The Changing Santa Barbara Channel
Whether It’s from Climate Change or Natural Cycles, Our Ocean Is Now Very Different
by Tyler Hayden | Published December 12, 2019
Sea horses in Goleta. Sea turtles at the islands. A whale shark in the sanctuary. Is our slice of South Coast ocean turning into a tropical coral reef? No, not by a long shot, but the Santa Barbara Channel is indeed changing.
Back in fall 2014, a dramatic and prolonged marine heat wave coined “The Blob” crept out of the Pacific and slowly spread along the West Coast. At the same time, a strong El Niño was gathering steam. It peaked in 2015 and eventually subsided in 2016, but the unusually high ocean temperatures brought on by these two extreme events never really went away.
The Santa Barbara Channel sits at a unique and life-rich transition zone, where cold water from Alaska meets warm water from the equator. Historically, it’s enjoyed a cool but comfortable average temperature of 16-17 degrees Celsius (or 60.8-62.6 degrees Fahrenheit). During the height of the Blob-El Niño anomaly, temperatures got as high as 22.5°C (72.5°F), and as recently as 2018 were hitting 21°C (69.8°F). While the overall average has levelled back out, it’s still 1-2°C above what it was before.
That would be significant for any ocean ecosystem, as a tick or two difference on the thermometer is enough to upset the delicate balance of food webs. But it’s especially dramatic for the Channel, because the threshold separating a coldwater fish environment from a warm one just happens to be 16.2°C, smack in the middle of our old temperature range.
Now that our average is higher, we’re seeing more and more warmwater fish make their way up from Baja California and San Diego to Santa Barbara. “Ever since the marine heat wave, species that we typically think of as warm species really took off,” said Ryan Freedman, a research operations specialist with the National Oceanic and Atmospheric Administration (NOAA). “It was pretty shocking at the onset, and then we didn’t see fish community change back. Usually after you get an El Niño, things shift back. But what’s out there doesn’t resemble the old community anymore.”
It’s not just fish. Scientists are seeing different types of birds, whales, sharks, urchins, and crabs out there — some only single sightings, others with much more regularity. “Although big ecological changes in response to climate change can be alarming,” said NOAA researcher Lindsey Peavey Reeves, “they present new opportunities for anyone — fishermen, kayakers, surfers — to encounter and appreciate new species.” However, there are real causes for concern in this warmer paradigm, she noted, like the massive die-off of sea stars and the disappearance of key kelp beds.
The seemingly obvious driver for all the newness, as Reeves pointed out, is climate change, though scientists are still trying to connect the dots. Observations are being logged and long-term studies are underway. The Channel is adapted to withstand a decent amount of variation, explained UCSB biologist Jenn Caselle. “But in my view and observation,” she went on, “these heat waves are not normal and are almost certainly determined by climate.”
Some older fishermen and scientists say they’ve seen this before. Stop panicking, they scold. Things will cool off. The kelp will come back. “I’m not sure they’re right,” Caselle cautioned. “We’re well outside the natural variation of the 40 years we have data for. This all has a very strong climate thumbprint on it. … Sea snakes down in Ventura? Hammerheads chasing fishermen out of the water? That’s just wackadoodle.”
So Long, Sea Stars; Hello, Urchins
Perhaps the most obvious and dramatic sign that the Santa Barbara Channel is different than it was even 10 years ago is the near-total disappearance of sea stars. In 2013, as waters were heating up, a mysterious and insidious disease started wiping out populations up and down the West Coast. “While sea star wasting syndrome (SSWS) has been around for decades, this most recent outbreak is unprecedented in scale and scope,” said UCSB marine biologist Carol Blanchette in a prepared statement.
The disease begins with lesions on the stars’ bodies and arms, which leads to limb loss and death. They essentially melt away. Hardest hit were ochre stars, the orange, red, and purple specimens we were used to seeing in tide pools. Sunflower sea stars in deeper waters were also killed off in massive quantities. This much-larger species, which can reach more than three feet in diameter and has between 16-24 limbs, feeds on urchins. Without them, urchin numbers — particularly the purple variety — have skyrocketed.
Urchins often feed on giant kelp holdfasts, which keep the long strands of leafy habitat anchored to the sea floor. As they munch through them, they create sandy deserts in their wake, where fish used to forage and crabs and snails used to live. “Historically, purple urchins have made barrens, but not as large and persistent as they are now,” said Kim Selkoe, a UCSB marine ecologist and director of the Commercial Fishermen of Santa Barbara. The purple urchin proliferation has also started to push out red urchins, the species that Santa Barbara is so famous for catching and exporting.
More than half of the 200 or so fishermen who launch every morning out of the city’s harbor are hunting reds. While their catches have gone down, Selkoe explained, prices have gone up, so they’re maintaining their living.
Selkoe is skeptical the population shift can solely be attributed to climate change, though she believes it plays a part. “The Channel is such a naturally dynamic place,” she said. “It’s hard to link what’s going on specifically to climate change.”
For instance, the Channel used to be jam-packed with barracuda back in the 1900s before they moved on. It was the same with albacore; they were common in the 1980s and then went away. Nowadays, normally rare bluefin tuna are being caught off Santa Barbara. Is that because of climate change, Selkoe wondered, or because their populations are rebounding after new protections? Or both?
Selkoe also made it a point to set apart what’s happening to the Channel’s kelp to the wholesale destruction in Northern California, where more than 90 percent of the aquatic forests are now gone. Our situation is not nearly as dire.
Nevertheless, some urchin divers are working to create a market for purple urchins, which could help keep their numbers in check. Stephanie Mutz and her partner Harry Liquornik have been catching purples (which are normally too small with too little roe to be eaten), fattening them up at an onshore abalone farm at Dos Pueblos Ranch, and then selling them to adventurous chefs in Santa Barbara, New York, and Los Angeles who covet their sweeter, creamier consistency.
Meanwhile, the spiny lobster market is booming as packs of the subtropical crustacean crawl north into the warmer Channel. Rockfish are doing well, too.
Rock crab is a different story. Their concentrations are on a downswing, which is part of their natural ebb and flow, “but climate change might disrupt that cycle,” said Selkoe.
That already seems to be happening to market squid, which are harder to catch these days. Selkoe also said she’s heard from a number of fishermen that there aren’t nearly as many clams and mussels around inshore areas. Without the bivalve mollusks filtering flecks and food and sediment out of the water, the visibility is much lower, they say.
Just Passing Through?
In recent years, a handful of especially rare species have poked their head into the Channel one or more times but haven’t been seen much since. Were they the forward scouts of an incoming population or just one-off appearances of lone individuals? Only time will tell.
Olive Ridley Sea Turtle
Santa Barbara fisherman Steve Escobar recently spotted and photographed an olive ridley sea turtle just outside the Channel Islands National Marine Sanctuary (CINMS) near Point Conception. “He told me the turtle looked to be in fine shape and not injured or unhealthy,” said NOAA’s Lindsey Peavey Reeves in an email. “Typically we would only see that species this far north if they were wayward or cold stunned, since they are a pantropical species. This is actually the population of sea turtle that I studied for my graduate work, and I thought now working at CINMS I would have to say goodbye to olive ridleys, but perhaps they are following me : ) More likely they are following marine heat waves and other warm water anomalies that seem to be occurring more and more frequently, meaning we may see more of these ‘tropical’ species in and around CINMS in years to come.”
Reeves’s team also recently saw a green sea turtle at Santa Barbara Island. It’s a rare species to encounter here, but now not abnormal, she explained, as their habitat has already shifted north with the warmer waters.
Ryan Freedman with NOAA said he received a credible report of a whale shark swimming through the sanctuary earlier this year. “It’s just extremely rare to see them here,” he said with the restrained excitement of a scientist. “It’s impressive they’re coming this far north so long after the warming trend.” Whale sharks are the largest fish in the ocean and can reach lengths of 40 feet or more. But fear not — they’re gentle filter feeders and mainly eat plankton.
Pacific seahorses normally only come as far north as San Diego; their southern range stretches all the way down to Peru. But a few were seen nestled in a seagrass bed in Goleta. Like all species of seahorses, females deposit hundreds of their eggs into what’s called the “brood pouch” of the male, where he fertilizes them. After 14 days of gestation, the male goes into labor and must force the young out of the pouch one at a time, which can take hours.
The largemouth blenny is a warmwater fish that was first observed north of Baja on the mainland coast in La Jolla in July 2015. It was also spotted in October 2015 at Catalina Island. It was first observed in Channel Island National Park waters off Santa Cruz Island on November 1, 2017. This sighting is the northernmost observation known to date and appears to be a range extension for this species.
Yellow-Bellied Sea Snake
This venomous reptile inhabits the coasts of Africa, Asia, Australia, Central America, and Mexico, including the Baja California Peninsula. It’s been found three times in Southern California since 2015. The last sighting before that was all the way back in 1972, during a particularly hot El Niño. The yellow-bellied sea snake is front-fanged and, like most other sea snakes, is capable of delivering an extremely potent bite.
Channel Islands National Park biologists conduct annual surveys throughout their jurisdiction’s kelp forest, intertidal, and coastal ecosystems. They’ve found three new species that appear to have taken up permanent residence there.
In 2013, the Channel Islands’ seabird monitoring program documented the first record of brown boobies in the park. This was a major northward expansion of their known range in the Gulf of California and along the Pacific coast of Mexico. In 2015, there was a dramatic rise in booby numbers in the Channel, with counts of more than 170 individuals at Santa Barbara Island. They attempted to nest there in 2017 with unknown success. On August 24, 2019, the park’s first documented hatching took place on the island.
Pelagic Red Crab
This species is typically found southwest of San Diego. In previous warmwater years, it was seen in the Channel but would stick around for only six months or less. Since June 2015, however, pelagic red crabs have been observed year-round on the north side of Santa Cruz Island.
Black Sea Urchin
During kelp forest surveys from 2000 to 2003, a handful of black sea urchins were observed at Santa Barbara and Anacapa Islands. A few more were seen in 2008, but then they weren’t seen again until 2015. Since then, they’ve been consistently spotted at Anacapa, Santa Barbara, and Santa Cruz islands. Park biologists have noticed a range in sizes and groupings of individuals, suggesting this species may be forming “small persistent populations.”
Back in a Big Way
These three biguns (and a small one) had all become quite scarce over the last couple of decades. Now they’ve returned, hopefully for good.
North Pacific Right Whale
Listed as endangered since 1970, the North Pacific right whale is the rarest of all large whale species and among the rarest of all marine mammals. Commercial whaling had depleted their numbers, and while hunting is no longer a threat, human activity such as entanglement in fishing gear, vessel strikes, and ocean noise are still major threats.
Once common, these bizarre-looking but harmless creatures had all but vanished from Santa Barbara waters for the last four decades until this April, when boaters suddenly started seeing them again. Second in size only to whale sharks, basking sharks can reach 30 feet long and feed with their big mouths agape on krill and plankton. No one knows why they’re back. “We’re not sure if it’s population recovery or if climate change is influencing where they go,” said Chris Lowe with CSU Long Beach’s Shark Lab. “We just don’t have the data yet.”
Giant Sea Bass
These behemoths are at the top of the kelp forest food chain. They can weigh up to 800 pounds, reach more than seven feet in length, and will eat anything they can fit in their gullets, including lobsters, rays, and small sharks. Overfishing brought their population to critically endangered levels, but protections passed in the 1980s helped reverse that. Researchers are now using the upswing opportunity to study the fish, since little is known about their biology and behavior. They’re using hydrophones to record the low-frequency grunts giant sea bass make when other large animals are around, including divers, to hopefully piece together the purpose behind the sounds.
Thirty years ago, black abalone could be found all over the Channel Islands’ intertidal zones. By 2009, their numbers had tanked so hard they were put on the Endangered Species List. But a recent study found new populations scattered throughout the sanctuary, whose populations seem to be growing at a nearly exponential rate. It’s still not clear what exactly is bringing the abalone back, or if they’re certain to remain.
Closer to Shore
Life in the Channel doesn’t start in deep water, or even in tide pools. It starts in that transformational belt between land and sea, in critically important salt marshes like the 230-acre UC-owned Carpinteria Salt Marsh Reserve. Hardly immune to climate-wrought changes, sea level rise is slowly shrinking its patches of dry land, where migrating birds such as sandpipers, sanderlings, willets, herons, and egrets need to land to rest and refuel.
“We’re already seeing lower number of those species overall,” said director Andrew Brooks, adding that coastal development and beach grooming elsewhere may be contributing to the decline. “It’s hard to tie it to one specific cause. But we know the numbers are down. That’s not a good thing.”
Brooks and his team are also keeping close tabs on the endangered salt marsh bird’s beak, a somewhat inconspicuous but cornerstone pollinator of the marsh ecosystem. Bird’s beak likes to grow in hummocks at slightly higher elevations. It soaks up fresh water when it rains and doesn’t have a high tolerance for saltwater. It dies under a rising sea.
The marsh’s clams, oysters, and mussels, on the other hand, don’t mind if they’re under three feet of water. But they’re now contending with the longer-term worry of ocean acidification, which weakens their shells. “We haven’t reached the tipping point where marine life can’t make shells,” Brooks explained. “But it may already require more energy. That affects their growth and fecundity — how many offspring they have.”
One positive change Brooks has noticed is the reappearance of osprey at the marsh. Heavily impacted by DDT, the species had faded from the area but started to crawl back over the last four to five years. A mating pair has taken up residence in the eastern portion of the marsh and is doing well, Brooks said.
He finished with a warning, however. Climate change skeptics like to bring up estimates that were proved wrong, Brooks said. That fosters doubt. But in most cases, the predictions were wrong because they were under-estimates. “Things are happening faster than we thought,” he said. “This is an issue we really need to tackle now. We may think we have 20 years when we really only have 10.”
Island Fish ‘Tropicalization’
Island Fish ‘Tropicalization’
It’s out at the western Channel Islands — Santa Rosa and San Miguel, specifically — where the “really massive” fish turnover is taking place, says UCSB’s Jenn Caselle. Historically, the waters around Santa Rosa and San Miguel were cooler than those surrounding Santa Cruz and Anacapa to the east. They were populated by dark-colored, cold-loving rockfish, señorita, and blacksmith that made their homes and hunting grounds among thick kelp forests.
Now, the observers say, with the higher temperatures, those western islands are starting to look a lot more like their eastern cousins, as warmer-water species like the richly colored garibaldi, sheepshead, and kelp bass move in. They haven’t pushed out the others, but as time goes on, researchers say, the losses of colder-water species are going to outpace the gains of warmer-water varieties. The process is called “tropicalization.” Kelp, which likes a cooler climate and has already been weakened by the warming, is also now being mowed down by runaway urchins.
Researchers say the losses of colder-water species are going to outpace the gains of warmer-water varieties.
This doesn’t necessarily spell doom and gloom for the islands. As ecosystems naturally change over time, certain plants and animals may insert themselves into the food chain without much disruption when other species migrate or die. But if new conditions arrive too quickly or with too much force, like in the case of the Blob-El Niño event, it can throw the fragile equilibrium out of whack. That’s what happened when the warming trend replaced high-calorie plankton with low-value zooplankton, which hurt small feeder fish like smelt and anchovy. When their numbers took a nosedive, it left the offspring of sea lions and sea birds hungry and stranded on beaches. NOAA’s Ryan Freedman described it as a “food-change mismatch.”
Looking ahead, Freedman said, regulators need to start thinking about climate change as a much more significant factor in the monitoring and management of marine protected areas (MPAs). When MPAs were first being mapped out in the early 2000s, he said, “climate change wasn’t nearly as loud or as pressing of an issue.”
MPAs have done an incredible amount of good in helping regions depleted of life recover their biomass, Freedman emphasized. But now serious resources need to go into gathering good, quantified data on how these areas are impacted by — and how they may be able to protect the rest of the ocean from — the effects of a changing climate. “Getting that published and in the hands of the state — that’s the next big effort,” he said.