Our day began early as we sailed into the flooded caldera of Genovesa Island, a horseshoe-shaped remnant of a volcanic eruption in the far northeast of the Galápagos archipelago. The island’s circular shape shows its origin: a volcanic crater that collapsed inward after an eruption, allowing seawater to pour in and create a protected bay.
Often referred to as “Bird Island,” Genovesa supports immense colonies of seabirds, making it one of the most densely populated bird habitats in the Galápagos.
An Island Full of Birds
Genovesa is a sanctuary for seabirds, and nowhere is that more obvious than along the Prince Philip’s Steps trail. From the moment we landed, it felt like we were walking through a live aviary. Every few feet revealed different birds. First, we saw the Nazca boobies. These large, white seabirds with black-tipped wings and yellow eyes are one of the iconic “Big 15” species of the Galápagos. We saw both attentive parents and their fuzzy, down-covered chicks. Some of the chicks were already testing out their wings, flapping them clumsily as they stood in place.
The Nazca boobies didn’t seem to care about our presence. Some sat in the middle of the trail, forcing us to detour. They didn’t beg for food or try to flee. It was clear we were in their space. They looked at us with curiosity, as if evaluating our behaviour. One was even attracted to the bright coloured shoes of someone in our group. We joked at the bird was imprinting on them.
We also encountered several red-footed boobies up close (another Big 15 of the Galápagos ). Unlike the Nazca or blue-footed boobies, red-footed boobies are smaller and more agile in flight, using their dexterity to catch flying fish. They are also the only booby species in the Galápagos that nest in trees, thanks to their strong, grasping feet. Their nesting behaviour allows them to avoid the crowded ground-level colonies favoured by other species.
We also observed many great frigatebirds nesting. We had the fortunate of seeing the males with their red throat sacs inflated like balloons. However, we didn’t see the closely related magnificent frigatebird, which looks nearly identical but differs subtly in iridescent sheen and eye ring.
Further along the trail, we also spotted one of the iconic Darwin’s finches. This one was a brown finch, and though we knew it belonged to one of the local species, it was remarkably difficult to tell whether it was the small, medium, or large ground finch. These species differ primarily by the size and shape of their beaks, which have adapted to different types of seeds. In the field, even seasoned naturalists can find it tricky to differentiate them without observing feeding behaviour or using binoculars to compare subtle proportions. Genovesa is home to several of these species.
Spotting Rarities with a Naturalist’s Eye
We were lucky to be hiking with someone in our group who had spent decades as a professional naturalist. Her eye for detail helped us spot species we would have otherwise missed, including Galápagos doves nestled in a rocky crevice.
Our naturalist companion was able to spot the elusive short-eared owl. The short-eared owl is the only owl on Genovesa and is a daytime hunter, adapted to prey on storm petrels that nest in the island’s lava crevices. Seeing one is considered a highlight by bird enthusiasts.
She spotted this owl even when swarms of birds circled the crater. From a distance it looked like hundreds, maybe more.
I asked the guide how often people got pooped on by birds, and he said “all the time”.
How Did the Birds Get Here?
As we observed the vast diversity of birdlife on Genovesa, a natural question arose: how did all these birds get here in the first place? Genovesa, like all the Galápagos Islands, is of volcanic origin and has never been connected to any continent. That means every species had to arrive by sea or air. In the case of birds, it’s a mix of seabirds and land birds that flew in from the mainland over generations.
Seabirds like the Nazca booby, red-footed booby, and great frigatebird are strong fliers capable of covering vast distances over open ocean. They likely reached the archipelago by chance during migration or storms, eventually settling and breeding. Unlike land birds, which evolved in relative isolation after their ancestors arrived, many seabirds still travel between islands or even back to mainland South America during their lifetimes.
Land birds, such as the Galápagos dove and finches, probably arrived in earlier periods via rafting or wind dispersal and then adapted to island life. Their more limited range makes their evolution within the islands more distinct and well-documented.
Circumnavigating the Crater
After the hike, we boarded zodiacs for a ride around the inner edge of the caldera to get a better sense of its geologic origins. The steep, eroded walls of the crater revealed layers of volcanic tuff – compressed ash from past eruptions. In places, erosion had carved angular overhangs and caves. The crater rim is breached on one side, allowing the ocean to flood in and creating a calm anchorage for small vessels like ours.
Along the cliff face and the trees above, we continued to see more birds nesting. There were even some marine iguanas resting on rocks.
Courting Frigates and a Nap in the Sand
After lunch, we embarked on another short nature. Right as we began, we passed a sea lions sprawled out comfortably on the sand, fast asleep. They lay there without a care in the world, entirely unfazed by our presence. Many Galápagos animals are not concerned with human visitors, as long as we respect their space.
As we continued, we came across a group of nesting frigatebirds in full courtship display, with their bright red throat sacs fully inflated. They flapped their wings, made rattling calls, and shook their inflated sacs in dramatic fashion – all in an effort to catch the eye of a passing female. The sounds and motions were loud and theatrical.
Our guide mentioned research into their mating behaviours, including experiments where scientists altered the appearance of the sacs by painting them blue. Surprisingly, the colour change didn’t seem to affect female interest. In another case, a researcher punctured the sac to study healing – and it reportedly repaired itself within a few days. These stories underscored how much remains unknown about even the most visible species.
A Cloudy Snorkel and Playful Sea Lions
We ended the day with a snorkel along the rocky beach. Unfortunately, the water was too cloudy to see much underwater life. The coarse volcanic rocks made walking on the beach difficult; a few of us got small stones lodged in our flippers, which rubbed uncomfortably against our skin.
But the snorkelling wasn’t the real highlight. Back on shore, a group of sea lions came ashore and began to play. They chased one another, nipped each other’s flippers, rolled onto their backs, and flopped in and out of the surf in an endless loop of games. Their energy and antics entertained us for nearly twenty minutes.
One thing we noticed throughout the trip was the near absence of native terrestrial mammals or amphibians on the islands. Unlike birds or reptiles, which can fly or survive extended periods at sea, most land animals couldn’t make the crossing from the South American mainland. The Galápagos are over 900 kilometres from the coast, and animals unable to float, fly, or raft on vegetation simply never had the chance to colonize these remote islands.
See here to view the full photo album from our day on Genovesa Island.
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