Sad news from Chuuk – Micronesia

© Till Rothig

8 February 2017

In Chuuk, Tara scientists found considerable coral mortality and ongoing bleaching. Reports indicate conditions may be even worse in Guam.

With little published data before 2016 on the conditions of Chuuk’s coral reefs, the Tara team had hoped to find conditions better here than the high coral mortality they witnessed in Tuvalu and Kiribati.

Scientist Till Röthig from King Abdullah University of Science and Technology (KAUST) located in Thuwal, Saudi Arabia, noted, “I was surprised to see corals as deep at 30 meters impacted by bleaching.” He describes visual evidence that suggests the bleaching has been going on for some time, “A colony of massive coral was partially dead on top, with algae growing on it, then further down the coral tissue was alive but bleached. At the bottom, the coral tissue still seemed healthy”.


Le Scientifique Till Rothig examine la proue incrustée de corail sur l'épave du Fujikawa Maru, vieille de 73 ans
Tara Scientist Till Rothig surveys the coral encrusted bow of the 73 year old Fujikawa Maru shipwreck © Pete West / BioQuest Studios


People in the Chuuk government state there was no temperature related bleaching before 2016, and this is supported by data from the NOAA coral watch site. NOAA data reaching back to 2000 indicates no major temperature anomalies before September of 2016. Then, the temperature increased for a three-month period, likely causing widespread coral bleaching and mortality in the region. What Tara scientists witnessed seems to be the aftermath of this acute bleaching event.

Tara will next examine Guam’s coral, following a 3-day, 580 nautical mile voyage. Tara is currently sailing under (Beaufort scale) force 6 winds, under partially cloudy skies, and facing 3 meters of swell. Everyone is learning how to live and work in very rocky conditions, but spirits are still high.


bleached anemone
An anemone – a close relative of reef corals – that appears translucent because it has lost its colorful algal symbionts: it has bleached © Till Rothig


Located right outside of the “coral triangle”, Guam is historically known for having an incredibly diverse coral ecosystem. However, The Washington Post recently quoted Laurie Raymundo, Coral Ecologist at the University of Guam: “For the past four years (2014-2016) we’ve had bleaching episodes, and we have not had them to this extent in recent history.” Describing her recent shock after dive to view the coral, she posted on Facebook, “I consider myself to be fairly objective and logical about science but sometimes that approach fails me. Today, for the first time in 50 years I’ve been in the water, I cried for an hour, right into my mask, as I witnessed the extent to which our lovely Tumon Bay corals were bleached and dying”.

Sarah Fretwell

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