|
>Date: Wed, 16 Aug 2000 09:46:06 +0100
>From: Richard Lord <[log in to unmask]>
>
>I was speeding across the English Channel from Guernsey to Poole
>Harbour, UK last Friday when I saw my first oceanic sunfish, Mola mola,
>of the year gently waving its dorsal fin just north of the South bound
>shipping lane. A few compass jellyfish, Chrysaora hysoscella, have
>washed up on Guernsey beaches during the last month. I do not know if
>the Mola mola schools follow concentrations of these jellyfish up the
>English Channel.
>
>I am curious as to how a weak swimmer such as the Mola mola swims into
>northern latitudes during the latter part of the summer and then
>presumably retreats south with the onset of colder weather. Does the
>oceanic sunfish undergo vertical migrations to use ocean current
>transport? Has someone on this list studied the migrations of Mola
>mola? Does anyone know the temperature tolerances of Mola mola? I have
>seen large schools of Mola mola off New York, USA during the summer
>months. Where do the schools of Mola mola from the Eastern and Western
>Atlantic go during the winter months? Do these fish go south for the
>winter? Thank you for any insights.
>
>><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><>
>
>Date: Wed, 16 Aug 2000 15:52:24 SAST-2
>From: "PROCHAZKA, KIM" <[log in to unmask]>
>
>I know nothing about the habits of ocean sunfish, but I was in the UK
>recently, and saw one at Trevose Head in northern Cornwall on 6
>August - thought you may be interested in the record.
>
>It was lying on its side, flapping its pectoral fin and drifting in a
>strong tidal current. After a while it disappeared under the cliff.
>There seems to be some confusion about whether or not these things
>are in difficulty when they are lying on their side, or whether they
>are just soaking up the sun. We waited for quite a while and it did
>not reappear from below the cliff, leaving the impression that it
>had, indeed, been washed up on the shore. Does anyone have any more
>intimate knowedge of these fish?
I've been recording sightings of Mola mola made from aerial surveys for
marine mammals off the U.S. east coast since the late 1970's. The total
number of records is now approaching 4,000, and there are likely tens of
thousands of them in U.S. Atlantic waters. Unfortunately, except for a few
of us biologists of questionable sanity who find them to be fascinating
creatures, there seems to be little interest in research (or, more
importantly, in funding the research). I did manage to get one paper on
distribution and abundance into a sea turtle symposium by suggesting that
they could be significant competitors with leatherbacks (Preliminary
assessment of competition for prey between leatherback sea turtles and ocean
sunfish in northeast shelf waters. Pp. 144-147 in: J.A. Keinath, D.E.
Barnard, J.A. Musick, and B.A. Bell, eds. Proceedings of the Fifteenth
Annual Symposium on Sea Turtle Biology and Conservation. NOAA Technical
Memorandum NMFS-SEFSC-387, National Marine Fisheries Service, Miami, FL. 1996.).
Off the northeast U.S., they are most abundant in late summer, and largely
disappear in the winter, but where they go is an open question. Our
sightings off Georgia and Florida are between November and April, but that
pattern is entirely due to the timing of the surveys (targeted at right
whales in their winter calving ground). So I can't say from our data what
their occurrence during the rest of the year in the Southeast might be.
Molas may not entirely be the weak swimmers that they appear to be. We have
seen them make large splashes at the surface that look like breaching whales
from a distance. Furthermore, I've always presumed that their habit of
lying on one side was normal behavior. I would guess that a majority of the
sightings are of animals in that orientation, since one that is vertical in
the water would be much less visible to an observer in a passing aircraft.
Cheers,
Bob
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
| Robert D. Kenney, Ph.D. www.gso.uri.edu/faculty/kenney.html |
| University of Rhode Island [log in to unmask] |
| Graduate School of Oceanography |
| Bay Campus - Box 41 TEL: (401) 874-6664 |
| Narragansett, RI 02882-1197, U.S.A. FAX: (401) 874-6497 |
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-==-=--=-=-=-=-=-=-=-=-=
| "But why would people so woefully lacking in the basic facts of an |
| issue think they were the best informed? Social scientists call the |
| phenomenon 'pseudo-certainty.' I call it 'being a f***ing moron.'" |
| (Franken, Al. 1996. Rush Limbaugh Is A Big Fat Idiot. Delacorte |
| Press, New York, NY. p. 12.) |
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><>
To leave the Fish-Sci list, Send blank message to:
mailto:[log in to unmask]
Vacation? send SET FISH-SCI NOMAIL to [log in to unmask]
><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><>
|
