The Yin and Yang Survival of Coral Reefs

It’s hard to imagine the life of a sailor on the wooden tall ships of days passed crossing the Pacific in search of the “great white whale”.  But we can envision the rolls of the seas splashing across the deck, the green horns spewing their guts out over the rail, and the stale and flavorless food that magically transforms into their ‘nourishment’.  Today, the seas still splash across the deck and newbies continue to wretch over the rail, but the food has improved exponentially and the time spent isolated on a ship is more on the order of a couple of weeks to months rather than several years before you reach your home port.

For the last 20 days I have been sailing on the NOAA Ship Hi’ialakai traversing the Pacific to the U.S. remote island areas. We ‘set sail’ on Sunday the 26th of March and headed south through the rough seas towards the equatorial islands of Jarvis, Baker, and Howland Islands.  All of these islands are wildlife refuges and a part of the Remote Pacific Islands National Marine Monument.  They are isolated, uninhabited, low islands that are desolate on land but enchanting underwater. Our purpose is to assess the status of these reefs given the record high sea surface temperatures recorded in the fall of 2015.  These islands were visited in the spring of 2015 and scientists found them to be healthy and productive. Jarvis Island was visited in the spring of 2016 and scientists found that nearly all of the corals had bleached. Now in the spring of 2017, we wondered, have these reefs recovered from the bleaching event?

It took us 7 days to reach Jarvis Island. The first time I visited Jarvis Island was in 2004 and my experience from that initial trip as a young budding scientist was transformative. The reefs are extremely productive due to the upwelling caused by the equatorial undercurrent that flows into the island forcing nutrient rich waters upwards into the shallows. Witnessing literally thousands upon thousands of planktivorous fish among schools of giant hammerheads, gray reef sharks, rainbow runners, and manta rays made my heart skip a beat. On top of the swirling mass of fish, the benthos was rich and colorfully diverse full of healthy and shapely corals. I was in awe.  This is the poster child for what an unimpacted healthy reef should look like. It became one of my favorite places to dive and I have been fortunate to return to Jarvis every other year thereafter through 2012.  I was not prepared for the shock that awaited me.

West side of Jarvis in 2012 (left) and in 2017 (right)

It had become clear that the coral did not survive the high sea surface temperatures for nearly all were dead.  It was if the Jabberwocky had come crashing through my wonderland.

A few days after completing our assessments at Jarvis we arrived at Baker and Howland Island. As I rolled over the small boat, heading down the water column for my first dive, I was shocked to discover an intact and productive benthos.  The devastation that plagued Jarvis did not impact Howland or Baker. So there is hope.

Reefs at Howland 2017

The ship is currently rolling considerably and waves are splashing across the upper decks.  We have 4 more days of transit until we reach the last island we plan to assess on this trip, Wake.  Fortunately, my ole sea legs are holding up quite well although, I can’t say the same for other folks on the ship as their faces turn green and they crave their bunks wishing for the motion to stop.   I sit here typing, popping popcorn like there’s no tomorrow, and glancing at the porthole on the down roll as the ocean plays peek-a-boo with me. To think, a hundred plus years ago, I’d be soaked to the brim and strapped to the rail to ensure that I don’t fall to the depths of King Neptunes’ Realm.  Glad I’m from this era.

If you’d like to follow us while we make our way through the Pacific, check out our storyboard: http://arcg.is/2nfVxcA