Coral Spawning in Jamaica

[Robert Murray]

CORAL SPAWNING IN JAMAICA

On the north coast of Jamaica a series of dives have been made from the
Discovery Bay Marine Lab. (077.2W, 18.3N) over the last three months to
observe coral spawning. Dairy Bull reef site is well stocked with Montastrea
spp. (among other species) and is approximately a mile east of the lab. Here
is what we found;

AUGUST 14th: (7th night after full moon) at Dairy Bull, some slight spawning
by Montastrea annularis and M. faveolata was observed. M. cavernosa was also
apparently seen spawning. Observations on the same night at Mooring 1
(directly north of the lab.) only extended to spawning of errant
polychaetes. Observations were not made the previous night and no spawning
was seen the following night.

SEPTEMBER 12th: (6th night after full moon) M. annularis was recorded
spawning extensively at Dairy Bull, between 9:40pm and 10:10pm
(approximately 3.5 hrs. after sunset which was at 18:14). No spawning was
observed the previous night but the following night an equally impressive
spawning event was recorded for the normally cryptic Ophiomyxa flaccida at
about the same time (but no coral spawning).

OCTOBER 11th: (5th night after full moon) A major spawning event for M.
annularis was recorded at Dairy Bull, between 9:35pm and 10:05pm
(approximately 4 hrs. after sunset which was at 17:49). Although an
estimated 70% of M. annularis colonies were bleached (at least in part) by
this time, NONE of these were seen to spawn along with the "healthy"
colonies. The previous night no spawning was observed. The following night
no spawning was observed except for 1 tiny, partially bleached, colony of M.
annularis which seemed to be unenthusiastic and the polyps poorly
co-ordinated in their egg release.

Oct. may have shown the most important event this year in Jamaica (of those
witnessed over the season) and earlier in terms of days after the full moon
than expected.

Regards to all,

Robert Murray.


================================
ROBERT MURRAY  BSc (Hons.), FGA,
Discovery Bay Marine Laboratory,
PO Box 35, Discovery Bay,
Jamaica, West Indies.

rmurray at dbml.org
rmurray at infochan.com
rmurray at uwimona.edu.jm
T. (876) 973 2946 / 2947
F. (876) 973 3091
================================