When orcas and white sharks cross paths, only one can prevail as the true apex predator. New research from the Monterey Bay Aquarium published in Nature Scientific Reports details these rare, sometimes brutal encounters — and their ecological implications.
It’s a study decades in the making because observations of the two creatures interacting is a rarity.
Scot Anderson, a white shark expert and seasonal researcher for the Aquarium, still remembers one such run-in more than 20 years ago near the Farallon Islands, a short boat ride west of downtown San Francisco.
“The first time it happened was kind of shocking to everybody,” Scot says. “Before we had seen anything like that, people would ask, who’s the baddest predator?”
The first scorecard came on October 4, 1997, when orcas killed and partially ate a white shark within view of a whale-watching boat. Scot was heading out from nearby Bolinas when he heard what was happening over the radio.
In the coastal habitats of Baja California, life thrives on the edge of desert sands and sapphire seas. Our newest special exhibition, ¡Viva Baja! Life on the Edge, opened on March 19, featuring the incredible creatures and habitats of this narrow Mexican peninsula.
But we’re not just exhibiting the splendors of Baja’s rugged 800-mile coastline. We’re also taking a lead role, working with colleagues here and in Mexico, to safeguard it.
Close ties with Mexican researchers
The Aquarium works with several universities in Baja—including El Centro Interdisciplinario de Ciencias Marinas (CICIMAR) and Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE)—to study key marine species, such as white sharks and and mahi-mahi (also known as dorado).
“There’s been this growth in how we approach other countries and also meet our needs as an aquarium,” says John O’Sullivan, the Aquarium’s director of collections
We’ve been tagging juvenile white sharks in Southern California since 2002, documenting seasonal migrations of these young fish between coastal waters in the United States and those on Baja’s Pacific coast.
Through September 2, Monterey Bay Aquarium and Monterey Bay National Marine Sanctuary will host Big Blue Live – an unprecedented series of live natural history broadcasts from PBS and the BBC. Big Blue Live highlights the remarkable marine life that gathers in Monterey Bay each summer, and celebrates an ocean conservation success story of global significance. We’re publishing guest commentaries about conservation efforts that contribute to the health of the bay and our ocean planet. This is from Sanctuary Superintendent Paul Michel.
Recent NASA pictures of Earth remind us that we indeed inhabit a blue planet – that most of our planet is covered by the ocean. In fact, it is the “big blue” that makes ours a habitable place to live, regulating temperature and weather, and providing more than half of the world’s oxygen. So it’s fitting that Big Blue Live comes here to showcase one of the most spectacular ocean environments on Earth.
The ocean is home to amazing creatures, from microscopic to gigantic – seemingly endless varieties of the shelled, scaled, skinned, feathered and furred. But, when you consider all the marine ecosystems, all the coastlines around the continents, even all the aggregations and migrations of sea life, Monterey Bay National Marine Sanctuary stands out as one of the most spectacular: beautiful, rich, and diverse. As a result, this Sanctuary offers some of the best marine wildlife watching in the world, and is often described as the “Serengeti of the Sea”.
What makes this place so special is what happens out of sight and behind the curtain of waves. Seasonal winds drive cold water to the surface from great depths. These waters are rich in nutrients, which fuel the growth of phytoplankton – the basis for the Sanctuary’s rich marine food web. This productivity invites animals from all corners of the Pacific to come and dine (and live year-round) at the “Monterey Bay Café”!
And what’s on the menu? There are some tasty entrees: krill, squid, sardines, anchovies and even jellyfish (if you’re a leatherback sea turtle!). All told, 34 species of marine mammals and more than 180 species of seabirds and shorebirds come to the table. Monterey Bay and Greater Farallones sanctuaries together contain the largest concentration of white sharks on the west coast.
We humans feed here as well. Since 1992, the sanctuary’s productive ecosystem has supported the harvest of more than a billion pounds of sardines, anchovies and squid. Last year was the greatest landing (by weight) of any of these prey species in the past 15 years, with 90 million pounds of squid alone landed at local ports.
Along with krill (which are not fished) these are the most significant prey in the ecosystem, upon which many species from whales to salmon to seabirds to halibut rely.
Monterey Bay and surrounding waters are also special because of the protection they’ve received. Designated in 1992, Monterey Bay National Marine Sanctuary is a federally protected marine area, an underwater equivalent to the grandest of America’s national parks. Stretching from Marin County to Cambria, the Sanctuary encompasses a shoreline length of 276 miles (more than one-quarter of the California coast) and 4,602 square nautical miles of ocean. The Sanctuary plays an important role in protecting marine life and ecosystems of the Bay, as well as conducting scientific study and raising awareness about what a special place it is.
Overall, the marine habitats and living resources in Monterey Bay National Marine Sanctuary are in excellent condition, according to our latest evaluation of current trends and pressures. Populations of humpback whales, blue whales, gray whales, elephant seals, sea otters and numerous fish species are stable or slightly increasing.
As one example, elephant seal births in the Sanctuary have more than tripled since 1992. In fact, there were no births at Piedras Blancas, near the south end of the Sanctuary, in 1992. Today, a large well-established colony exists, producing thousands of births. For another, best estimates put the Eastern Pacific population of gray whales at a healthy 20,990 individuals at the end of 2014. Gray whales make one of the longest annual migrations of any mammal: they travel about 10,000 miles (16,000 km) round trip!
Over the last two years, humpback whales (about 1,875 individuals in the West Coast stock) have been seen close to shore and very accessible to the whale-watching public as the whales feed on anchovies and krill. Monterey Bay National Marine Sanctuary led the way in protecting krill as a critical component of the ocean food web. This is now a regulation for the entire west coast of the U.S.
To see animals like these in the wild is truly the experience of a lifetime. Because they’re ocean dwellers, and often below the surface, most of us rarely get the chance. Big Blue Live will deliver these experiences to people across the planet in a very engaging and special way.