Re: NANFA-- How fish get from A to B

Shireen Gonzaga (whimbrel_at_home.com)
Tue, 14 Dec 1999 18:56:31 -0500

Jay DeLong wrote:

> Baltimore-stomping Gonzilla asked:

Careful, Steelhead or Steelbrain (or whatever that salmon
is called) ...the Capitol Lake Monster, a good friend of mine,
_watches_ you while you're out there walking Oliver, and
one of these days...

> Possibly the medium the eggs were layed on is what's being transferred, and
> not just the eggs themselves. I can't believe birds can accomplish such an
> amazing feat on their feet in the numbers you refer to. Don't these killies
> lay their eggs in submerged grass beds?

Exactly! The eggs adhere to vegetation, right? A wading bird stalking
fish could easily get some of that vegetation tangled around its feet,
then fly off to another nearby pond with the veges still tangled around
its feet. If it's a short flight, the green stuff remains moist and the eggs
still viable. Herons and egrets are big birds, they probably don't mind
a few strands of plant matter around their feet.

> Perhaps mammals like muskrats are
> doing this as they swim through the grass beds and scamper across the tide
> flats and into the freshly flooded freshwater ponds draped with garlands of
> stowaway plants and killie eggs.

Again, yes! Excellent point. We have muskrat and nutria there. Sometimes
we're lucky and get otters too.

> Also, are the dikes free of muskrat
> burrows? That may be a way for the fish to get into the ponds, too. That
> animal is the bane of earthen dams everywhere. I realize you'd possibly see
> some water in the ponds during the dry season if this was the case, but
> maybe muskrat movements and burrowing activities coincide with the wet
> season.

The dikes are pretty thick, and I doubt if an enterprising muskrat
could burrow from one impoundment to another.

> It would be most interesting to know if there are both juvenile and adult
> killies present in the ponds. I think from what you said, they were adult
> fish. If they are hatching from eggs, there would be a lag time before you
> saw any adult fish. If adults are appearing immediately after these storm
> events, then adults are getting in somehow. Could these storms produce
> winds strong enough to hurl fish and/or egg-laden plants short distances
> through the air?

There was certainly a lag time, perhaps a couple of months. The fish
were adult. I think this all happened last year, or maybe this year, I'll
have to check my notes. It was dry at the beginning of the birding
season. Then we got some rain. I believe I returned in the early summer
when the water was back in the impoundments and saw a Forsters Tern
fishing. Good luck, buddy, I muttered. Then the little fella caught a fish
and my jaw dropped!

For the one particular impoundment where I observed the fish, most of it
is surrounded by trees so wind-blown plants probably could not get from a
fw pond to the inpoundment. But it could have come from the salt marsh
opposite the impoundment--maybe those fish were spotfin killies and
mummichogs, both of which are abundant in the refuge bay area and
can tolerate freshwater.

I'm gonna take all these cool ideas and go bug the refuge biologist with
it ...poor fella, I'm such a pest...

thanks!

- shireen

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