Isla San Lorenzo Sur and Isla Rasa
In the Lindblad spirit of adventure and exploration, we investigated a new island this morning. We anchored on the northeast side of rugged Isla San Lorenzo and a few intrepid hikers went ashore for a short, steep walk, while others cruised along the rocky shoreline by Zodiac. Cloud cover gave us some relief from the intense insolation we have experienced during the past days. This area is an extensive nesting ground for the Brown pelican – perhaps the world’s largest. It is a good year, with about 14,000 pairs of pelicans. Most of the chicks were older, or even fledged, with a few downy and even featherless ones remaining at the nest.
Back on board in the late morning, we cruised north in search of marine life. Keen eyes spotted some whale blows, which proved to be fin whales (the second-largest whale) and a few sperm whales as well. A delicious salmon lunch was served in the lounge and we combined eating with whale-watching.
When we arrived at Isla Rasa, we offered Zodiac tours while we waited for the tide to rise enough to enter the inner lagoon. Circumnavigating the island, we found peregrine falcons, American oystercatchers, a few yellow-footed gulls (endemic to the Sea of Cortez), and a surfbird, besides the myriad Heermann’s gulls and elegant and royal terns.
Finally we were able to go ashore and meet Enriqueta Velarde, the woman who has conducted research on Isla Rasa for the past 25 years. Since the introduced rats and mice have been eradicated the bird populations have soared. Upwards of 95% of the world’s populations of both Heermann’s gulls and elegant terns nest densely on part of the 142 acres that make up this tiny island. Over the years, the birds have endured human onslaughts of guano- and egg-collecting as well as natural conditions such as El Ninos, when the entire marine food chain breaks down and the colony does not reproduce. We are fortunate to be able to witness this outstanding wildlife spectacle today.
Visiting Isla Rasa was an overwhelming experience. The birds produced a deafening cacophony. The odors, at first strong and offensive, faded to the rear of our consciousness. The beauty of the birds was stunning. We noticed that many of the terns had come off their crowded nest sites and moved up the hillsides, and that the chicks had formed crèches, allowing both parent birds to go off fishing at the same time. The gull chicks were also found together in their respective age groups.
We also met up with another group of researchers and scientists who are studying Brown pelicans in the Gulf of California. Faced with technical difficulties, they used the power on the Sea Voyager to run their centrifuge to process blood samples from pelican chicks. Meanwhile, Dr. Velarde presented a slide show about Isla Rasa and the work she does there. Lindblad Expeditions supports her and other researchers and projects in Baja California in the “Baja Forever” program.
In the Lindblad spirit of adventure and exploration, we investigated a new island this morning. We anchored on the northeast side of rugged Isla San Lorenzo and a few intrepid hikers went ashore for a short, steep walk, while others cruised along the rocky shoreline by Zodiac. Cloud cover gave us some relief from the intense insolation we have experienced during the past days. This area is an extensive nesting ground for the Brown pelican – perhaps the world’s largest. It is a good year, with about 14,000 pairs of pelicans. Most of the chicks were older, or even fledged, with a few downy and even featherless ones remaining at the nest.
Back on board in the late morning, we cruised north in search of marine life. Keen eyes spotted some whale blows, which proved to be fin whales (the second-largest whale) and a few sperm whales as well. A delicious salmon lunch was served in the lounge and we combined eating with whale-watching.
When we arrived at Isla Rasa, we offered Zodiac tours while we waited for the tide to rise enough to enter the inner lagoon. Circumnavigating the island, we found peregrine falcons, American oystercatchers, a few yellow-footed gulls (endemic to the Sea of Cortez), and a surfbird, besides the myriad Heermann’s gulls and elegant and royal terns.
Finally we were able to go ashore and meet Enriqueta Velarde, the woman who has conducted research on Isla Rasa for the past 25 years. Since the introduced rats and mice have been eradicated the bird populations have soared. Upwards of 95% of the world’s populations of both Heermann’s gulls and elegant terns nest densely on part of the 142 acres that make up this tiny island. Over the years, the birds have endured human onslaughts of guano- and egg-collecting as well as natural conditions such as El Ninos, when the entire marine food chain breaks down and the colony does not reproduce. We are fortunate to be able to witness this outstanding wildlife spectacle today.
Visiting Isla Rasa was an overwhelming experience. The birds produced a deafening cacophony. The odors, at first strong and offensive, faded to the rear of our consciousness. The beauty of the birds was stunning. We noticed that many of the terns had come off their crowded nest sites and moved up the hillsides, and that the chicks had formed crèches, allowing both parent birds to go off fishing at the same time. The gull chicks were also found together in their respective age groups.
We also met up with another group of researchers and scientists who are studying Brown pelicans in the Gulf of California. Faced with technical difficulties, they used the power on the Sea Voyager to run their centrifuge to process blood samples from pelican chicks. Meanwhile, Dr. Velarde presented a slide show about Isla Rasa and the work she does there. Lindblad Expeditions supports her and other researchers and projects in Baja California in the “Baja Forever” program.
