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Patagonian Fjords Expedition: Corals Like Nowhere Else on Earth

Follow along as NG Grantee Rhian Waller explores the surprisingly diverse corals that dwell deep in the fjords of the southern tip of South America, and discover what they can tell us about the rest of the ocean as well. For the last two days Dan Genter (from the Huinay Scientific Field Station), Chris Rigaud...

Follow along as NG Grantee Rhian Waller explores the surprisingly diverse corals that dwell deep in the fjords of the southern tip of South America, and discover what they can tell us about the rest of the ocean as well.

For the last two days Dan Genter (from the Huinay Scientific Field Station), Chris Rigaud and myself have been at Reñihué Fjord, the next fjord south from Comau where the majority of our work is being done. This fjord lies within Parque Pumalín, a nature sanctuary of over 700,000 acres, administrated by the Fundación Pumalín and donated by Douglas Tompkins and the Conservation Land Trust.

Loading the San Ignacio for our trip to Reñihué Fjord. Photo by Rhian Waller.


On the morning we left the weather was bad – rain and wind had pounded the station all night, and we had to cancel our morning dive. But it was under rainbows that we arrived at Leptepu Ramp – the gateway for Pumalín Park, and were met by Eduardo, who shuttled us and our mountain of gear into Reñihué. From there we loaded into a small boat and took the trip across the fjord to Casa Palema, where our rather luxurious cabin awaited, complete with fire already lit.

Rainbows over the high fjord mountains as we get closer to Parque Pumalin. Photo by Rhian Waller.


The next morning we awoke to the sound of yet more rain and wind (this is the Patagonian winter after all). With our cabin being nestled in the trees, we were unsure if we were really going to get to dive in Reñihué Fjord that day. So we donned drysuits and awaited our ride to the boat. Our caretaker Christian arrived with the tractor (a most unique dive vehicle!) and we loaded tanks and gear for the day and headed down to the waterfront, being pounded by cold rain all the way. Soon the boat with Captain Ricardo came to meet us, heavily laden with all the dive gear we had left from the day before. Willing to go to our site and take a look at the waves we headed out into the wind into Reñihué Fjord, a stunning sight even in the grey mist. Passing a handful of flamingos and pelicans dipping down in front of us, we arrived at Punta Mamurro, towards the end of the fjord, and lucked out. The waves here were not too bad, so we jumped in, eager to see the corals we’d been told about.

The tractor/truck/semi-amphibious dive vehicle. We want one of these for the University of Maine! Photo by Rhian Waller.


Fjords are generally steep sided, cut many thousands of years ago by glaciers passing through the region. This dive site to me was a typical fjord site – straight up and down, a sheer wall as you drop down, getting darker and darker as you go. At 20ft a few mussels; at 40ft a few zooanthids; at 60ft some coralline algae; at 80ft a few anemones dotted the sheer wall. And there they were, just on the border between 90 and 100ft, Desmophyllum corals, in the hundreds, but in a unique form seen nowhere else on the planet – long thin calyxes, sticking out over 10 inches from the wall.

Sticking out like tubeworms - abundant, large and healthy Desmophyllum. An amazing sight. Photo by Rhian Waller.


They almost looked like a colony of tubeworms, there were so many. Another moment in this trip where I just had to stare in awe for a moment at these deep-sea relics, before getting down to the tasks at hand – take photographs, count individuals in quadrants, collect 15 corals for reproductive analysis, deploy the logger (to measure salinity, temperature, and light). At that depth you have little time to work – 20 minutes at most. We had to go back in for a second dive to finish all the science, but it’s not a bad thing to see that sight twice.

The sheer amount of rain has made for some low visibility dive conditions. Here Chris Rigaud (forward hand) and I (hand at the back) deploy a data logger. I'll pick these up next year to download their valuable environmental data. Photo by Dan Genter.


The trip to Reñihué and Pumalín Park was a huge success, despite somewhat nasty weather. I managed to get samples of these corals from a different fjord ecosystem, healthy and thriving, to compare to Comau. However, yet again this trip I am also a little saddened. The salmon farms prevalent in Comau have reached Reñihué Fjord, and their impact could be seen at one of our dive sites – a thick ‘sludge’ layer covering the bottom; corals dead and dying covered in an organic mat; and masses of urchins, thriving on the excess food and nutrients being pumped into the system. Unique to this region I have to wonder if I’ll ever be able to say, “that population is pristine,” just as it was when this species first colonized the fjords.


Processing samples at Casa Palema, Parque Pumalin. These samples will be sent back to my laboratory at the Darling Marine Center (University of Maine) for reproductive analysis. These samples will tell us how and how much this species reproduces - a key component of how these corals thrive in the fjords and how to protect them for the future. Photo by Chris Rigaud.


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Parque Pumalin

Deep Sea Corals

Huinay Scientific Field Station


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Meet the Author

Rhian Waller
Dr. Rhian Waller is a professor of Marine Sciences at the Darling Marine Center (University of Maine, USA) and specializes in the ecology of deep-sea and cold-water organisms, particularly corals. Rhian has led or participated in over 40 international research and exploration cruises and expeditions to some of the most remote parts of the planet, and has published over 30 scientific papers and book chapters in her 9 year career. She is passionate about educating the next generation of scientists, and conserving our little known deep-sea and polar ecosystems to be studied and enjoyed in the future.