Pelagic fishes - A Fascination for Fish: Adventures of an Underwater Pioneer - page 273

evolutionary upstarts that hadn't yet been around long enough to de-
serve her respect. That first mola, however, intrigued her. After all, an-
other creature that liked jellies couldn't be all that bad.
Together John Christiansen and Freya took on the challenge of car-
ing for our new mola. Freya's extra jelly supply quickly ran out, so they
tried feeding the mola small pieces of shelled fresh shrimp attached to
a clip on the end of a pole. The fish loved it. Within a day it learned
to associate the white plastic pole with food and would hurry over as
soon as it spotted it. In spite of all the competition for food in that ex-
hibit, the mola was doing very well.
After a few weeks, however, the temperature in the Bay dropped to
fifty-three degrees. The mola stopped feeding and became disoriented.
Sadly, we had just discovered the lower temperature threshold of mo-
las. Because we had no way of heating that exhibit, the mola died.
We had learned an important lesson, though: if we wanted to con-
tinue research with molas, we had to have a temperature-controlled
environment. We therefore installed a gas-fired pool heater, a recircu-
lating pump, and a sand filter on a twenty-foot-diameter tank in the
quarantine room. To accommodate the vertical nature of molas, we
raised the height of the tank from four to six feet. We were now ready
to try again.
Molas were still around, and John Christiansen and Freya collected
four more molas for the new temperature-controlled tank. They found
that the molas transported better when they were placed head down
in a large plastic trash bucket; with no room to move, the fish couldn't
damage the tips of their long fins. The trip in the bucket was quite
short, and they were back at the aquarium within thirty minutes. Freya
and John also designed a special stretcher for moving the oddly shaped
molas from the boat to their new home.
One of the four new molas died within the first few weeks, and an
autopsy showed it was loaded with internal parasites—large tapeworms
in the intestines and nematode roundworms throughout the muscles—
which, together with the stress of being collected and the strange en-
vironment, had caused it to decline and die.
We knew that molas are notorious for being heavily parasitized, and
we decided to try to rid them of these unwanted hitchhikers. Their