Dear Conch-lers,
 
As some of you might remember, I used to submit observations of the mollusks
and other inverts in my in-law's cold sw aquarium. Now that I have one of my
own, I suppose I am going to start up again.
 
I am keeping an updated list and photo gallery of the aquarium at
http://www.ofseaandshore.com, so anyone interested in seeing the "cast" as
it were can look there. There are not many photos yet, but am adding as I
get them.
 
One unusual observation is that my Cryptochiton stelleri (gumboot chiton) is
feeding on a piece of king salmon. I know there are carnivorous chitons
(certain Mopallidae, to name a few), but never suspected the ole gumboots.
There is a good variety of algaes in the tank, and it has been feeding on
them as well (so it's not eating salmon out of desperation.)
 
The few other mollusks in the aquarium aren't doing anything particularily
interesting. One of my large prawns (Pandalus hypsinotus) found an echiuran
spoonworm buried in the sediment and extracted it very meticulously by the
worm's "spoon" and in such a way to suggest it "knew what it was doing" to
not break the worm. Interesting little battle.
 
I have been reading the current thread on exotics found in Florida & such. I
myself, as a child, found Babylonia in front of a hotel on Sanibel Island,
obviously salted.
 
I have a mystery from SE Alaska. In summer of 1997 I went on a canoe/camping
to the north end of Berner's bay (about eight miles north of the end of
Juneau's road system, and about 45 miles north of Juneau itself). At low
(-4.1) tide I went searching through a "windrow" of Saxidomus shells which
had been eaten by otters. I was looking for some good examples that showed
the characteristic bite marks from the otter's canines. In the pile were
other bivalves as well, some of which were worth keeping (like a really nice
Panomya, completely undamaged). Then I saw a large pearly disk in the pile.
I picked it up and immediately recognized it as the ventral portion and part
of the body whorl of a large Astraea. Most of the outside layer had been
worn away, leaving just the heavily eroded and bored (by Clione sponges)
pearly layer. The disk was a little over 4.5" across! This is mysterious. My
first thought was a lost, and giant, Astraea gibberosa. But gibberosa rarely
exceeds 3" across the ventral diameter. Also, I compared the piece to the
Astraea that Tom keeps at OSAS museum, and found that it closely matched
Astraea undosa in size and shape. The problem is, of course, that A. undosa
doesn't occur (and geologically never has) north of California. Astraea
gibberosa doesn't even occur here (supposing it was a giant mutant of that
species) because we are quite north of its range in Juneau.
 
Any theories? My belief, however unlikely, is that someone put it there. Why
someone would plant an A. undosa out in the middle of a deserted bay miles
from the nearest human habitation, I don't know. But that's the only
possible scenario I can envision. Maybe a beach worn souveneir from
California tossed off of a visiting fishing boat. Anyway, the specimen is at
Of Sea & Shore museum (I gave it to Tom Rice) if anyone wants any more
details on it. I think I've drivelled on enough.... Take care- Aaron
 
Aaron Baldwin
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