Exploration around the Galapagos Marine Reserve (RMG) found a greater number of pups of sea lions and fur seals and that the health status of marine iguanas is positive

A team of researchers sailed around the archipelago with the aim of obtaining updated information on the population and health status of several emblematic species of the islands.

The expedition was made up of scientists from the Galapagos National Park Directorate (DPNG), the Universidad San Francisco de Quito (USFQ) and the University of North Carolina at Chapel Hill (UNC) through the Galapagos Science Center (GSC).

The Galapagos Islands are famous for their biodiversity and have been the subject of scientific study since the time of Charles Darwin in the 1830s. This extraordinary biodiversity is due to the fact that they are located at the convergence of three marine currents that generate unique ecological conditions within and outside the archipelago, reports the USFQ.

Preliminary results indicate that oceanographic monitoring determined that the water was colder than in previous years, with a temperature range several degrees below average for the time of year in which the exploration was made, which was last November.

The results of the population census of sea lions and fur seals showed a greater number of pups on the islands of San Cristóbal and Floreana, and on the islands of Fernandina and Isabela, in that order.

Also, the census of marine iguanas recorded a total of approximately 36,000 individualsof which the health status of 70 specimens was monitored with positive results.

Since 2014, the DPNG, USFQ and the University of North Carolina at Chapel Hill (UNC), through the Galapagos Science Center (GSC), have jointly carried out a project with the aim of navigating around the archipelago.

During the journey, updated information is obtained on the population and health status of several emblematic species, such as sea ​​lions, fur seals, iguanas and sea turtlesin addition to evidencing the effects of climate variability within the Galapagos Marine Reserve (RMG).

“During the years 2020 and 2021, although the inter-institutional work was paused due to the COVID-19 pandemic, the DPNG continued with the monitoring, generating valuable information for the management and conservation of the islands,” indicates a bulletin from the USFQ.

The cooperative work between institutions and researchers allowed a new scientific research and monitoring expedition to be carried out at the end of 2022, in which the same methodologies as previous years were applied, but this time under climatic conditions related to La Niña.

“This climatic event is opposite to El Niño, that is, the sea cools due to a greater number of upwellings and it is speculated that there is greater marine productivity, increasing the availability of food and providing more favorable conditions for several species. With cold water, there are more nutrients, therefore, it is expected to see a higher primary productivity, which in turn leads to a change in phytoplankton species, from small to larger”, adds Adrián Marchetti, GSC researcher. and UNC professor.

These research and scientific monitoring cruises have been carried out annually from 2014 to 2019, obtaining important results on the adaptations that these species acquire during and after warming periods such as El Niño. This climatic event is characterized, instead, by generating a warming in the ocean that decreases the marine productivity of the region, generating conditions that lead to less availability of food for marine/coastal consumers.

“The El Niño event causes food stress to be generated in several of the emblematic species of the GMR, exposing them to mortality or changes in their ecological behavior,” says Diego Páez-Rosas, a GSC researcher and USFQ professor.

In November 2022, the team of twelve researchers from the USFQ, UNC and DPNG, along with eight crew members from the Sierra Negra boat, traveled a total of 14 islands and 30 specific sites, distributed around the GMR, for 16 days.

The purpose of the research was measure numerous oceanographic parameters, such as temperature, salinity, nutrient concentration, primary productivity, and plankton community compositionwhich could be impacted by La Niña conditions.

Also, the monitoring of the emblematic species of Galapagos, including sea lions, fur seals, iguanas and sea turtles, and the evaluation of the impact of plastic and microplastic in the marine environment.

This information will be used by the DPNG researchers and team to understand the health status of several of these species considered sentinels or bioindicators of the ecosystem, in order to assess the effects of climate change on Galapagos ecosystems and potentially help with decision making on how to preserve the reserve.

Meeting these goals is often difficult, so the scientists employed innovative methodologies and techniques, such as population monitoring with the help of dronessays the USFQ statement.

“Because access to the reproductive colonies of these species is very difficult and sometimes impossible, the idea of ​​covering these areas with overflights is an opportunity to generate more information,” says Jennifer Suárez Moncada, DPNG park ranger.

The scientists are analyzing the data obtained in their laboratories to create scientific information that will be delivered to the DPNG and presented to the world in the form of scientific articles that are expected to be published during 2023, says USFQ. (YO)