Isla San Esteban
We started our investigations of the desert this morning in a sandy arroyo on Isla San Esteban. Nothing stands alone in the desert and that was immediately obvious as we found milkweed flowers being pollinated by an orange winged Pepsis wasp, commonly called “tarantula hawk,” shown in the picture above. As an adult these wasps are nectar feeders; they pollinate the milkweed flowers, which then depend on the wind to disseminate seeds borne on delicate parasols. The name tarantula hawk suggests further relationships. When she is ready to lay an egg the female wasp must find and paralyze a tarantula. The paralyzed tarantula is sealed in a burrow with the egg of the wasp. The wasp larvae will dine on the tarantula and then pupate. A new adult wasp emerges and the cycle continues.
As we explored further we found spiny-tailed iguanas draped over boulders, warming themselves in the morning sun. A little later, these same iguanas were found climbing the spine-cluster ladders of the massive Cardon cactus. The iguanas include the flower of the Cardon on their breakfast menu and several iguanas were observed munching placidly on the creamy white blossoms.
Back on the beach we found beautiful fat spirals of turbin shells, with smaller flattened spirals scattered about as well. These two treasures were found not to be two organisms, but two parts of the same. The smaller, flattened spiral is the operculum or the “trap door” that is attached to the foot of the snail living in the turbin.
In the early afternoon, we came across a feeding frenzy. A vortex seemed to suck the blue-footed and brown booby’s from the air and into the water. The waters churned with Common dolphins and a plentitude of scared fish, the fish being the base of this food chain. Or were they? The petrels were feeding on the plankton, the fish’s food so to speak.
A little later into the afternoon we sighted blows on the horizon, upon closer investigation we found them to be blue whales! Yes, blue whales, the largest animals on the planet, which we observed lunge feeding; their diet consisted of tiny planktonic krill.
A wasp, a flower, a tarantula, the wind, plankton, fish, birds, dolphins, and whales; a day full of discoveries in the web of life living in the Gulf of California.
We started our investigations of the desert this morning in a sandy arroyo on Isla San Esteban. Nothing stands alone in the desert and that was immediately obvious as we found milkweed flowers being pollinated by an orange winged Pepsis wasp, commonly called “tarantula hawk,” shown in the picture above. As an adult these wasps are nectar feeders; they pollinate the milkweed flowers, which then depend on the wind to disseminate seeds borne on delicate parasols. The name tarantula hawk suggests further relationships. When she is ready to lay an egg the female wasp must find and paralyze a tarantula. The paralyzed tarantula is sealed in a burrow with the egg of the wasp. The wasp larvae will dine on the tarantula and then pupate. A new adult wasp emerges and the cycle continues.
As we explored further we found spiny-tailed iguanas draped over boulders, warming themselves in the morning sun. A little later, these same iguanas were found climbing the spine-cluster ladders of the massive Cardon cactus. The iguanas include the flower of the Cardon on their breakfast menu and several iguanas were observed munching placidly on the creamy white blossoms.
Back on the beach we found beautiful fat spirals of turbin shells, with smaller flattened spirals scattered about as well. These two treasures were found not to be two organisms, but two parts of the same. The smaller, flattened spiral is the operculum or the “trap door” that is attached to the foot of the snail living in the turbin.
In the early afternoon, we came across a feeding frenzy. A vortex seemed to suck the blue-footed and brown booby’s from the air and into the water. The waters churned with Common dolphins and a plentitude of scared fish, the fish being the base of this food chain. Or were they? The petrels were feeding on the plankton, the fish’s food so to speak.
A little later into the afternoon we sighted blows on the horizon, upon closer investigation we found them to be blue whales! Yes, blue whales, the largest animals on the planet, which we observed lunge feeding; their diet consisted of tiny planktonic krill.
A wasp, a flower, a tarantula, the wind, plankton, fish, birds, dolphins, and whales; a day full of discoveries in the web of life living in the Gulf of California.
