[Coral-List] Benthic cover on mesophotic reefs

[Pawlik, Joseph]

Greetings!

You may be interested in the article listed below that compares survey techniques for estimating benthic cover on reefs in the mesophotic zone. In it, we refute a recent claim that benthic cover data taken from photo-quadrats (common to many ROV, AUV and submersible studies) is seriously flawed because of image distortion, and can only be used qualitatively. We compare the merits of benthic cover surveys conducted using technical diving versus underwater vehicles within the context of testing the sponge increase hypothesis on Caribbean mesophotic reefs. We also try to explain the highly divergent estimates of sponge cover that have been reported using these two different methods (~80% vs 10%, respectively) at the deepest survey depth for tech diving (91 m), which is only half-way through the mesophotic zone.

Pawlik, J.R., Armstrong, R.A., Farrington, S., Reed, J. Rivero-Calle, S., Singh, H., Walker, B.K., White, J. 2022. Comparison of recent survey techniques for estimating benthic cover on Caribbean mesophotic reefs. Marine Ecology Progress Series, 686: 201-211
https://www.int-res.com/articles/meps_oa/m686p201.pdf
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A YouTube video that shows sponge cover (along with other benthic cover) over the full span of the mesophotic zone along several ROV tracks in Puerto Rico and from a submersible in Roatan, Honduras, can be found at this link:
https://youtu.be/NSkN0NkJwc0

Recent data on benthic cover of corals, sponges and macroalgae from Puerto Rico, St. Thomas (USVI) and Flower Garden Banks (Gulf of Mexico) from mesophotic reefs derived from ROV photo-quadrats can be found here:
Scott, A.R., Battista, T.A., Blum, J.E., Noren, L.N., Pawlik, J.R. 2019.  Patterns of benthic cover with depth on Caribbean mesophotic reefs. Coral Reefs, 38: 961-972.
http://people.uncw.edu/pawlikj/2019CoralReefsScott.pdf

Regards,

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Joseph R. Pawlik
Frank Hawkins Kenan Distinguished Professor of Marine Biology
Dept. of Biology and Marine Biology
UNCW Center for Marine Science
5600 Marvin K Moss Lane
Wilmington, NC  28409
Office:(910)962-2377; Cell:(910)232-3579
Website: http://people.uncw.edu/pawlikj/index.html
PDFs: http://people.uncw.edu/pawlikj/pubs2.html
Video Channel: https://www.youtube.com/user/skndiver011
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