The western and northern sections of the Solstice's circumnavigation of Australia were full of sea days, which provided a lot of opportunity to appreciate how the sea conditions change steadily with latitude and longitude here. From the productive shelf waters of South Australia teeming with dolphins, the influence of the Leeuwin Current that brings warm surface water from the Coral Sea all the way through the Torres Strait and along Northwestern Australia became quickly apparent as we approached the Western Australia coastline.
As we traveled North, so did the outside temperature and humidity. The color of the ocean and nature of the creatures in it also changed to reflect the lack of productivity relative to the waters we'd been sailing in previously. We left pods of oceanic dolphins behind to be greeted by endless congregations of large pelagic jellies. With less food readily available on the sea surface, the marine life that thrives in the open water offshore must be creative. Among those that don't conform to the 'normal' predator prey relationships are jellies amd sea turtles. It's almost comical to watch a turtle's slow approach, and the subsequent bellyflop style ambush of a nearby jelly.
Bypassing Bali due to security concerns, we had to make a technical stop at Willis Island, a weather monitoring station in the Coral Sea outside of the Great Barrier Reef. What was perhaps an inconvenience for some became a treat for many of us who thoroughly enjoyed watching the way the most common residents of the island and surrounding sand cays make a living. Large flocks of Red-footed, Brown, and Masked Boobies put on an exciting show of plunge diving toward the surface of the water all around us before, during, and after our visit. Usually boobies (like gannets) will capture their fish prey beneath the surface, but here their prey required a unique strategy, as their primary targets were yet another oddly adapted marine animal: flying fish. It was both exciting and ironic to watch a bird lock eyes onto a fish in flight, swoop down dramatically, and chase the fish above the surface as the fish skid erratically across it. If one bird took the plunge, several more would follow with much commotion, usually resulting in an unsuccessful collision of feathers and splashing. But just often enough, a bird would be agile enough to catch the fish at just the right angle to swallow before the fish could disappear back beneath the surface.
Of all life on earth, marine creatures seem to have developed some of the most diverse and extreme strategies for finding and acquiring enough food to survive. Observing some of the strangest of these, one can really begin to appreciate the wonderfully complex food web that is the ocean.