Darwin Bay is a flooded volcanic crater on the south side of Tower Island. Also called Genovesa Island or Isla Genovesa, it is located in the northeast end of the Galapagos Islands, north of the equator.
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| Swallow-tailed gulls |
| Photo © Barb & Ron Kroll |
Southeast trade winds, which occur between May and December, have eroded the caldera, creating an opening through which our Galapagos ship entered and anchored inside the horseshoe-shaped bay.
Swallow-tailed gulls
Within seconds after landing, we spotted dozens of swallow-tailed gulls (scientific name: Creagrus furcatus) with red webbed feet. "Swallow-tailed gulls are the only nocturnal gulls in the world," said Ceci Guerrero, one of our Galapagos cruise guides.
At night, we watched these exquisite gray and white birds glide alongside the M/Y Letty, like ghosts, feeding on flying fish and squid. The ship's movement created bio-luminescence, which attracted the squid. The boat's lights also drew plankton to the surface.
"The undersides of swallow-tailed gulls' bodies are white to reflect light at night," explained Ceci. According to divers, the red rings around their eyes glow at night to attract squid. (Night diving is no longer allowed in the Galapagos.)
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| Adult swallow-tailed gulls preen. |
| Photo © Barb & Ron Kroll |
We watched a pair of swallow-tailed gulls preening in their nest. The female sat on a single speckled egg. Swallow-tailed gulls mate for life. They are endemic (found only in the Galapagos).
Lava gull
Our eyes followed a trail of bird footprints in the sand to a lava gull (scientific name: Leucophaeus fuliginosus). Its black and gray feathers were less showy than the swallow-tailed gull's, but the birds had attractive scarlet eye rings.
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| Sleeping red-footed booby |
| Photo © Barb & Ron Kroll |
Lava gulls are also endemic to the Galapagos. They are very rare. Virtually the entire world's population of lava gulls (400 pairs) are found in the Galapagos Islands.
Red Mangroves
What else is there to see at Darwin Bay, Tower Island? Galapagos red-footed boobies nest in the red mangroves. We photographed one red-footed booby sleeping with its blue beak tucked under its wing feathers.
We noticed another red-footed booby with a fluttering neck. "It's called gular flutter," explained Ceci. "Boobies flutter their gular sac to cool off, just like a dog does by panting."
Ceci explained that there are four species of mangroves in the Galapagos Islands—black, white, button and red. "These Genovesa Island mangroves are called red because the young branches have red bark."
She showed us a cigar-shaped rolled leathery mangrove leaf seedling that is bottom-weighted so it begins to grow when it hits the ground.
Red mangroves (scientific name: Rhizophora mangle) are green year-round. They desalinate water through their roots.
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| Great frigatebird chick in nest |
| Photo © Barb & Ron Kroll |
Frigatebird and booby identification
Along with the red-footed boobies and their chicks nesting in the trees, Tower Island has many great frigatebirds (scientific name: Fregrata minor) and their chicks. We asked Ceci how to distinguish one chick from the other.
"Look at their beaks," she said. "Booby chicks have pointed beaks. Great frigate chicks have hooked beaks."
Older great frigatebird chicks were easier to identify because they had fledged black wing feathers and rust-colored feathers on their faces.
When they become adults, great frigatebirds have a wingspan of 7.6 feet (2.3 meters). "Most of their weight is in their wings," explained Ceci.
Galapagos finches
No visitor to Tower Island can resist searching for the 14 species of Darwin's finches found on the Galapagos Islands. Four species of Darwin's finches are found on Genovesa (Tower) Island.
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| Large ground finch crunches seed. |
| Photo © Barb & Ron Kroll |
"There are two species of cactus finch, the common cactus finch and the large cactus finch," explained Ceci. "On this Galapagos cruise, you will see the large cactus finch only on Genovesa Island and Espanola Island."
As we traveled through the islands of the Galapagos, we checked the finches off our bird lists, from the large ground finch that crunches seeds with its parrot-like beak to the woodpecker finch that uses cactus spines as tools to extract grubs.
One finch species that we did not see during our Galapagos cruise was the vampire finch. "It pecks on the tails of Nazca boobies when they are incubating eggs, so they can't escape even though the vampire finch draws blood," explained Ceci.
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| Whimbrel walks in tidal pool. |
| Photo © Barb & Ron Kroll |
"You can see them at Darwin Island and Wolf Island in the northwest end of the Galapagos. M/Y Galapagos Sky, Ecoventura's live-aboard boat, brings divers to these islands."
Shore birds
At Tower Island's intertidal area, shore and lagoon birds caught our attention. We watched a whimbrel (scientific name: Numenius phaeopus), with a long curved bill, splash through the water.
In another tidal pool, a gray and white wandering tattler (scientific name: Heteroscelus incanus), with shorter legs and a straight beak, looked for food. Ceci helped us identify a ruddy turnstone (scientific name: Arenaria interpres) by pointing out its orange legs.
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| Yellow-crowned night heron |
| Photo © Barb & Ron Kroll |
Yellow-crowned night heron
Just when we though we had seen all the bird species on Tower Island, a yellow-crowned night heron (scientific name: Nyctanassa violacae) emerged from a hole in the rock.
We noticed that his feet resembled the aerial roots of the red mangroves where he feeds. He stretched his wings and intrigued us with a yoga pose, standing on one leg.
All around us we heard squeaks, squawks, squeals, shrieks, whistles, honks and tweets. Shadows of birds with immense wings intermittently shaded us from the sun.
Although this Galapagos paradise is known as Tower Island or Genovesa Island, for us it will always be Bird Island.
TRAVEL INFORMATION
Ecoventura: www.ecoventura.com
Copa Airlines: www.copaair.com
Ecuador Ministry of Tourism: www.ecuador.travel
More things to see & do in the Galapagos Islands:
Punta Suarez Espanola (Hood) Island Galapagos - Christmas Iguanas, Mockingbirds and Blue-Footed Boobies
Fernandina Island Galapagos - Marine Iguanas and Sally Lightfoot Crabs
Punta Espinoza Fernandina Island Galapagos - Flightless Cormorants and Lava Cacti
San Cristobal Galapagos Interpretation Center, Kicker Rock and Playa Ochoa
Santa Cruz Island Galapagos - Lava Tubes and Pit Craters
