By Darla White
I just wanted to share
some observations about the bleaching event at Olowalu, especially one colony
that we have been calling 'big mama'. This colony is 8.3 meters in total
diameter (27' edge to edge). It has lost more than 90% of its live tissue
in the last two months due to the bleaching event. What polyps that are
still there are still bleached and sickly looking.
Olowalu was hit very
hard. The sediment in most areas we observed is settling thickly in the algae
that has newly overgrown parts or all of colonies, with little hope for
recovery in the near term. One Scripps Institution of Oceanography mosaic site
did not appear to have a sedimentation issue and had plenty of Crustose
Coralline Algae (CCA), so
time will tell but it likely has a better chance for resilience. Both the NOAA
bleaching survey folks and the XL Catlin Seaview Survey team commented on Olowalu and
how bad it was this past week, with some areas still exhibiting 50% bleaching. The
newly dead colonies have a thick covering of limu (algae), but you can still
feel and even see the newly dead corals underneath the fuzz mats. I wish we had
been able to finish the baseline survey in the shallows at Olowalu before the bleaching
event. Alas, all we have is the aftermath. The Porites spp. were hit the
hardest.
There is still active
bleaching, but definitely active recovery, too. Corals are regaining their
color in part, many from the base upward or on the sides, with the worst
affected areas mostly on the upward facing surfaces. New algal growth
by-in-large dominated on the upward facing surfaces of most colonies observed,
especially Pocillopora.
Some color morphs did really well and were mostly
resistant to the bleaching, including the rust-colored Montipora patula,
and both the mustard and taupe color morphs of Porites lobata, and the taupe P. compressa.
Darla J
White
Special
Projects Coordinator
Hawai'i
DLNR Division of Aquatic Resources, Maui
130
Mahalani Street, Wailuku HI 96793
Eyes of
the Reef
Island
Coordinator, Maui
808-281-4916
Darla White on a recent survey of coral bleaching at Molokini crater, Maui. Photo by Liz Foote. |
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