August 9, 2012
The Bat Ray: A terrifying creature indeed
By Nathan Chen
So this Monday marked my first official swim in the ocean, (and by that I mean with goggles and actually swimming; don’t worry I’ve been in the ocean before) and call it corny but it taught me some things. For starters, I’m pretty wimpy when it comes to being alone in the water. Be it too many shark week episodes where the lone man gets dragged underwater by some unseen entity, or past stigmas by my over cautious parents who themselves were never too big on water, there is just something scary about putting half my body into something that is cold, dark, and full of other creatures that have bigger teeth than I do. That said, when I finally decided to man up and start actually swimming (rather than cowering by the dock and staring at my feet in the dark) I began to explore the sea life around me.
One of the first significantly freaky things I saw was a bat ray laying half buried on the bottom of the sand. Now I know (rather I was told while frantically flailing my arms to get out of dodge) that bat rays aren’t exactly the kind of species one should necessarily be afraid of, but it was either its eerie shape or just the fact that it was laying half buried (obviously waiting to eat me whole) that made me swim back to shore with more motivation than I otherwise would have. Today, sitting at a dry desk with my feet on solid ground I decided to learn more about the bat ray, so that in the future when we go snorkeling I can at least pretend to not be such a wimp.
The bat ray is a bottom dweller, living on mud bottoms at depths up to 50m. (1) They have flattened triangular bodies that are wider than they are long, as well as a long tail studded with up to 5 poisonous spines. (2) If this doesn’t sound scary enough to an inexperienced ocean visitor as myself, the bat ray can grow to 6 feet in width and weigh over 200 pounds. (1) Add to that its ability to live and breath underwater, and that’s already 5 distinct advantages it has on me.
Luckily however, the bat ray doesn’t feed on humans, nor does it spend its days hunting for people to torment them with its poisonous spines- instead it feeds on small bony fishes, worms, abalone, and small crabs. The bat ray also remains solitary for the most part, sticking to itself unless mating or feeding- which is lucky for me since I can just avoid one instead of five.
Perhaps the most interesting fact about the bat ray however, is its adaptive camouflage abilities. From a birds eye perspective, the bat ray blends into the dark ocean floor, but to a fish below the bat ray, all that is seen is light coming in from the surface. This camouflage ability makes it hard for the bat ray to be attacked by any potential predator, and makes it easier for them to catch unsuspecting prey. Unbeknownst to them however, the paranoid human eye can detect its presence even from distances natural predators may not be able to, though at least this body of that eye knows to keep a safe length away – I obviously just don’t want to scare it.
About the author: Nathan Chen is a second year Environmental Studies major with a minor in business. His passions are found on dry land, in physical activities where he knows where the other half of his body is.
The Value of Ecosystem Services
By Scott Lindemann
I was hiking along a ridge near the Wrigley Institute here on Catalina Island when I remarked to a friend “It’s been too long since I’ve seen stars.” But it has taken nearly a day for the full implication of my comment to sink in. It has been too long since I’ve seen the stars. Seeing those stars fulfilled a need I didn’t even know I had, and in my opinion, seeing the grandeur that nature has to offer fulfills a subconscious “spiritual” need for all humans.
Others have recognized this human desire for natural beauty as well. Perhaps since the dawn of human culture, nature has been a source of inspiration for artists, philosophers, and leaders of men, offering spiritual and intellectual fulfillment for the human soul. Interestingly enough, these services are referred to as “cultural services,” and are a recognized type of service that natural areas can provide to humans. Other types of services include “provisioning services” such as providing food, “regulating services” such as purifying water as it infiltrates into aquifers.
Despite these services, it seems to me that the implicit value of wilderness is hardly recognized by American culture. Prior to studying at USC, I viewed undeveloped land as simply empty space to be built on, void of any real value. While I appreciated the beauty of the great outdoors, I had no idea of the valuable and very real services that an undisturbed ecosystem could provide for humans. For instance, the Tongva people native to Catalina were able to use the environment for food, water, and soapstone. Today, marine kelp forests sequester carbon and terrestrial Catalina Cherry trees provide food for foxes and birds as well as the occasional curious human. Riparian soil, along with the plants and microorganisms living in it, cleans water as it flows into the ocean.
In my opinion, humans should place more value on these “valueless” services that ecosystems provide, and should think twice before developing undisturbed areas of land. The human population is growing, and it is important to preserve these areas of wilderness while they are still available. I for one am thankful that the area around the Catalina Island Wrigley Institute has been set aside as a Marine Protected Area, as well as being protected by the Catalina Island Conservancy. It is amazing to have such an undisturbed area of wilderness to pause, reflect on what is truly important in life, and to rejuvenate myself among the grandeur that is freely provided by this island along with its more practical services.
About the author: Scott Lindemann is a fourth year student at the University of Southern California. He enjoys reading, cooking, and lifting weights.
This Year Could Be the Last for Underwater Habitats
By Katherine Moreno
A trend emerged in the 1960s spawning the construction of over forty sea floor laboratories, or “habitats,” in the U.S. and other countries around the world (Walsh 48). The laboratories, maintaining the same pressure inside as the sea outside, provided a means for marine biologists to conduct lengthy underwater research without having to go through the time-consuming process of decompressing every time they leave the water (Bell). Today, the Aquarius 2000 (called Aquarius prior to 1997) is the only operational sea floor laboratory in the world (Walsh 48).
Constructed in the 1980s and funded by the National Oceanic and Atmosphere Administration (NOAA), the Aquarius was originally supposed to be located at the USC Catalina Marine Science Center (CMSC) on Catalina Island. It was planned that the lab would be placed next to the island’s giant kelp forest (Walsh 49). However, USC’s marine science program changed direction, and the NOAA decided to move the underwater lab to the U.S. Virgin Islands (Walsh 49). Following 1989’s Hurricane Hugo, the Aquarius was repaired and then moved to its final home in the Florida Keys National Marine Sanctuary, adjacent to the Conch Reef, where it has been used for a variety of purposes, from coral reef research to astronaut training (Allen).
Underwater research laboratories are particularly useful when located near sea-floor features that make good sites for studies that occur over long periods of time and are not disrupted by the comings and goings of researchers, such as the Catalina Island kelp forest and the Conch Reef coral reef. However, the high cost of underwater habitats relative to the cost of conventional methods of working from a research vessel and using SCUBA gear, combined with the fact that sea floor laboratories are fixed in location and limit research opportunities to a specific site, has led to the decline of such facilities (Walsh 49). Even the future of the Aquarius 2000 is now in jeopardy—the Obama administration recently eliminated funding for the facility, which will force it to shut down if its staff is unable to find another way to fund the laboratory’s three million dollar annual budget (Allen).
Marine researchers are currently fighting to prove that the Aquarius 2000 is worth saving. Tom Potts, director of the facility, says divers at the lab get about “ten times the productivity over diving from the surface” (Allen). Sylvia Earle, former chief scientist for the NOAA, says underwater laboratories offer “the gift of time;” researchers get a different perspective when they can observe a fish for hours and hours without having to leave the water (Allen). Mark Patterson, a professor at the College of William and Mary, says the lab allows scientists “to conduct measurements and experiments using delicate instruments, something not possible on a two-hour dive” (Allen).
The loss of the last underwater research habitat would deprive marine researchers of the only existing facility that allows them to conduct long-term underwater studies. Hopefully the Aquarius 2000 will get the funding it needs and we will avoid losing such a unique and valuable resource.
Sources Cited:
Allen, Greg. “With Funding Gone, Last Undersea Lab Could Surface.” NPR, 17 July 2012. Web. 7 Aug. 2012.
Bell, Peter M. “Underwater lab.” Eos Trans. AGU 64.36 (1983): 537. Web. 7 Aug. 2012
Walsh, Don. “Several firsts and a final farewell.” Sea Power (1998): 41-49. ProQuest. PDF file.
About the author: Katherine Moreno is a senior working toward a bachelor’s degree in environmental studies at USC Dana and David Dornsife College of Letters, Arts and Sciences.
Happy Fish, Happy People: Keeping Marine Ecosystems Healthy Comes Full Circle
By Richelle Tanner
As I’ve lived my whole life on the coast, seeing marine life a stone’s throw away from the shore is no surprise to me, in fact, I’ve come to expect it. The plethora of wildlife that I take for granted would not be there if not for the various environmental regulations imposed by authorities such as (on the federal level) the Magnuson-Stevens Fishery Conservation and Management Act, the Endangered Species Act, the Coastal Zone Management Act, the National Marine Sanctuaries Act, the National Wildlife Refuge System Administration Act, and the National Park Service Organic Act, among many others. Over-fishing and water pollution are major contributors to the decline of marine biodiversity; one way these effects can be stifled is with the installation of a Marine Protected Area (MPA).
A prime example of a successful MPA is on Catalina Island, CA around the USC Wrigley Institute For Environmental Studies. In my short time here, the quantity and diversity of marine life that I’ve seen while snorkeling is unparalleled — where else can one stumble upon 30+ enormous bat rays and leopard sharks practically on top of each other on the sandy bottom just off the shore? For anyone witnessing this firsthand, it can be hard to fathom that the effectiveness of MPAs is being questioned within the scientific community. Granted, the impact on intertidal zones rather than areas beyond the littoral zone garners more concern, however, it is applicable to all MPAs’ regions. An exemplary concern is the act of illegally harvesting prohibited species in easily accessible zones. This undermines the intentions of the MPAs, as the restrictions on harvesting species and disturbing marine species and habitats are in place to protect healthy biodiversity from human influences. To read more about the value of MPAs, click here.
In a MPA, certain restrictions for pollution, interaction, and harvesting are imposed in order to preserve the natural marine habitat. For example, around Catalina Island, boats are not allowed to drop anchor, the harvest of shellfish is prohibited, and only certain coastal pelagic species are available for harvest, among countless other regulations regarding pollution. In addition, there are regulations on land uses, as certain practices in maintaining soil health can impact nearby marine ecosystems. Nitrogen fixation and denitrification are issues normally associated with soil and agriculture, however, runoff from excessive fertilization can offset the natural balance in an ecosystem (in this case, a marine ecosystem). This can indirectly lead to nutrient pollution and/or dead zones, which marine ecosystems are protected against when they become MPAs. Also in the case of the Wrigley Institute on Catalina, certain herbicides cannot be used on invasive species such as fennel, since the runoff would eventually make its way to the MPA and contaminate it. This type of marine conservation is one of the more effective methods, as it is preventative rather than restorative (after the damage has been done). For example, it is infinitely better for an oil spill to be prevented than even the best, least intrusive clean-up of an oil spill. Similarly, it is easier to protect biodiversity and pristine habitats than to try to recreate them after allowing ecosystem decay due to anthropogenic influences.
As with any ecosystem, humans are as much a part of it as any other organisms. Not only can we negatively influence it with pollution and overuse, or positively influence it (or at least protect it from our own harmful ways) with protection laws, but the ecosystem can affect us accordingly with its overall health. Climate change is inevitably a factor in the health of an ecosystem, and its impact on MPAs is a factor in their effectiveness. Climate change is both influenced by humans and can influence human activities; it exemplifies the “full circle” relationship that we have with our surrounding ecosystems. In establishing more MPAs and similar programs, humans will benefit because healthy ecosystems are more efficient and preserve more natural biodiversity, slowing the growing effects of anthropogenic influences on the world, one reserve at a time. Although the trade-off for a clean, healthy MPA involves relinquishing economic benefits and coastal transportation conveniences, it is worth it. With a growing population and increasing anthropogenic influences on the environment in our future, MPAs are an essential part of preserving biodiversity and healthy marine ecosystems for years to come.
http://www.mpa.gov/resources/faqs/
http://www.springerlink.com.libproxy.usc.edu/content/017187002nt71191/fulltext.html
http://www.sciencedirect.com.libproxy.usc.edu/science/article/pii/S0964569110000037
About the author: Richelle Tanner is a sophomore in the USC Dornsife College and the USC Thornton School of Music pursuing a double degree in Environmental Studies, B.S., and Jazz Studies, B.M.. She intends to pursue graduate studies in Marine Science and originally is from Seattle, WA.
Santa Catalina: the Bison’s Makeshift Home
By: Lauren Stoneburner
Santa Catalina Island—a coastal Mediterranean island off the coast of California—is the least likely place to find America’s quintessential prairie animal, the American Bison (Bison bison). However, the filming of a Western movie in 1924 summoned these beasts from the grasslands of central North America to this isolated island, which they have come to call “home.”
As residents and tourists grew accustomed to their presence, they became an iconic feature on the islands. More than one million tourists visit Catalina Island every year, and many of those tourists come specifically to see the bison (Trivedi). The bison has not only brought revenue to Catalina’s economy, but residents have adopted a sense of pride over these animals, contributing to the island’s culture (Sweitzer). The economic and cultural value that these beloved animals provide has protected the species from being completely eradicated. However, their numbers must be limited, for their impact on the native island ecosystem is undeniable.
Because of its long-term isolation, Santa Catalina has developed an intricate ecosystem, composed of specialized species that play very specific roles within the ecosystem. Prior to the bison’s arrival, Santa Catalina had never before hosted large, grazing ungulates (Sweitzer), so their presence has greatly disturbed the dynamics of this fragile ecosystem. The bison’s primary impacts stem from their grazing, trampling, and wallowing behavior.
Catalina’s bison currently graze on a variety of native and non-native vegetation. Though they primarily eat grasses and forbs, they have added to their diets cactus and some woody schrubs, including the endemic coastal scrub oak (Sweitzer). Thus, bison do control the exotic species populations through grazing, but they directly limit the success of native plants as well. In total, the pressure that bison have put on native plants is far greater than the benefit of their controlling invasive competitors (Sweitzer).
Additionally, bison wallowing has also promoted the spread of invasive plants. As bison wallow, they embed plant seeds into their fur and later release the seeds into the environment as they wallow elsewhere. This behavior directly spreads non-native seeds across the island, allowing the plants to establish populations in new regions and further outcompete native species (Sweitzer). These impacts can be reduced by limiting the bison population size, for fewer bison directly lessens non-native plant dispersal (Sweitzer).
Trampling, along with grazing and wallowing, causes the worst damage—soil degradation. These behaviors kill the vegetation, which hold the soil in place. As a result, the soil becomes loose and exposed, leaving it vulnerable to erosion (Trivedi). Erosion washes away fertile soil, transporting critical nutrients, such as nitrogen and phosphorus needed for plant growth, and microorganisms living in the soil that perform ecosystem functions, such as nitrification, decomposition of dead organics, and recycling of other nutrients. Thus, the impact that bison have on soil quality is catastrophic, for the soil ecosystem is lost and no longer provides nutrients that native plants need to support the rest of the ecosystem. This provides further opportunities for invasive plant species with less specified soil requirements.
The Catalina Island Conservancy manages the bison herd size, keeping the population between 150 and 200 individuals (“History”). This status quo compromises the environmental integrity of the island and the cultural and economic pressures. Considering how strongly attached the residents and tourists are to the American bison, it is not currently feasible that the bison will be entirely eradicated. However, the current status quo still sacrifices more environmental integrity than should be allowed.
Catalina Island holds an especially unique and fragile ecosystem that is currently threatened by the proliferation of invasive species. As bison continue to persist in high numbers, restoration attempts will be undone. Soil quality will continue to decline, and invasive species will further dominate native landscapes. Many decades or centuries from now, the bison may become naturalized, becoming integrated into the island’s intricate ecosystem. However, if Catalina’s native ecosystem continues to deteriorate by the bison’s doing, residents may have to accept that this island is not a permanent home, but a makeshift residence that is breaking down, long expired, and in need of significant repair.
About the author: Lauren Stoneburner is a sophomore undergraduate majoring in Environmental Studies and Biological Anthropology at the USC Dana and David Dornsife College of Letters, Arts and Sciences.
Works Cited:
“History.” Catalina Island Conservancy. Catalina Island Conservancy, 2009. Web. 09 Aug. 2012. http://www.catalinaconservancy.org/index.php?s=wildlife .
Sweitzer, Rick; Van Vuren, Dirk. “Bison Study Executive Summary.” Santa Catalina Island Conservancy. Catalina Island Conservancy, 2009. Web. 07 Aug. 2012. http://www.catalinaconservancy.org/userfiles/files/Bison%2520Study%2520Executive%2520Summary.pdf .
Trivedi, Bijal P. “”Tourist” Bison Devastate California Island.” National Geographic. National Geographic Society, 17 Dec. 2001. Web. 07 Aug. 2012. http://news.nationalgeographic.com/news/2001/12/1217_TVbison.html .