Journal Articles of Relevance

Bassim, K.M. Sammarco, P.W. Snell, T.L. 2002. Effects of temperature on success of (self and non-self) fertilization and embryogenesis is Diploria strigosa (Cnidaria, Scleractinia). Marine Biology 140:479-488.

-The authors of this study wanted to find out the effects that elevated sea water temperature has on both sexual and asexual fertilization and embryogenesis of scleractinian corals. They wanted to know what level of development the higher temperatures effected and how this in part determined their success over generations.
-Earlier research suggested that optimum temperatures for coral development range from 25 to 29 degrees Celsius. Most tropical corals live at the upper level of this. There have been increasing temperatures of coral waters and the bleaching of many reefs due to high temperatures over a long period of time. This puts stress on the zooxanthellae and their coral hosts. But the information on the effect on the particular stage of development has not been significantly researched.
-The procedure used collections of egg and sperm bundles from different colonies during the spawning season. These colonies were randomly placed in 3 different water baths of 30, 31, and 32 degrees Celsius for self fertilization and another 3 baths for cross fertilization and the 6 baths were replicated again. Levels of development were monitored and examined. The results found that there was no significant difference in fertilization success across the samples but embryonic development in the 31 and 32 degree baths showed significant differences on the fourth and higher cleavage stages.
-temperature does have an impact on the development of coral in the higher cleavage stages of embryogenesis. This surprisingly has no effect of the fertilization process. As the time increased at the higher water temperature there was a significant increase in the time of development to the next embryonic stage even at just a temperature change of 1 degree Celsius. With a decrease in the production of healthy larvae we may witness a decrease in the success and abundance of corals in the future.