The goal of Science and the Sea is to convey this understanding of the sea and its myriad life forms to everyone, so that they, too, can fully appreciate this amazing resource.
For decades, whales in the Pacific Northwest were declining. Year after year, the populations kept getting smaller. In recent years, though, many of the whales have been coming back. Thanks to conservation efforts and legal protections, the numbers recorded by whale-watching organizations have been going up. In 2022, they even set some records.
Groups monitor populations in the Salish Sea—a narrow band that hugs the coast from central Washington to southern British Columbia. They add up eyewitness reports from commercial whale watchers and others.
Several species of whales inhabit the sea. The list includes humpbacks, grays, minkes, and a couple of varieties of killer whales—Bigg’s and southern residents.
Bigg’s killer whales were seen more often than any of the others—more than 1200 unique sightings. That’s an increase of more than 150 over 2021, and more than double the number in 2017. The jump is largely the result of a more bountiful food supply—seals, sea lions, porpoises, and even other whales. Estimates place the total population of Bigg’s whales at about 370.
Almost 400 humpbacks were seen—the largest number in more than a century. They were reported on more than 270 days—a big jump over the previous year.
And a group of critically endangered southern resident killer whales was recorded on 160 days—far more than average. So they, too, may be making a comeback—more whales for the Pacific Northwest.
The two largest ice sheets on Earth sit atop Antarctica and Greenland. But they’re both getting smaller in a hurry. They’re contributing to the rise in global sea level—about an inch over the past few decades. The rate at which the sheets vanish isn’t the same, though—Greenland’s is disappearing much faster.
The ice sheets can be hundreds of feet thick. But as the climate has warmed up, they’ve been shrinking. According to one study, from 1992 to 2020 they lost a combined eight trillion tons of ice, with Greenland contributing more than half of the total.
That’s a bit surprising, because the Antarctic sheet contains more than eight times as much ice as Greenland’s. But they’re disappearing for different reasons.
The Antarctic sheet disappears as shelves of ice that extend over the ocean break off and float away. That’s happening more often because changing winds are driving warmer water toward parts of the continent. As the icebergs move out, more ice glides from the land into the sea—raising the global sea level.
About half of Greenland’s ice loss is driven by the same process. But the other half comes from melting. Greenland has warmed up more than the rest of Earth—by about four degrees Fahrenheit in summer, and nine degrees in winter. Some of the water trickles to the bottom of the ice. It lubricates the rocks below, so the ice flows toward the ocean faster—contributing to the demise of Earth’s second-largest ice sheet, and the rise in global sea level.
Young sharks of several threatened species are living together in a “nursery” off the western tip of Africa. It’s one of the busiest nurseries in the Atlantic Ocean.
From 2016 to 2019, researchers counted the sharks found in fishing nets around Cabo Verde, a group of small volcanic islands about 350 miles west of Africa. They also interviewed most of the fishermen in the region to see where young sharks were most common. And one spot was by far the most popular: Sal Rei Bay, on the coast of Boa Vista Island.
The scientists confirmed populations of five species of shark there: milk, scalloped hammerhead, blacktip, Atlantic weasel, and nurse. All of the recorded species are fairly small. The juveniles spend several years in their nurseries before heading into the open ocean.
An international conservation group lists the Atlantic weasel shark as endangered, and the scalloped hammerhead as critically endangered. The other three species are “vulnerable”—they’re not facing extinction just yet, but they’re not in great shape, either. All five species are threatened by overfishing—in part because shark fins are still an expensive delicacy in some parts of the world.
Sal Rei Bay may be so popular among shark mamas and papas because it’s fairly small—less than 10 square miles—and it’s well protected from the ocean. It may provide plenty of food for the pups, along with protection from predators—a perfect nursery for young sharks.
Oil and gas bubble up through the ocean floor all the time. They form oil slicks, create tar balls that wash up on shore, and make pillows of methane ice. And in some rare instances, they form asphalt volcanoes—tall, black mounds with smooth sides.
The first were discovered in 2003, about two miles deep in the Gulf of Mexico. Others have been found in the Gulf since then, along with a few off the coasts of California and western Africa. Some of those in the Gulf of Mexico have split apart, creating shapes that look like the fronds of a palm lily, so they’re called tar lilies.
The volcanoes formed as thick oil percolated through cracks in the ocean floor. When it hit the cold ocean water, it turned solid, building the cones.
There are two fairly tall ones in California, about 10 miles offshore from Santa Barbara. The biggest is six stories tall and as wide as a football field. The volcanoes are about 700 feet below the ocean surface, though, so they weren’t discovered until 2007. They’re dormant today, although small vents of gas bubble around them.
A recent study looked at life around the larger Santa Barbara volcano. Scientists cataloged more than 40 species of fish, plus some corals and sponges. More than half of the fish living along the flanks of the volcano were rockfishes. Flatfish were seen around the structure, but not too close—perhaps because they’d be easy prey against the dark background: a rare asphalt volcano.
Otters and Wolves
Good news for one species isn’t necessarily good news for all. Consider the wildlife on Pleasant Island, off the coast of southeastern Alaska. Sea otters returned to the island a couple of decades ago. Gray wolves came along a decade later. The wolves ate most of the island’s deer, then started hunting the otters. That’s good for the wolves, but bad news for everyone else.
Fur hunters nearly wiped out otters in the region in the 18th and 19th centuries. But thanks to legal protections and conservation efforts, the population has rebounded. In fact, it’s about reached the maximum healthy number for both the otters and their habitat.
Gray wolves almost vanished, too, but they’ve also staged a comeback. Two of them apparently swam to Pleasant Island from the mainland in 2013, establishing a new pack.
Researchers began studying the wolves two years later. They watched the wolves in person, tracked them with GPS, and analyzed their poop to see what they’d been eating. In 2015, 75 percent of the wolves’ diet consisted of deer. By 2017, though, deer accounted for just seven percent. By then, sea otters accounted for more than half of their diet—the deer had all but vanished.
The researchers also saw that the wolves were actively hunting the otters—they developed tactics to surround the otters before they could escape to the ocean. So a success story for the sea otters might not stay that way—good news turned bad on a remote Alaskan island.
Millions of residents chased out of their homes. Trillions of dollars in extra damages. A tenth of coastal crops destroyed. That’s what some developing countries could face from coastal flooding by the year 2100, according to a recent study. Several regions could be especially hard hit, facing costs of more than five percent of their total economies.
Researchers looked at possible coastal flooding at 9,000 locations around the world. They forecast what could happen by the years 2050 and 2100 under worst-case forecasts, with temperatures climbing by up to seven degrees Fahrenheit. The higher temperatures will raise sea level, and could generate stronger cyclones with higher storm surges.
The researchers also considered whether countries could afford to protect themselves by building seawalls, improving drainage, planting mangrove forests, and taking other actions.
Without good countermeasures, the global cost of flood damage could add up to almost three percent of the worldwide economy. And the number of people flooded out could rise from 34 million in 2015 to 246 million in 2100. With good countermeasures, though, the impact could be limited to less than half of that.
Developed countries have the resources to protect themselves. But developing countries could face much more expensive futures. And the worst damage could be inflicted on the Nile Delta in Egypt and similar regions in western Africa and Asia—regions that can’t afford our warming climate.