From National Geographic: Patagonian Fjords Expedition: Headed Home Happy
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.
It seems like only yesterday we were embarking from Boston to
southern Chile, eager to start the science, eager to see “deep-sea”
corals in a habitat shallow enough that we could reach by SCUBA diving.
And yet here we are, two weeks later, sitting in Santiago airport,
taking stock and finishing up writing dive logs and lab notes.
The last few days of diving and sampling were a whirlwind. Bad
weather and sites where corals had perished unbeknownst to us meant that
coming back from Pumalin Park it was a scramble to get another site
cataloged and sampled and a logger deployed.
The primary objective of this study is to find out how Desmophyllum dianthus
(a cold-water, and usually deep-sea, hard coral) reproduces – vital
information we just don’t know. To be able to investigate reproduction
well, you need samples from different seasons in the same year. This is a
luxury we deep-sea biologists rarely get because of the remoteness of
deepwater sites; because it’s hard and expensive to get ship time and
submersible time; and because the open-ocean environment rarely stays
calm enough to work through 12 months of the year.
The Patagonian fjords however provide the almost perfect natural
laboratory for such a study – they house a deep-sea species living
shallow enough for researchers to sample without using expensive
submersibles and robots, and protected enough within a fjord so you can
sample in every season. Why and how these species (that usually live
below 1500m) exist here we’re not sure, but the high and low latitude
fjord systems provide a habitat similar to the deep sea: cold all year,
dark, and with little competition from photosynthesizing organisms like
A secondary objective is to pick three populations in different
environments (two different fjords and a site close to a salmon farm),
and look at how their reproduction changes in these different areas.
Returning from Reñihué Fjord, I had two sites down – Liliguape, at the
end of the Comau fjord, open to the Gulf of Ancud, well flushed with
oceanic water; and Reñihué, further within a fjord, but a healthy
population, growing tall and large. The next step was to find a site
close to a salmon farm, though everywhere we’d looked, there were not
enough living corals to start this part of the study (you need enough so
you can sample and not impact the population by taking individuals away
So Dan Genter, Chris Rigaud and myself began the search at a few
sites close to the Huinay Scientific Field Station – easily resampled by
the station’s technicians over the next year before I return. With luck
we found an area quickly, deeper than we really wanted (close to
100ft), but with enough live corals to sustain the study, and close
enough to a salmon farm that the corals must be bathed in run-off. With
two dives our goals were accomplished: deploy the logger (measuring
temperature, salinity and light), perform photographic transects, and
collect specimens to send back to my laboratory.
This left us with just one day to spare, and we were lucky enough to
have the station’s director, Vreni Haussermann, take us on a dive to
another coral area to collect not live corals, but fossil corals for a
collaboration with a geochemist friend of mine.
This was possibly one of the most beautiful dives of my life, and it
was instantly apparent why the station’s scientists are preserving this
site (no live corals are ever taken from this area). At 90ft depth and
going back into the bedrock for over 15ft was a cave, the ceiling
covered in Desmophyllum corals as far as flashlight would shine. Even a
stray air bubble would be enough to knock these fragile creatures from
the ceiling above. We set to work in the tall piles of fossil corals
lying at the bottom of the cave, showing just how long these deep-sea
creatures have been living in the fjords. An amazing site, and an
amazing last dive of this expedition.
With a little sadness we returned to the station and began packing equipment and samples for the long ride home.
But I’ll be back next year – to collect the loggers and download
their valuable data, to inventory the samples the assistants at the
Huinay Scientific Field Station will have collected for me, and to dive
once again in fields of (usually) deep-sea corals.
I would like to thank the fantastic help and assistance given to
this expedition from all those at the Huinay Scientific Field Station –
this expedition and valuable science could not have been done without
you – Muchas Gracias!