A
well-rested team was raring to go to complete our experimental design
activities for the day. After a torrential downpour, Team Drone went out to
determine at what height the drone could best be used to obtain footage of the
land or sea below it, and what area one frame of drone footage would record.
Jose Huerta, our preferred drone operator, tested out different heights and
found that 25 ft (7.7 m) would be an ideal height above ground (or water), and
the team scurried around according to his instructions and placed some of our
food cans at the corners of the field of view. They then proceeded to use
Amanda Callahan’s tape measure to determine the length and width of the
recorded area—and repeated the process several times in order to be able to
calculate the potential measurement error!
With
these data recorded, we went to the outer side of the island at the boat pier
to look for elkhorn corals. The lagoon side tends to be the calmer side of an
atoll, with a different diversity of sea life than the ocean side. We were
hoping to confirm the existence of Pacific Elkhorn Corals, a species considered
fairly rare and only reported from the Marshall Islands in 2010 by Dr. Zoe
Richards from Australia (see http://www.livescience.com/8415-rare-coral-discovered-pacific-ocean.html). We contacted Dr. Richards to ask whether she would be
willing to share the position of her elkhorn coral patch with us so that we
might be able to determine their status and test whether use of a drone might
allow the identification of additional elkhorn colonies. Thus, while some of us
went to snorkel out to the location, Team Drone tested out how to fly a
transect and a search pattern across the coral fingers that fringe the ocean
side of Arno Atoll.
I am
happy to report that we were successful in locating two elkhorn coral sites,
and that it does appear as if an aerial view could help with a preliminary
identification of where additional sites might be located. Our drone footage
showed a specific color for the elkhorn corals, slightly different than those
of other coral colonies. Of course, this information is very preliminary, but
in a day and age when coral bleaching and invasive sea stars are eroding the
health of coral reefs, any form of speedy reconnaissance may be helpful to
facilitate coral research. On Arno, we fortunately found no evidence of coral
bleaching or invasive crown-of-thorn sea stars.
We spent
our last evening discussing some of our findings, both those related to corals
as well as those related to lizards. It appears that both lines of experimental
design may allow us to write up our results as brief publications! I love it
when a good thing comes to fruition, and it shows my students both how science
works and how rewarding it can be to gain scientific knowledge.
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Figuring out the way Marlin, our quadcopter drone (in the foreground), takes images. Ruby Resendez, Amanda Callahan, and Dakota Brooks (from left) are measuring the field of view.
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Taking scientific measurements takes some doing. Fortunately, these students were trained in General Biology technique at Victor Valley College, where measurements form part of the curriculum! From left: Dakota Brooks, Amanda Callahan, Ruby Resendez, Mitzia Zambada.
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Amanda is all smiles during the snorkel for corals. Well, at least all thumbs up! Photo courtesy of Morgan Lewis.
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The object of our search, the rare Pacific Elkhorn coral (Acropora rotumana). In the expanse of this particular reef, we were only able to locate two Elkhorn colonies. We are happy to report that the corals are doing well around Arno, with no coral bleaching to be seen, and no crown-of-thorn sea stars around. Photo courtesy of Morgan Lewis.
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