Today’s article is about the Gulf of Santa Catalina, the marine life there, and how our knowledge of the marine life in the Gulf of Santa Catalina shows the need and opportunity to further study the world’s marine communities. The Gulf of Santa Catalina is a 100-square-mile area off the coast of southern California, located next to parts of the Los Angeles and San Diego metropolitan areas. The gulf’s western border is approximately defined by the Southern California Bight, an area of the Californian and Mexican coast, and the gulf’s western border is defined by an undersea area called Thirtymile Bank, and by Santa Catalina Island (Catalina Island) .
Catalina Island is a 75-square-mile island, 22 miles from the mainland. It has two towns, Avalon (Pop. 4,096) to the South and Two Harbors (Pop. About 200) to the North. About 75% of Catalina Island is open land owned by the Catalina Island Conservancy.
Even though the Gulf of Catalina borders on large cities and is often traversed by tourists, there is still a lot that we don’t know about the marine life and marine environment in the Gulf of Catalina. We have not done complete surveys of the species living in most parts of the Gulf. Big gaps also exist in what we think we know about the marine life in the Gulf. We do not know, for example, how climate change has affected, or will affect, which species live in the Gulf, or how much time they spend there. We also do not know how the changes that humans have made to mainland southern California’s landscapes and ecology, and to the ecology of other parts of the ocean, have affected the Gulf.
Catalina Island was formed from geological activity millions of years ago, but unlike most islands in the Pacific Ocean, Catalina Island was tilting downwards, not upwards. Catalina Island has ancient beaches far beneath the surf that we seek nowadays. Catalina Island used to have steep cliffs stepping up and back from the sea, but those are long gone, hidden far beneath the waves. Catalina Island is slowly tilting and sinking. The more the ocean rises, the more of Catalina Island is submerged. The fact that the parts of the ocean closest to Catalina Island contain submerged parts of the island affects the types of marine life that can reside in the Gulf of Catalina, and the “opportunities”, available to that marine life, including available nutrients, but also including other conditions like watercirculation, available sunlight, and temperatures.
Off the coast of Two Harbors, angel sharks have been spotted. A specific type of angel shark lives near Catalina Island. Catalina Island’s waters also have invasive species such as the seaweed Sargassum horneri. If you go to the beach along Catalina Island you will most likely see Sargassum horneriadorning the shoreline at Santa Catalina. This shows how the distribution of species in the ocean continues to change. Human intervention is part of this, but not the only part.
Blue Cavern Point Reserve, on Catalina Island was created near some caves. Not very much is known about Blue Cavern Point due to its depth and tumultuous terrain. In Blue Cavern Reserve, Looby, a U.S.C. undergraduate at the time, and Ginsburg, a U.S.C. professor found and made an inventory of all of the creatures that pass through or inhabit the conservation area year-round. Their study started in 2015, and they launched the study because nobody had previously catalogued all the species living in the Blue Cavern Point Reserve. They made numerous trips to the Blue Cavern Point Reserve to locate specimens, and also used other techniques, such as combing through old journals. Looby and Ginsburg’s study shows that systematic catalogues of the species living in other areas of the Gulf of Catalina, are also needed, because we do not necessarily know what species live in other areas of the Gulf of Catalina.
The Gulf of Catalina is a beautiful place to go snorkeling in, but astonishingly, parts of the Gulf of Catalina between Catalina Island and the mainland can reach up to 3,000 feet deep. The Gulf of Catalina has abundant sea life, which flourishes with nutrients that arrive there. Some of this sea lifeincludes kelp, spider crabs, yellowtail, octopi, and other creatures. However, we do not have knowledge of the habits of most of them, or how they respond to changes in environmental conditions.
Animals migrate in and out of the Catalina Gulf constantly. We don’t exactly know all of the species that pass through the Gulf of Catalina, when they inhabit the Gulf, or why they inhabit the Gulf. There are many undiscovered species that live in the Gulf of Catalina. The sheer depth and size of the Gulf of Catalina means that undiscovered species are likely to live there. We also probably do not know how the species living there interact with each other, or with their environment.
Natural climate change has always affected the ocean, and today, global warming is changing our oceans at a faster rate, and much of the sea life that we could have seen about 5-10 years ago has migrated. Much of the sea floor of the Gulf of Catalina is unexplored and uncharted. Many shipwrecks lie in the gulf. Unfortunately, we know little to nothing about the exact location of most of these. We know little to nothing about their location, and we don’t know most of their stories either.
Looby and Ginsburg’s study was astonishing, but new technologies can help researchers to get a more thorough picture of the species distribution in an area, including species that are rare in the area, by monitoring the area continually with cameras. Looby and Ginsburg’s method can be improved upon through use of additional technologies, such as installation of undersea cameras that can monitor parts of the Gulf for a long period. These cameras can monitor how marine species interact with each other, and with the rest of their environment, over a long period, and can also monitor whether some species appear in parts of the Gulf for part of the year, and then move elsewhere for the rest of the year. This will provide a fuller picture of the Gulf’s biodiversity and how it is changing in response to climate change and other factors. There is a need for multiple research projects further studying the marine life in the Gulf of Catalina, and also studying the habits of the species there, over time, and how they are affected by changes in climate and other conditions such as salinity, water currents, and presence of nutrients.
One of the metropolitan areas along the Gulf of Catalina is Los Angeles, California (Pop: More than 15,000,000). Los Angeles produces lots of waste, especially plastic and cigarette butts. These unfortunately affect the Gulf of Catalina and Catalina Island’s waters. The Gulf of Catalina’s waters are currently being polluted in other ways by California’s coastal cities. Not only that, but in previous decades we threw many barrels of DDT and DDT products into the Gulf of Catalina, terrorizing the environment and hurting the ecosystem. The effects of this pollution are currently unclear, and might change over time, but must be monitored. By scanning the Gulf of Catalina’s floor with cameras, we may be able to find the DDT barrels, and hopefully remove them. We may also better understand how the DDT and other pollution affects marine life in the Gulf of Catalina by deploying cameras in the Gulf, especially in locations near the pollution dumping sites, and monitoring the footage the cameras produce over a long period of time.
Conclusion
The Gulf of Catalina is home to many interesting creatures and many interesting chemicals. Researchers are always working their hardest to better our knowledge of this interesting gulf in the Pacific Ocean. However, there is much that humanity still does not know about the Gulf of Catalina, and we should continue studying the Gulf, and use new methods to study it, to protect the species there and to use any opportunities for humanity that might be present in the Gulf of Catalina.
References:
Life History Traits of the Invasive Seaweed Sargassum Horneri at Santa Catalina Island, California, Aquatic Invasions (2018) Volume 13, Issue 3: 339–350.
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