We cannot leave the Galapagos Islands without visiting several iconic species. There are the two species of frigatebird, the Red-billed Tropicbird, and of course the boobies.
The two frigatebirds found on the Galapagos Island cross ranges on the Galapagos Island and a few small islands along the Pacific coast of Central America. The Magnificent Frigatebird prefers the warm shallow water regions along the east and west coasts of North America and South America. The Great Frigatebird rules the rest of the tropical waters around the world preferring deeper water.
To tell the difference, one needs to look at the feather sheen, something not visible as they course around the sky, but very evident in nesting birds. The Great Frigatebird has a greenish sheen, the Magnificent shows a purple sheen. The shape and design of these birds make them masters of flying and almost incapable of landing on water or land (except to breed).
While on Genovesa Island, we found numerous Great Frigatebirds on nest.
The Magnificent Frigatebird uses many of the islands, while the Great Frigatebird nest primarily on the northern islands like Genovesa Island. While there is significant overlap, the breeding seasons for each species has different timing. In July and August while we were visiting, the young Magnificent Frigatebirds had dispersed out to the sea, while the Great Frigatebird nest hosted young birds. Both parents care for the babies. One will sit on the nest while the other forages for an average of six days before returning. During that time, they remain totally airborne covering about 1800 miles. A study showed they slept for an average of 42 minutes a day. Like many other birds, frigatebirds can have only one half of their brain asleep at a time for very short periods (unihemispheric sleep). Once back sitting on the nest they could sleep 13 hours a day.
In addition to catching their own food like flying fish and squid, as kleptoparasites, Frigatebirds excel at stealing food from other species. We watched them try to take food out of a baby booby’s mouth as the parent fed them and grab the head of an adult bird trying to make it disgorge the food it brought for its baby. We saw one grab the tails of Red-billed Tropicbirds, holding on until the bird regurgitates the food it was carrying to its chicks. Then, the frigatebird swooped down and grabbed the morsel before it hit the water.
We also watched one repeatedly grab a chunk of a Sea Lion placenta lying on the beach. Since frigatebirds cannot move well on land, this bird would swoop down, and grab a bite as it flew past. Rising back high in the air, it would reproduce the process over and over until satiated.
Frigatebirds also frequently followed along as we motored from island to island.
The Red-billed Tropicbird ranges across the tropics just about anywhere there is an island. Despite being “common,” they are too beautiful to ignore. I could not stop taking pictures of these stunning birds.
They nested in rock crevasses in the tall cliffs on appealing islands, “safe” from predators. We spent lots of time watching them course over the water, sometimes as individuals and often in small noisy groups as they noisily swept past the cliffs containing the nests. Focusing on a single bird, we noticed how it made numerous passes before it eventually came in at just the right angle and speed to settle down.
They feed on fish by diving into the water or plucking flying fish (one of their favorite foods) from the surface.
One cannot visit the Galapagos Island without paying attention to the boobies. There are three types: Nazca Booby, Red-footed Booby, and Blue-footed Booby. The boobies, like our Northern Gannet feed by plunging into the water to grab fish and squid. Their name comes from the Spanish word ‘bobo’, meaning foolish or clown – referring to their clumsy movement on land.
We arrived for nesting season for all three types.
The Nazca Booby a stark black and white bird with an “coral-pink” bill tipped in yellow, plus its larger size and gray feet makes it distinctive on the Galapagos Islands.
A ground nester, a Nasca Booby often chose the center of the defined trails as its nesting site.
We had a fascinating observation of a Nazca Booby interacting with a Great Frigatebird baby as if it were playing.
Thank goodness the Red-footed Booby has red feet as they come in a variety of color morphs. We saw mostly dark morph birds with just the occasional light morph.
This species, unlike the other boobies, nest in trees, preferable up where the sun shines the hottest. This behavior may have helped these birds avoid the depredation caused to ground nesting birds by the introduced rats and cats. Unlike the endemic birds, the Red-footed Booby can be found throughout the tropical oceans.
I saved the best for last, the Blue-footed Booby. This outrageous bird serves as the poster child for the Galapagos Islands. The souvenir stands sell anything with an image of the Blue-footed Booby. Why? Because it is a crazy looking bird and it has a far more restricted range than the Red-footed Booby and has more charisma than a Nazca Booby. Eileen bought a pair of Blue-footed Booby slippers and socks.
We were there during the nesting season. We frequently needed to walk around birds sitting in the path. A circle of guano demarked their nests.
It was raising young season, so we did not see the silly courtship where the male rocks back and forth lifting his feet for his lady to see. While rocking back and forth, the male Blue-footed Booby first raises one foot and then the other, to show its intended. By holding its blue foot so it is contrasted against his white chest he lets her know the quality of this bird as a potential partner. He may do an exaggerated march around her lifting his feet high (goosestepping) to be impressive. Blue-footed Booby adults are considered socially monogamous. They have a partner but do have “extramarital affairs”. Some males deliberately choose a female with grayer feet since she will not be as likely to attract an interloper.
All of the boobies are plunge feeders like our Northern Gannet.
Despite writing five blogs, this barely scratches the surface of the Galapagos Island experience. The islands offer a unique experience. The visits are highly regulated so little damage is done to the islands. Furthermore, the Ecuadorian government continues to plow lots of money into preserving the habitats and species. If readers decide to go, sign up for a boat excursion so you can visit the numerous islands. A visit to just one populated island guarantees one will miss most of the grandeur.
Kricher, John & Kevin Loughin. Galapagos – A Natural History. Princeton University Press, 2022.
Galapagos Conservation Trust – Great Frigatebird https://galapagosconservation.org.uk/species/great-frigatebird/
Gauger Metz, V. H. and E. A. Schreiber (2020). Great Frigatebird (Fregata minor), version 1.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.grefri.01
Galapagos Conservation Trust – Magnificent Frigatebird https://galapagosconservation.org.uk/species/magnificent-frigatebird/
Diamond, A. W. and E. A. Schreiber (2020). Magnificent Frigatebird (Fregata magnificens), version 1.0. In Birds of the World (A. F. Poole and F. B. Gill, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.magfri.01
Galapagos Conservation Trust – Nazca Booby https://galapagosconservation.org.uk/species/nazca-booby/
Galapagos Conservation Trust – Red-footed Booby https://galapagosconservation.org.uk/species/red-footed-booby/
Schreiber, E. A., R. W. Schreiber, and G. A. Schenk (2020). Red-footed Booby (Sula sula), version 1.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.refboo.01
Galapagos Conservation Trust – Blue-footed Booby https://galapagosconservation.org.uk/why-do-boobies-have-blue-feet-2/ Hernández Díaz, J. A. and E. N. Salazar Gómez (2020). Blue-footed Booby (Sula nebouxii), version 1.0. In Birds of the World (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.bfoboo.01
Written by Bob Mercer
Photos and Video by Bob Mercer