gambusia, Heterandia and

Michael Sandel (
Mon, 29 Mar 2004 19:51:58 -0800 (PST)

Hello Sajjad,
I recently finished up a collecting trip in the SE US. I can't give any tested info, but these are the general patterns I saw during this trip.
-found Gambusia and Mollies coexisting in generally high abundance and in close proximity (along with flagfish). In some places at least, they must fill noncompetitive niches. I think that Mollies in general are a group that communes readily with other species, as I have collected schools mixed with sheepshead minnows as well.
-Gambusia seemed to dominate when coexisting with Heterandia, and they did not seem to occupy the same areas in the pools (didn't school together). I did not find any place where Heterandia was the most abundant Cyprinodont. I did not find Mollies and Heterandia coexisting (again, only one week's worth of observations). Perhaps the young mollies would outcompete Heterandia for food etc.

Anyway, I kept some of each alive, and have not seen any direct aggresion, probably will work out ok in a tank setting with enough food to keep everybody happy. My mollies are only slightly bigger than female Gambusia at present, who knows what will happen when they grow.
I would not expect any of these species to interbreed. Gambusia can't breed with guppies (->Mollies) according to Dr. Axelrod.
I would hate to see a female H. formosa try to carry a Molly hybrid!


Sajjad Lateef <> wrote:
What kind of inter-species interactions can be expected from
Gambusia, Heterandia and Peocilia (mollies)?
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