Just another day in the life of the Galapagos Sea Lion

By. Diana Ochoa
For the Galápagos Sea Lion (GSL) living with humans is an every-day adventure. On the inhabited islands, some sea lions share their natural habitat with human settlements. This is particularly enchanting in Puerto Baquerizo Moreno on the island of San Cristóbal where a large reproductive colony around 500 strong dive, swim and sunbathe with residents and visitors. They are famously known for not being aggressive and no evolutionary fear of humans has really ever developed. But, could this be changing?

The Galápagos Sea Lion, in spite of it’s many charms, it remains a wild and endangered species. They suffered a 50% population slump due to two particularly strong “El Niño“ events and population numbers across the archipelago have not recovered. As human settlements grow larger, the number of interactions also increases and with this we have to also take into account the negative ones. There are reported incidences of propeller and fishing related injuries as well as being exposed to domestic pet pathogens. Few misinformed tourists have before touched the young and unfortunately these once isolated incidents are increasing in occurrence. Despite them seemingly well accustomed to humans, the number of factors that could affect these population and species is constantly increasing.

Fortunately, the GSL receives a lot of attention not just from tourists but from researchers too. On San Cristóbal Island a number of studies on behaviour, diet, reproductive rate, endocrinology and immunology indicate that the GSL is very resilient to change. They can adapt their diet to environmental fluctuations and find new breeding sites if their old ones are no longer suitable. However, research as also found that the population on Puerto Baquerizo Moreno may be feeling the effects of stress compared to a populations that don’t live with humans.

All these, although it can sound negative, it has a silver lining. The more we know about the dynamics of this population the better policies can be established to protect and conserve the entire species. It is important to consider that tourism in key in the Galapagos economy and it’s wildlife is the most important selling point. As the GSL is very near the top of the trophic chain, protecting their populations will have wider umbrella effect to all other species lower down in the chain and even across taxa.

Incentives by the Association of Natural Guides of the Galápagos Islands have recently moved towards banning pyrotechnic displays in the Galápagos. Residents and visitors have long reported the distressing response of GSL to fireworks. It is a difficult sight to witness and we can expect it to affect other species too. Over the years this has been a controversial topic but this year, 2017,  it has finally yielded some promising results. The local municipality has approved firework prohibition to be enforced by the authorities and to further ban the introduction of gun powder into the island.

As researchers we must support and encourage conservation efforts on behalf of the local people. This time it may be the GSL leading the fuss but this can only be good for all the Galápagos fragile species.


Brock, P.M., Hall, A.J., Goodman, S.J., Cruz, M. & Acevedo-Whitehouse, K. 2012. Applying the Tools of Ecological Immunology to Conservation: A test case in the Galapagos Sea Lion. Animal Conservation. 

Denkinger, J., Gordillo, L., Montero-Serra, I., Murillo, J.C., Guevara, N., Hirschfield, M., Fietz, K., Rubianes, F. & Dan, M. 2015. Urban life of Galapagos Sea Lions (Zalophus wollebaeki) on San Cristobal Island, Ecuador: colony trends and threats. Journal of Sea Research. 

DPNG – Dirección Nacional del Parque Nacional Galápagos. 2015. Censos Poblacionales de Zalophus wollebaeki. Oficina Técnica de San Cristóbal – Galapagos, Ecuador.

Fietz, K. 2012. General Behavioural Patterns and Human Impact on Behaviour of the Galápagos Sea Lion (Zalophus wollebaeki) on San Cristóbal, Galápagos. MSc. thesis Departament of Animal Ecology and Conservation at the University of Hamburg, Germany.

Ochoa, D. 2015. Identificación y Cuantificación de Metabolitos Fecales de Cortisol en Zalophus wolleabaeki en la isla San Cristóbal Galápagos. Tesis BSc. Universidad San Francisco de Quito-Ecuador. 

Páez-Rosas, D. & Aurioles-Gamboa, D. 2010. Alimentary niche partitioning in the Galapagos sea lion, Zalophus wollebaeki. Marine Biology. 

Trillmich, F. 2015. Zalophus wollebaeki. The IUCN Red List of Threatened Species.

Recent Posts


Follow Us

Scroll to Top

In 2022, the Galapagos Science Center (GSC) and the broader UNC & USFQ Galapagos Initiative will celebrate its 10th Anniversary. We are proud to announce the World Summit on Island Sustainability scheduled to be held on June 26–30, 2022 at the Galapagos Science Center and the Community Convention Center on San Cristobal Island.

The content of the World Summit will be distributed globally through social media and results documented through papers published in a book written as part of the Galapagos Book Series by Springer Nature and edited by Steve Walsh (UNC) & Carlos Mena (USFQ) as well as Jill Stewart (UNC) and Juan Pablo Muñoz (GSC/USC). The book will be inclusive and accessible by the broader island community including scientists, managers, residents, tourists, and government and non-government organizations.

While the most obvious goal of organizing the World Summit on Island Sustainability is to celebrate the 10th Anniversary of the GSC and the UNC-USFQ Galapagos Initiative, other goals will be addressed through special opportunities created as part of our operational planning of the World Summit.

For instance, we seek to elevate and highlight the Galapagos in the island conservation discourse, seeking to interact with other island networks in more obvious and conspicuous ways to benefit the Galapagos Islands, the UNC-USFQ Galapagos Initiative, and the world. We will seize the opportunity to further develop the I2N2 – International Islands Network-of-Networks. Further, we wish to highlight and emphasize multiple visions of a sustainable future for the Galapagos Islands and we cannot do this alone. Therefore, engaging the Ecuadorian Ministry of Environment, the Ministry of Tourism, the Government Council of Galapagos, the Galapagos National Park, and local Galapagos authorities, including government and non-government organizations and local citizen groups, is imperative.

The Galapagos Science Center on San Cristobal Island, Galapagos

Borrowing from Hawaii’s and Guam’s Green Growth Program and the Global Island Partnership, we wish to examine existing global programs that emphasize island sustainability and their incorporation into life, policies, and circumstances in the Galapagos Islands. We will also seek to enhance our connections with the institutional members of our International Galapagos Science Consortium and expand the Consortium through the recruitment of other member institutions. We will also work to benefit islands and their local communities by working with citizen groups as well as important NGOs who seek to improve the natural conditions in the Galapagos and diminish the impact of the human dimension on the future of Galapagos’ ecosystems.

Lastly, we will use the World Summit to benefit UNC & USFQ and our constituencies through a strong and vibrant communication plan about the World Summit, creating corporate relationships as sponsors, identifying funding goals through donors, and benefiting our study abroad program for student engagement in the Galapagos Islands. We plan to develop and issue a Galapagos Sustainability Communique after the World Summit that includes the vision and insights of all its participants for a sustainable Galapagos with applicability to global island settings.

We are eager to hear your perspective and have you join us at the World Summit on Island Sustainability!