12 April 2022

Heatwave

Danielle and Hollie discussed that with the decline in bleaching score of the heatwave colonies and the response in photosynthesis and respiration in the fourth timepoint that we could start to decline in the heatwave exposure since we are confident we are beginning to see a stress response and accumulated stress will be present over the next week.

Danielle started the twelfth day of the heatwave period and the beginning of the decline for the corals to to experience a diel fluctuation in the heated treatement of 29.4 °C to 30.1 °C. Through our heatwave analyses, the climatological data shows that in Mo’orea at our site in the backreef, temperatures above 29.6 °C longer than a five day period is considered a heatwave.

Daily measurements

Danielle recorded bleaching score and survivorship for the fragments and colonies and completed a daily measurements of light, temperature, salinity and pH. She also cleaned the tanks.

Bleaching score processing

Following Emma Strands Bleaching Score Protocol Emma, Hollie, Kristen, and Danielle have started processing the daily colony photos to track when the ambient and hot colonies start to differ in bleaching score. They have been updating the Photographic Bleaching Script often to make these comparisons and consult on moving forward.

It appears that the bleaching score in the colonies experiencing the heat stress have continued to decline. We see a significant difference in the interaction between treatment and day.

Data tracking

All daily measurements, bleaching score, and survivorship tracking for the colonies and fragments can be found on the Heatwave Google Drive and Gametogenesis GitHub.