Primary Productivity in the Galapagos



Text and images by Natalie Cohen

During October 2014, the Marchetti lab from The University of North Carolina at Chapel Hill  participated on a research cruise in collaboration with GSC and USFQ with the aim of characterizing the phytoplankton community that surrounds the Galapagos Islands. The goal of this project is to begin a long-term survey of the area and to track changes in the phytoplankton community over time, which would allow scientists to tie observed changes in the macrofauna to changes in their food source.

Lowering the CTD with an onboard crane

Lowering the CTD with an onboard crane

Onboard the R/V Guadalupe River, chemical, physical and biological measurements were taken to survey the surface water. These measurements included standing stock biomass, primary productivity, nitrate uptake rates, nutrient concentrations, bacterial and phytoplankton cell counts, light intensity in the water column, temperature, salinity, and turbidity to name a few!

Researchers Natalie Cohen and Carly Moreno in their on-board lab with water filtration setup.

Researchers Natalie Cohen and Carly Moreno in their on-board lab with water filtration setup.

Researcher Carly Moreno, of the Marchetti Lab running light level experiments

Researcher Carly Moreno, of the Marchetti Lab running light level experiments

In order to ensure the scientists had adequate working space for collecting measurements on the ship, a gigantic garden shed was assembled and secured on the deck! In the shed, filtration units and supplies were arranged to facilitate quick water sampling. At around 7am each morning the Captain steamed out to deep water, where a CTD (instrument for obtaining physical parameters) was sent down to 90 meters and collected data every 0.25 second. After bringing the CTD back up and calculating which depth corresponded to desired light levels, niskin collection bottles were sent down to capture seawater. On deck, water was filtered for about 4 hours and preservations were performed. This was a huge effort and couldn’t have been completed without the assistance of the Galapagos National Park and GSC.

There are several useful implications of this research, one being discovering the connection between phytoplankton populations and catastrophic El Nino events. During El Nino years when Galapagos animals such as marine iguanas suffer population loss, do we see a noticeable difference in the phytoplankton assemblages? Can we predict these events before they occur by tracking phytoplankton and physical water properties? If so, could we potentially reduce ecosystem damage caused during these catastrophic events?

Learn more…

about the Marchetti Lab at UNC
about Natalie’s research

Marchetti Lab researcher N. Cohen maintaining the CTD

Marchetti Lab researcher N. Cohen maintaining the CTD

Marchetti Lab and GSC researchers sliding a large volume Niskin bottle into the ocean

Marchetti Lab and GSC researchers sliding a large volume Niskin bottle into the ocean

Galapagos Microbial Communities in the Face of Ocean Acidification and El-Niño


Text by Nataly C. Guevara


Supporting the GSC-PNG large-scale effort a team of researchers from Universidad San Francisco de Quito, University of North Carolina at Chapel Hill, and ESPE University, led by Nataly Guevara from the Leibniz-Institute for Tropical Marine Ecology and Max-Planck Institute for Marine Microbiology, set out on a week-long cruise to explore the potential effects of ocean acidification and El-Niño on key components of the marine carbon cycle. This cruise offered us the incredible opportunity of making the ocean our office, by setting up a sophisticated mobile laboratory and carrying out complex experiments aboard the research vessel.


The cruise preparation took more than 3 months. The acquisition of the materials, reagents, and equipment from mainland Ecuador to the Galapagos Islands was a complex, time demanding task, and far exceeded the expected costs. Fortunately, the GSC supported us during the paperwork nightmare, provided essential lab equipment and some of their most qualified staff. Moreover, experienced personnel of the Galapagos National Park provided their local knowledge on our designated study sites. The perfect team was ready, although the vast amount of material and equipment, had to be moved from San Cristóbal Island to Santa Cruz Island first, where the vessel M/V Queen Mabel was waiting for us (yellow track).



The ocean plays a crucial role of the CO2-balance in the atmosphere. Part of this balance is kept by key processes of the marine carbon cycle. Despite the importance of microbial communities in this cycle, our knowledge of their response to ocean acidification and ENSO events remains rudimentary. The aim of this project, is to study how these stressors affect five mayor components of the marine carbon cycle: The microbial community composition, the concentrations of transparent exopolymer particles (TEP), particulate organic carbon (POC) and dissolved organic carbon (DOC), as well as the potential of forming larger marine aggregates. These processes have previously been studied by using well-defined mesocosm experiments. Nevertheless, laboratory experiments have limitations when attempting to scale-up the effects to real scenarios and tend to underestimate the natural conditions in the ocean.

The Galapagos Islands can be considered as an exceptional natural laboratory, which provided us with three unique oceanographic settings simulating three entirely different experimental treatments:

Treatment B: Roca Redonda, located north of Isabela Island, is an active submarine volcano simulating the conditions of ocean acidification. The CO2 originates from volcanic activity and is released through cold vents, acidifying the water column. Treatment C: The Bolívar Channel, located west of Isabela Island, is well known for its elevated phytoplankton biomass, fueled by an upwelling, rich in inorganic nutrients, and by natural iron enrichment from the island platform. Treatment A: Cowley Islet, located at the East of Isabela was our perfect negative control site. Despite of sharing most of the general environmental conditions with the other two sites, there is neither upwelling nor influence of volcanic CO2.

Between DIVING gear and PIPETTE

At each site we measured environmental parameters such as pH, temperature, salinity, and chlorophyll-a using a multi-parameter CTD. Water samples were collected aboard a small Zodiac using a large Niskin bottle and were transported to the ship to be processed immediately. Sampling at the volcano, Roca Redonda, included an additional component: DIVING! Since the exact location of the volcanic activity had not been previously described, we dedicated one entire day for the site characterization. Here, our sampling methodology had to be adapted! One group was scuba diving in order to measure environmental parameters, collect samples and document the process at the precise positions of the highest volcanic activity, resulting in the lowest pH., After sampling, everybody quickly changed their diving gear for a lab coat.


Watch this short documentary video by ENphocus: Environmental and Nature Photography


The participants: MSc. Maximilian Hirschfeld (GSC), MSc. Daniela Alarcón, BSc. Pablo Andrade (GSC), PhD. Debora Simón, the crew: Capitan Eduardo Rosero, Carlos, Oswaldo, Enrique.

This research project is a joint effort of Leibniz Center for Tropical Marine Ecology (ZMT) GmbH, the Max Plank Institute for Marine Microbiology, the Galapagos Science Center, the Galapagos National Park and the Geology department of the ESPE University.

Photos by: M. Hirschfeld –  ENphocus: Environmental and Nature Photography

Return of the Research Crew


Text and images by Leandro Vaca

The following news summarizes the tidings of our multi-institutional research cruise by the Direction of Galápagos National Park (DGNP), University of San Francisco de Quito (USFQ), University of North Carolina (UNC) and the Galápagos Science Center (GSC). The goals of this large-scale endeavor are to generate base line information on the current state and health of indicator organisms and emblematic species to determine the overall state of the Galapagos’ mayor ecosystems.


The cruise initiated on the 10th October of 2014, taking off from Santa Cruz Island, Pto. Ayora at 8H00 pm. On their way he research crew visited many of the Galapagos’ larger and smaller islands, including Fernandina, Isabela, Pinta (origin of the tortoise Lonesome George), Marchena, Genovesa and Santiago. During the visits to each of the islands we developed the field work and in-situ measurements of oceanographic parameters for our mayor research lines inlcuding primary productivity, Galápagos Sea Lion (Zalophus wollebaeki) and Galápagos Fur Seal (Arctocephalus galapagoensis) censuses, a marine iguanas census, coral community ecology, cetacean sighting, intertidal community ecology as well as micro-plastic pollution.


Research activities were developed at diurnal schedules where tasks were divided between teams working on land and in the marine environment. Field work in the intertidal zone was conducted at various times of the day, coinciding with the ideal low tide conditions exposing intertidal communities.

Blue footed Boobies Marine Iguana feeding

Follow our updates with detailed reports on each of our mayor research lines to be published here on the GSC El-Niño Research Cruise – News Blog.

Preparation of the Cruise

The ORCA I on it's first descend into the blue

The ORCA I on it’s first descend into the blue

During an entire week, until the departure of the research cruise aboard the Guadalupe River, the research team of the Galapagos Science Center and the Galapagos National Park prepared the two week long research endeavor.

The team installed a mobile marine microbiological research lab aboard the cruise ship to support the experiments and sea water treatments of the visiting researchers of the Marchetti Lab at UNC.

In another collaborative effort, marine ecologist Magarita Brandt and USFQ’s engineers Bernard Herrera and Marcia Rueda joined to investigate the communities of vertical walls and their susceptibility to climatic events, such as El-Niño, supported by USFQ’s engineers Nicolás Soria and Sebastián Carillo who custom designed the ROV (remotely operated vehicle) named ORCA I. On a one-day trip to the oceanic islet Gordon Rock, about one hour from the harbor town of Puerto Ayora, we tested the maneuverability of the ROV in oceanic conditions, reviewed the communication between the software interface and the vehicle and tested the multiple video cameras and sensors for environmental data.

After a week of thorough preparation, the ship and the team were ready to embark on the expedition around the entire Galapagos Archipelago.

photos by: Leandro Vaca and Juan Pablo Muñoz



Marine Iguana Health Assessment


From 3 September through 21 September, 2014 a multinational team of marine biologists, veterinary health professionals, and Park Nacional Galápagos (PNG) wildlife officers conducted thorough health assessments of three endemic species on five different islands in the Galápagos archipelago.  Led by University of North Carolina (UNC) affiliated North Carolina State University (NCSU) veterinarian Gregory Lewbart and University of San Francisco Quito (USFQ)/Galápagos Science Center (GSC) biologist Maximilian Hirschfeld, along with Juanpablo Muñoz (USFQ/GSC), Diego Páez-Rosas (USFQ/GSC) and veterinarian Diane Deresienski (UNC/NCSU), and under the supervision of PNG official Maryuri Irlandia Yépez Revelo, the team of over a dozen individuals safely captured, sampled, and quickly released 112 marine iguanas, 30 Galápagos sea lions, five hawksbill turtles, and one green turtle on the islands of San Cristóbal, Isla Lobos, Española, Santa Cruz, and Isabela.

This work is part of an ongoing and expanding collaborative effort initiated by UNC Professor Kenneth Lohmann, with the support and cooperation of the PNG, to establish baseline health parameters that can be readily measured and recorded in the field and laboratory.  Such work is important as these animals are vulnerable to multiple threats including natural (e.g. El Niño events) and anthropogenic threats like human waste runoff, general pollution, and commercial disasters like oil spills.

A rich and dynamic reservoir of information and publications should translate to conservation benefits to these species, and perhaps others, in the archipelago.

Gregory A. Lewbart, 25 September, 2014

 photos by: