Date: Wed, 11 Sep 1996 22:33:32 -0800 (PST) From: Aileen Morse To: coral@aoml.noaa.gov Subject: RE: Coral spawning in Key Largo Hi! I was on the NOAA vessel at this site on both 9/3 and 9/4. We were netting coral heads to collect egg bundles. On 9/3 there were only egg bundles in 2 of our collecting vessels (none in any of our others, or in those put out by Prof. Alina Szmant's group). The 2 colonies that released on that night were both A. annularis. Then on 9/4 we and Alina's group both collected multiple releases from both A. annularis and A. faveolata colonies. Collections by both groups indicated that more A. annularis colonies went off than A. faveolata. But in neither case could the number of colonies releasing be considered a "major" spawn. Our aim was to fertilize large numbers of gametes from both species and also to try an inter-species cross fertilization. In this we were successful. However, both research groups observed that there was an unusually high heterogeneity in the early stages of larval development for both species (and in our cross). I cannot speak further for Alina's results, only our own. By the second day the cultures of A. faveolata became much more homogeneous with respect to developmental stage, as did the cross, and have remained so. However, the cultures of A. annularis remain highly heterogeneous and have developed much more slowly (even the most advanced stages). Although fertilization success appeared to be relatively high, development of subsequent larval stages seems to be relatively retarded. As to your question re. the white substance being released fron colonies, perhaps this was coral mucus. Corals tend to respond to "stress" by mucus release. When working with my Japanese colleagues at their lab off Okinawa colonies were placed in containers for egg bundle release. Very commonly coral mucus is seen mixed in with the bundles. Anyway that is my best guess. Best regards, Aileen Morse Aileen N.C. Morse Marine Biotechnology Center Marine Science Institute University of California Santa Barbara, CA 93106 PHONE: 805-893-4277 FAX: 805-893-8062 E-mail: a_morse@lifesci.lscf.ucsb.edu