A First Wetting with the Coming El Niño in the Galápagos IslandsMarkes E. Johnson
Markes E. Johnson
Island time includes the normal passage of life functions for a local biota in response to the daily rhythms of sun, moon, and tides as well as to the disruptions caused by big storms or other perturbances under extreme El Niño conditions. For paleontologists looking back in geologic time, it is possible to find evidence of these ebbs and flows preserved on the rocky shores of a 199-million-year-old island in the Saint David’s Archipelago of southern Wales.[i] Combing through the rocks exposed alongside the Bristol Channel, we can sense those last moments of normalcy for Jurassic limpets, oysters, and rock-encrusting corals before they were abruptly buried under stony rubble deposited by a massive hurricane. During the Jurassic, pterodactyls nested on those same islands. Those in my profession appreciate these rare opportunities, much like how ecologists witness similar disturbances in real time on islands today.
Such events in ecological time, both normal and catastrophic, still play out in one of the world’s most extraordinary settings: the Galápagos Islands, located 600 miles off the coast of Ecuador. It has been my good fortune to visit this archipelago on several occasions, always during fair weather when life was unaffected by the violence of storms. The normalcy of island animals going about daily life completely oblivious to human visitors in close contact is without parallel. Among Charles Darwin’s observations during his own visit to the islands in 1835 was the ease with which birds could be approached at their roosts and knocked from tree branches to the ground with the butt of a rifle. Before my first visit in 2009, it never occurred to me that I would join even the most amateurish of bird-watchers who are privileged to only look and take photos.
None were more striking than the male frigate birds that competed with one another by inflating their bright-red gullet pouches to attract a mate to their ridiculously simple nests formed on the ground with only a few twigs.
My aversion to ornithology arose during childhood, when I was compelled to accompany my father on the biennial Audubon bird census in eastern Iowa on the Upper Mississippi River. The dedicated birders in our group knew each bird by song and could pick out their perches in high trees with uncanny alacrity. What I did not know at the time was that I was terribly near-sighted and in need of glasses. Long after my father’s passing, I had the chance to put together a semester-long geology course at Williams College on the Galápagos Islands that included a visit during spring break. I anticipated the geology, but I was unprepared for the thrill of visiting the crowded nesting grounds on Genovesa Island in the northern part of the archipelago. A dizzying array of bird species, like the colorful blue-footed and red-footed boobies, were in the midst of their breading season. None were more striking than the male frigate birds that competed with one another by inflating their bright-red gullet pouches to attract a mate to their ridiculously simple nests formed on the ground with only a few twigs.
Visiting Española Island another year in the southern part of the archipelago, I was treated to the spectacle of the courtship dances performed by waved albatrosses (Phoebastria irrorate), accompanied by head-nodding and the loud clacking of their long beaks striking each other like dueling swordsmen. Among the largest birds in the islands, with wingspans up to 8 feet, adult albatrosses require a long runway in order to launch from cliffs for take-off on feeding runs. It may have been the same for the ungainly pterodactyls during the Jurassic. The mating season was well advanced; albatross chicks lay hidden in the underbrush, waiting for parents to return with food. Unlike other hatchling species that grow up to dwell permanently in the Galápagos, each new generation of albatross fledglings leaves the colony to spend the next six years at sea. I thought of my father and how he would savor such an encounter at just the right place and just the right time.
In March 2023, on our way to the Plaza Islands for an excursion , a crew member showed me a news story on his iPhone about the havoc caused by Cyclone Yaku off the coast of Peru. The Peruvian National Meteorological Service reported the storm as having a greater intensity than previous El Niño disturbances in 1998 and 1983. A light rain began to fall during lunch time and we feared that the outer band of the storm was on track to brush the Galápagos. South Plaza Island is formed by basalt layers that rise on a gentle incline from the sea on one side to end with cliffs that plunge 80 feet back into the sea on the other. The adjacent North Plaza Island also exhibits sea cliffs we could see when we anchored our vessel in the strait. Our visit to South Plaza was announced as a dry landing yet a steady rain came down when we stepped ashore. My sneakers were soaked soon after I began the ascent to the top of the island. Stately cactus trees (Opuntia galapageia) lined the route to the crest, and the flow of rainwater descending the pathway already had turned into a torrent. Pausing at the top, we observed swallow-tailed gulls (Creagrus furcatus) in erratic flight above their nests in the cliffs below.
The path continued along the island’s crest until it reached a more open spot, where dozens of cactus-tree seedlings had been planted. Each was enclosed by a wire cage to protect the young plants from browsing by native land iguanas. Our guide explained that he had volunteered to help re-establish the plants after heavy rains during the last El Niño washed out the slope on this part of the island. Undisturbed, a cactus tree may grow to a height of 10 or 15 feet, but the plant’s root system is shallow and prone to failure in strong winds and heavy rain.
Instead of descending straight down to the shore, the path followed a diagonal route toward our landing place. Astride the path, Nazca boobies (Sula granti) sat on ground nests, water rising around their tail feathers. We soon encountered the first of several eggs that had rolled onto the trail, dislodged from rudimentary nests by the rush of flowing water. Our naturalist picked one up and placed it in a more secure spot on a cover of Galápagos carpet weed (Sesuvium), where the parent bird might have a chance to find it. We paused again when we saw a cracked egg on the path. Looking over our guide’s shoulder, I could see that the embryo was barely developed; it would have required a much longer brood time to become a hatchling. We were still immersed in ecologic time, experiencing a significant disruption to the local flora and fauna that threatened to set things back by a generation or more.
My last bit of dry clothing was soaked through by the time we got back to the ship. Once on board, I was astounded to see a series of waterfalls cascading off the upper lip of North Plaza and plunging down the vertical rock face. Several waterfalls were muddy brown, except for one that flowed red. I surmised that the crest of North Plaza formed a wider plateau where water had ponded to fill a series of depressions before spilling over the edge of the cliff. One of those depressions was undoubtedly less vegetated and likely lined with red clay. Our ship’s crew had rarely witnessed such a sight and many were busy taking photos.
The next morning, the sky was blue and the weather was good for our departure from the airfield on Baltra Island. Checking news reports at home, I learned that Cyclone Yaku had spawned from an unusually low-pressure atmospheric system. Large parts of coastal Peru and Ecuador were flooded, affecting 49,000 people and destroying thousands of homes. The cactus trees and nesting birds on South Plaza in the Galápagos Islands experienced none of that, but their home was likewise disturbed in a fleeting moment of ecologic time. The question on forecasters’ minds is whether or not Yaku was the opening salvo in the next siege of a heightened El Niño season, and whether this El Niño would bring yet more devastation to the region and beyond, all part of ongoing global warming.
Markes E. Johnson is the Charles L. MacMillan Professor of Natural Science Emeritus at Williams College, and the author of Islands in Deep Time: Ancient Landscapes Lost and Found.