2015 Darwin Science Expedition - Day 5 On to the outer islands…

After a very gentle overnight trip (the weather is still a faintly rolling calm beneath the boat) we arrived at Peros Banhos Atoll shortly after sunrise. Sundowners were a treat last night with calm seas to the horizon of low puffy clouds lit red by the setting sun. This morning was equally appealing. Such light weather conditions offered a rare opportunity to get ashore at Coin du Mire.



This uplifted shelf of fossilized reef offers sheer rock for the oceanic swell to break against and as a result is off the visit list in all but the most serene seas. Although unapproachable as a regular destination for people the opposite is true for a number of bird species graced with the ability to glide over the waves crashing with full force against the rocks to land on the emerald green grass that carpets the top of the shelf. There Masked Booby and various terns make their nests.



So on this day of lovely weather we made the most of the opportunity and stepped straight off one of the small expedition dive boats onto the top of the shelf with only a gentle roll to sway us. The rock is only about 100 meters across and a few hundred meters around but is home to at least 100 nesting pairs of birds of various species. The greenery sprouting all over the central plateau comprises four species of grass and surprisingly, a healthy population of grasshoppers. How did they get to such an isolated outcrop of stone? A mystery.



The day continued with interest from there…for the remainder of the morning and into the afternoon I accompanied Courtney on snorkelling surveys around some of the lagoon knolls of southwest Peros Banhos. With water like glass we watched small fish flitting amongst the corals in water 15 meters deep. As we were snorkelling we surveyed shallower depths than this and revelled in the beautiful vistas of coral fading into blue in all directions.



Whilst doing this exploratory work we discovered a coral pinnacle jutting abruptly up from a depth of about 15 meters all the way to within a few meters of the surface. It was crawling with soft corals and alive with fish – a great discovery. Just as we were examining this we heard whistling behind us and turned to a pod of dolphin cruising by. What amazing experiences to be had in this fantastic marine protected area.


After a few more snorkel surveys that turned up a number of other fantastic coral gardens (and a turtle hiding under an acropora table) we headed down south to Ile du Coin for a dive just inside of this island. Again, coral gardens sweeping as far as the eye could see (or fin could swim) in each direction. Anne and Charles successfully recovered their temperature logger from this site…usually they’re quite difficult to find but on this occasion they practically dropped on top of it. More data to add to this large set of information on temperature fluctuations in the waters of the territory.


As if the day didn’t hold enough great experiences I’ll now be heading ashore to Ile Vache Marine for the evening to set out rat traps with Pete. There has been a trial rat eradication effort on this island in the hope that removing these invasive animals will allow the seabirds to return and nest. I’m sure there’ll be more to report on the wildlife of this island when I return to the research vessel tomorrow! (I’ve already heard that there is a turtle nesting there as I write this…better get moving!)


2015 Darwin Science Expedition