Rising sea temperatures threaten wildlife on the Galápagos Islands

The Galápagos Islands are world-renowned for their many unique animal species, but those species are not infinite in number.

The marine iguana in particular, which is unique to the Ecuadorian archipelago, constantly struggles to find the red and green algae it prefers.

The island’s unique sea turtles are also struggling to live in the rising temperatures, which, among other things, lead to fewer and fewer nutrients for the young turtles that will grow large.

– We have a bit of everything here, which is why many believe the Galápagos Islands are so diverse. But at the same time we only have a small number of each of them, says naturalist Natasha Cabezas.

Warm seas lead to food shortages

The islands have always been exposed to changes in sea temperature. The archipelago is located almost directly on the equator, at an area in the Pacific Ocean where several ocean currents meet. This means that cold water comes up from the south, while warm water comes down from the north.

In addition, one must take into account the weather phenomenon El Nino, the natural climate phenomenon that warms parts of the Pacific Ocean every two to seven years.

The temperature in the sea varies a lot from season to season, but in general it just gets warmer and warmer. 2023 was a record year for ocean temperatures in the world’s oceans, including the Pacific Ocean.

Winter

In early June, it is winter in the southern hemisphere, and the so-called Cromwell Current brings whale sharks, hammerhead sharks and sunfish to the surface. The cold current also carries nutrients for penguins, marine iguanas and sea lions that are in search of food.

Over the past year, researchers have studied how the weather phenomenon El Nino can affect the many unique species on the Galápagos Islands.

It was also found that El Nino can lead to food shortages for the marine iguanas and sea turtles. Since last year’s El Nino, scientists have discovered that several of the species on the islands have decreased in number.

– The marine iguanas were one of the species most affected by El Nino last year, says nature conservation director for the islands, Jorge Carrión.

Alien animals threaten land species

While rising ocean temperatures threaten wildlife in the sea, species on land have a different problem. Free-roaming animals such as cats, dogs, pigs, goats and cows threaten wildlife on land in the archipelago.

According to Cabezas, many residents of the island have abandoned dogs and cats they adopted during the corona pandemic.

– If you don’t take care of them, they become a problem. It is a shame that you now see dogs everywhere. We were a big problem, and we don’t know what to do, she says.

Truer

The non-native species may especially threaten the giant tortoises of the Galápagos Islands.

– In one night, a wild pig can destroy all the turtle nests in an entire area, says Carrión.

He further explains that park rangers visit nesting areas once a day, and that they then kill wild pigs in the area. But the pigs can be volatile.

Wild cats on the island live on the offspring of the sea iguanas, and both the pigs and the cats fight for the same food as the giant tortoises.

Plastic in the ocean

But rising sea temperatures and alien species are not all that threaten the animals on the Galápagos Islands.

In addition, plastic is an ever-increasing problem in the world’s oceans. A recent study showed the discovery of microplastics in the stomachs of the penguins on the archipelago.

– There are no animals on the Galápagos Islands that do not have microplastics in their food, says Carrión.