Fernandina
The black basaltic shorelines of the Galapagos Archipelago, though seemingly uninviting from afar, are home to a great concentration of life forms, including algae, invertebrates and vertebrates.
During our morning outing, we strolled or took Zodiac cruises along the shores of the youngest island of the group, Fernandina. Conditions for these activities were optimal, as the tide was low, exposing much of an area known as the intertidal zone. This is a fascinating aspect of rocky shorelines around the world: an extremely narrow fringe area, a few meters in extent, between the high and low water marks. Galapagos has a tidal range of approximately 1.9 meters, or almost 8 ft, so the shorelines of these islands sport a marked intertidal area. Despite the restricted size of this zone in comparison with other marine habitats, the environmental conditions along the gradient of these shores vary more than anywhere else: the higher up the shore, the more exposure to air, sunlight and wave action; whilst lower down, where physical conditions are more favourable, organisms are subjected to higher pressures from predation and competition. Sessile or slow moving organisms, such as different algae species, barnacle, oysters, sea anemones, sea urchins, seastars and various mollusks, are distributed vertically up these shorelines according to their specific physical and morphological adaptations. Those organisms more highly tolerant of exposure, such as barnacles, live higher up among the breaking waves, those that are superior competitors, voracious predators or less tolerant of exposure occur lower down. Several motile species follow the advancing and retreating tides up and down the coast, including our unique marine iguana, the only sea-going lizard in the world, and the most conspicuous of them all: the brightly-coloured Sally Lightfoot crabs, which scurry over rocks left uncovered by the receding waterline, scavenging and grazing.
The multitude of organisms inhabiting the area and periodically exposed, are magnets to many species of shorebirds, both resident and migratory, such as the American oystercatcher and many heron species. Our endemic heron is the little lava heron – a small compact bird, virtually invisible on the black lava, that stalks, prowls and pounces on its prey in an amazingly feline way. It was a real treat getting to observe the clever technique employed by these little predators to eat a crab caught after much effort. The heron will start by removing all the crabs’ legs, then swallow the body whole, after which it will pick up the legs, one by one, wasting nothing!
Our spectacular morning was topped off by an encounter with a large pod of bottlenose dolphins, which we approached by lowering our Zodiacs and riding amongst them. The pod included mostly females, and some very young calves, many practicing their breaching in an endearing way.
Truly a day to celebrate, which we did during our cocktail on the sky deck while circumnavigating Roca Redonda, the remote remains of a once magnificent volcano, against the backdrop of a spectacular sunset.
The black basaltic shorelines of the Galapagos Archipelago, though seemingly uninviting from afar, are home to a great concentration of life forms, including algae, invertebrates and vertebrates.
During our morning outing, we strolled or took Zodiac cruises along the shores of the youngest island of the group, Fernandina. Conditions for these activities were optimal, as the tide was low, exposing much of an area known as the intertidal zone. This is a fascinating aspect of rocky shorelines around the world: an extremely narrow fringe area, a few meters in extent, between the high and low water marks. Galapagos has a tidal range of approximately 1.9 meters, or almost 8 ft, so the shorelines of these islands sport a marked intertidal area. Despite the restricted size of this zone in comparison with other marine habitats, the environmental conditions along the gradient of these shores vary more than anywhere else: the higher up the shore, the more exposure to air, sunlight and wave action; whilst lower down, where physical conditions are more favourable, organisms are subjected to higher pressures from predation and competition. Sessile or slow moving organisms, such as different algae species, barnacle, oysters, sea anemones, sea urchins, seastars and various mollusks, are distributed vertically up these shorelines according to their specific physical and morphological adaptations. Those organisms more highly tolerant of exposure, such as barnacles, live higher up among the breaking waves, those that are superior competitors, voracious predators or less tolerant of exposure occur lower down. Several motile species follow the advancing and retreating tides up and down the coast, including our unique marine iguana, the only sea-going lizard in the world, and the most conspicuous of them all: the brightly-coloured Sally Lightfoot crabs, which scurry over rocks left uncovered by the receding waterline, scavenging and grazing.
The multitude of organisms inhabiting the area and periodically exposed, are magnets to many species of shorebirds, both resident and migratory, such as the American oystercatcher and many heron species. Our endemic heron is the little lava heron – a small compact bird, virtually invisible on the black lava, that stalks, prowls and pounces on its prey in an amazingly feline way. It was a real treat getting to observe the clever technique employed by these little predators to eat a crab caught after much effort. The heron will start by removing all the crabs’ legs, then swallow the body whole, after which it will pick up the legs, one by one, wasting nothing!
Our spectacular morning was topped off by an encounter with a large pod of bottlenose dolphins, which we approached by lowering our Zodiacs and riding amongst them. The pod included mostly females, and some very young calves, many practicing their breaching in an endearing way.
Truly a day to celebrate, which we did during our cocktail on the sky deck while circumnavigating Roca Redonda, the remote remains of a once magnificent volcano, against the backdrop of a spectacular sunset.
