Oceanografía en Golfo de Penas

Franco and Seba Checking the CTD

Transcurrían los primeros días del 2016 cuando la Fundación Huinay lanzó una invitación para participar en una expedición científica (HF27) por los canales y fiordos de la Patagonia Chilena. La finalidad principal sería buscar respuestas concretas a la mortalidad masiva de ballenas que ocurrió en la zona norte del Golfo Tres Montes (i.e., Seno Escondido, Seno Newman y Seno Slight). Si bien yo estaba enterado del suceso por los medios masivos de comunicación, la información no era clara respecto a cuál era la magnitud del evento, ni qué tipo de escenario nos ibamos a encontrar. Al llegar al lugar nunca pensé que sería tan interesante hablando desde un punto de vista científico y además emocional. En esta ocasión mi labor como Oceanógrafo sería realizar una caracterización oceanográfica de las propiedades físicas y biogeoquímicas de capa superficial de la columna de agua, midiendo variables como salinidad, temperatura y oxígeno, mediante perfiles continuos realizados con un CTD SeaBird 25, y muestreos discretos de nutrientes (i.e., NO3-, NO2-, PO43- y Si(OH)4) y gases (i.e., N2O, CH4) sobre la capa de mezcla, siendo el regístro de metano muy importante debido a que éste se genera mediante procesos biológicos asociados a la descomposición de los cadáveres de cetáceos. Todas estas muestras serán posteriormente analizadas en el Laboratorio de Biogeoquímica Isotópica de la Universidad de Concepción.

En un comienzo no sabía el grado de importancia del proyecto en el que me estaba involucrando, pero una vez en el lugar pude corroborar con mis propios ojos el por qué de la urgencia de realizar esta expedición. Es impresionante la cantidad de ballenas muertas que se encuentran atrapadas entre los pequeños canales y/o minúsculos islotes característicos del lugar, pero lo más impresionante, es que aún no existe una explicacion clara  en determine la ocurrencia de este fenómeno, ni tampoco existe interés gubernamental de apoyar este tipo de expediciones. Recordemos que anteriormente se detectaron aproximadamente 337 ballenas en las distintas zonas de estudio y hasta ahora llevamos ~65 cadaveres, quedándonos muchas estaciones biológicas y oceanográficas por analizar (es probable que el cómputo final sea aún mayor). En mi caso, teniendo una formación oceanográfica principalmente física y biogeoquímica, esta situación es bastante impactante, ya que pasé de estar horas y horas procesando datos en un computador a interactuar con una disciplina de la ciencia para mi desconocida y mucho más complicada… La observación en terreno de cadáveres de cetáceos en descomposición, donde hay que tener “cuero de chancho” como se dice en Chile; que es equivalente a ser fuerte y aguantar con ímpetud el escenario adverso (e.g., muy malos olores, insectos y grasa de ballenas por todos lados), en definitiva un escenario lamentablemente devastador.

Respecto a las mediciones que hemos realizado con el CTD, preeliminarmente podemos mencionar que son notables las temperaturas superficiales que hemos registrado, en algunos casos han sido muy altas teniendo en cuenta la zona donde nos encontramos (~10 °C, Silva et al., 2002). De 16 estaciones realizadas, la menor temperatura superficial se registró en la posición geográfica de 47° 47.701’ S 74° 57.663’ W, con un valor de 15.7 °C y la mayor temperatura en la posición 46° 50.050’ S 74° 35.260’ W, con un valor impresionante de 21.2 °C, ambas en la zona del Seno Escondido. Para explicar esto rápidamente y sin mayor análisis, un oceanógrafo culparía al fenómeno climático y oceánico que estamos viviendo hoy en día, el mayor “El Niño” registrado en la historia, recordemos que este es un fenómeno generado en el Pacífico Ecuatorial, pero que transmite sus consecuencias hacia gran parte del globo terráqueo, entre ellas a la zona del pacífico sur oriental (austral).

La expedición hasta ahora ha sido maravillosa, el clima en esta región es muy cambiante, ya que podemos tener una linda mañana de sol navegando por los canales australes, pero en el transcurso de unas horas se desata una lluvia que en la zona  central de Chile (lugar donde vivo) no se ve. Como anécdota puedo contar que tuvimos que realizar una de las más temidas de las estaciones programadas: casi en la mitad del Golfo de Penas!! (47° 1.863’ S 74° 55.952’ W), con un viento constante de 20  nudos y rachas de 30 nudos!!, el movimiento del velero no impidió que pudiésemos realizar nuestro hermoso perfil de CTD a 100 m de profundidad, además del muestreo de gases y nutrientes, muy valioso para nosotros porque son pocos los que se atreven a caracterizar este movido y temido Golfo, acá mayormente conocido como “Golfo del Vómito”.

Aún quedan muchas millas que navegar y muchos perfiles y estaciones que realizar, el ánimo está cada vez mejor, el trabajo grupal es lo mejor de la expedición, todos provenimos de distintas áreas donde nos llenamos y aprendemos un poco de todo, cada uno aportando un granito de arena.

Seba García-loyola

Golfo de Vómitos

 

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“Keri, kill me. Kill me please!” -Fernanda, Golfo de Vomito. (c) Keri-Lee Pashuk 2016

La mañana del 10 de Febrero comenzó muy tranquila. Luego de visitar una hermosa playa (con frutillas silvestres incluidas), nos embarcamos rumbo al Golfo Tres Montes, al Norte del Golfo de Penas. La navegación empezó como de costumbre: muchas cosas que ordenar, revisar mapas y planificar el viaje. Todo transcurrió bien hasta el medio día. Lentamente, el barco comenzó a moverse con mayor intensidad. Casi al medio día, Fernanda se sintió mareada y bajó a la cama. Cada segundo me sentía mas mareada por lo que decidí bajar a la cama (la peor decisión ever!!). Todo sucedió muy rápido. Bajé y de repente mucha agua cayó desde el techo. La escotilla había quedado abierta!!! Si bien eran unos pocos milímetros, fue suficiente para que todo quedara empapado. La escena era super patética. Fernanda y yo estábamos completamente mojadas, pero éramos incapaces siquiera de movernos de la posición en la que estábamos en la cama (así que permanecimos mojadas el resto del día). Durante las siguientes 5 horas, el barco se movería sin parar. Había momentos que debíamos afirmarnos de la cama de arriba para no caer de la cama. De vez en cuando escuché a Fernanda vomitar (luego me enteré que fueron 4 veces). Recién a las 11 de la noche pude salir de la cama. Alex estaba acostada en el living quejándose de su espalda comiendo papas fritas junto a Franco. Fernanda despertó con cara de espanto. Mas tarde, los chicos nos mostraron los videos del exterior del barco durante la navegación en el Golfo. Ahí supe que pasamos por olas en promedio de 3 metros y que las mismas condiciones del clima se repetirán por varios días mas.. Hoy volveremos a salir a aguas abiertas. Supongo que nada puede ser peor que ayer pero con el Golfo nunca se sabe

Ana

Serendipitous Strawberries

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It’s true. Photo by Katie

by Greg Landreth

February 13, 2016

We have now parked the boat in a place called Puerto Barosso, a favourite anchorage for the(few) fishernmen who are working the seaweed harvest in these parts. It is easy to see why they choose this place, parked right on the edge of the Gulf OF Penas as it is. Yesterday we were working our way slowly across the Gulf from the east doing the CTD casts when a strong breeze from the north started to work on the long SW swells. We took a last cast right out in the middle of the Gulf, (the one I thought we would not be able to get, as it was  the furthest out!) and scarpered for shelter. Fortunately we had been in here before and I was able to follow my GPS track from last year. Even so, it is a great relief to know that the entrance is uncomplicated, free of dangers, and the anchor holds well.

Saoirse is well equipped to be sneaking into these kinds of places in the dark, It must be
noted that this area is very thinly explored, even the charts I have of this bay are up to
two miles out. Our late arrival this time was due to an amazing discovery some 40 miles away on the other side of the Gulf. Yesterday I had threaded the needle in reverse, following Saoirse’s track out of the narrows guarding the inner anchorage at Seno Escondido. With the San Quintin Glacier again as backdrop, Saoirse ran back east down the coast, shepherding Keri and the “girls” who were surveying the whale skeletons in the dinghy back down towards the end of Peninsula Forelius. The idea was to rendezvous there and scope out a possible anchorage for the night, ready to take on the crossing of the Gulf early the next morning since the weather forecast was as promising as it could be. Entering a huge shallow bay, I could only get the boat to within a mile and a half of the beach. Snatching the last sunshine hours of the day we sprinted in to the beach hoping to be able to cross over what appeared to be some sand dunes and take a look at the swell crashing onto a double isthmus on the windward side. Katie had been hoping to take her surfboard over there, but I had to veto the idea as time, as always, was pressing.

The others took off like hares down the smooth sandy beach, having been confined to the boat for the day. I anchored the dinghy and strolled on across the dunes to see what could be seen. It is usual in Patagonia to watch where one is putting ones feet, as the native ground cover here is uniformly spiny and unkind to the touch, but halfway across the isthmus I suddenly bent down to look at something that looked entirely like a strawberry plant growing out of the sand. A strawberry? It couldn’t really be, could it?

There is a native “frutilla” which grows in the far south of Patagonia for which we occasionally forage for in summer that has the appearance of a tiny strawberry but this plant looked exactly like those which I had picked in the family garden when I was young. Bending down I was astonished to find a perfect, round, red strawberry hanging below the plant. A taste test quickly confirmed it, no doubt about it. Well, I supposed, that where there is one there has to be more. I raised my gaze to be greeted with a stunning sight. For hundreds of meters all around, the sand dunes were covered with strawberry plants, acres and acres of them, literally the “Strawberry Fields Forever”. With that song running round and round in my head, we filled hats and whatever we could carry with the ripe, round fruit and returned red-lipped to the boat.

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Sandy strawbs which barely made it back to Saoirse -photo by Katie

Imagine the heaven we were in when, close to the boat we were greeted by Keri waving the
three fat fish which some fishermen had dropped off while we were gone. We feasted greatly that night, alleviating the image of Patagonia as a lonely place of starvation and death.

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(c) Keri-Lee Pashuk 2016

 

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(c) Keri-Lee Pashuk 2016

 

February 7, 2016

The crossing of the normally volatile Golfo de Penas from the south turned out this time to be almost a non-event. Waiting a day near Isla Wager for the perfect weather conditions turned out to be by far the best course of action. Not only were we treated with calm conditions for the crossing, we were also able to navigate inside Isla Javier, something I had thought we would never have the opportunity to do since the sea conditions must normally be extremely dangerous in the prevailing west winds. Good thing we did, since this narrow Strait seems to be home to hundreds of whales, and the views of the Northern Patagonian Icecap are other-worldly.

We have burrowed our way into Seno Escondido, a 5-mile long, shallow and tortuously winding sound nestled below the curve of the Taitao Peninsula. The sound itself is mostly navigable by eye, keeping to mid channel, but the entrance from Bahia San Quintin took a bit of careful juggling with the state of the tide and a thorough reconnaissance by Keri and Katie in the dinghy. Towards evening last night we reluctantly gave up our magnificent vista of the vast San Quintin Glacier pouring out of the ice-cap and entered the inner bay, taking advantage of low-slack tide to navigate the islands and sand bars encumbering the entrance. It was worth the extra grey hairs to enter this protected inner bay, since we are now protected from all winds and can concentrate on the work at hand.

Though the weather has been holding since yesterday, the slowly increasing breeze from the NW turns out to be a blessing in disguise. A first encounter with a beach lined with slowly decomposing whale carcasses is a gut wrenching sight at best, but the wind is doing wonders sweeping away the aroma that has been permeating the boat in the last couple of days. I’m not sure that there is any way to ever get used to the smell of dead whales, but I am certain that we will all be glad that Saoirse has a built-in shower once we start working in closer proximity.

As is the same in almost any expedition which is uses boat access to terrestrial sites, now is a critical time. With the oceanographic work taking place mostly aboard Saoirse, and the whale-skeleton surveys taking place on shore at the same time, the general efficiency of changing over from pure navigation mode to include shore side work is of paramount importance. Normally Saoirse would be solely committed to the support of one party, but with multiple studies going on at once in widely separated areas, attention to safety and preparedness for things going wrong must form the basis of further action. More on that tomorrow.

Whale Study Intro

Eating on the Run - Angostura Inglesa
20 hours after arriving in Puerto Eden, on the run, heading north to Golfo Tres Montes for the Patagonia Project Mass Whale Mortality Study

Somewhere south of Puerto Eden, against the usual backdrop of glaciers and their attendant rock faces and somber valleys, I am standing on the front deck of Saoirse swinging a strange contraption called a Niskin bottle into the fiord, pulling up samples of water from various depths. Normally my gaze would be raised to the glaciated peaks, mentally stringing together routes that I will probably never get to traverse, but today the focus is downward into the depths. Today’s, and indeed this years focus is science. The simple visceral joy of putting boots on rock is replaced by the long-term teasing out of the secrets of the Patagonian fiords, how the forces of nature interact to create the land and seascapes we traverse today.

To see how we came to be fishing for water in the Patagonian Fiords we need to back up a few years. After 15 years of plying the waters of Antarctica and Patagonia on expeditions which were mostly involved with voyaging, or the sport of climbing new mountains and seeing new sights, We began to become interested gradually in science, not only because becoming involved in it puts us again at the edge of what is known, but also because it requires us to visit places which are well off the normal tracks of vessels, The added challenge of having to do an absorbing and important work once we get there certainly uses all of the skills we have accrued on these last voyaging years, and then a vast set of new ones. It is as if all the learning has to start again.

Our first forays into scientific field work were mostly in geology, visiting wild and crazy rock formations buried in the fiords of the Cordillera Darwin, carrying scientists of all nationalities to puzzle out the tectonic history of the range. Following this came bottom sampling of the fiords, pulling up foraminifera from the ocean floor 300 metres down. This of course all involves special equipment, and it was certainly a challenge to house and operate hydraulic winches on the heaving deck of a sailboat. Then came scientific diving, baseline studies of the benthic life over a thousand miles of coastline. At that point we had to opt for the range and autonomy of a larger and more powerful boat (still with get-you-home security of a sailing rig). This boat, called “Saoirse” we bought in Greenland two
years ago and brought her here for a new life exploring the southern fiords.

Now here we are engaged in what we think may be one of the most important studies yet. Last year as we were in the Golfo de Tres Montes supporting the divers from the Huinay Scientific station doing baseline surveys of the benthic marine life here, we began to notice an inordinate number of whale carcasses on the beaches. We didn’t know it then, but this would be the biggest whale mortality in recorded history. This hit the international press quite some time after the discovery, but it took until now to find the resources to return to the area to make the necessary studies to find out what happened here, and why.

Keri Pashuk & Greg Landreth