NANFA-- RE: Fundulus similus

B.G. Granier (bgkajun_at_worldnet.att.net)
Wed, 4 Dec 2002 13:41:24 -0600

Thanks for your note to the NANFA e-mail list Andy!

I don't know if I've ever sent this to the NANFA list, but back around 1996 or
so, my son and I went fishing in the salt/brackish water near Port Fourchon,
Louisiana and while we stopped at the boat launch to maybe catch some F.
grandis (Cocahoe minnows in the local jargon) with my cast net........

I noticed a congregation of about 100 topminnows all swimming up into the very
shallow, high-tide covered, shell and sand debris. As I watched them display
the typical Fundulus spawning behavior, ie: arched bodies, males embracing the
females and leaving a swirl of sand as they deposited one egg.......I realized
that the coloration on the males was something I'd never seen before!

I thought I'd discovered a new species! After I composed myself and retrieved
my net from our truck, I found that the Fundulus were actually Fundulus
similus....but with a big difference from the usual coloration that I would
normally expect!

The males had a cream-colored body with green highlights on the fins and were
quite spectactular in their spawning coloration! After closer inspection, I
realized that they were in fact Fundulus similus and not some new species....

The time of day and the phase of the moon, ie: high tide at a full moon phase
had drawn them up into the extreme shallows to deposit their eggs which would
probably hatch in accordance with the next high tide in coincidence with the
next high tide of the month.........this is strictly speculation and not
scientific fact you see. But, given that most Fundulus eggs have a 14-17 day
incubation period, it makes sense to me. It was about 12 noon which was the
forecasted time of high-tide, when we observed this frenzied spawning
activity.

This was the first full moon of May, something like May 5th if I remember
correctly.

Regards,

BG
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