June 5, 1998 Contact: Tim Stephens (408) 459-2495; stephens@cats.ucsc.edu
OCEAN SCIENCE RESEARCH AT UC SANTA CRUZ
The Institute of Marine Sciences (IMS) at the University of California, Santa Cruz, brings together researchers working in many different fields. The IMS includes the Joseph M. Long Marine Laboratory, an internationally renowned center for research in marine mammal physiology and ecology, marine invertebrate ecology, and marine toxicology. IMS researchers also work in the Earth and Marine Sciences Building on the UCSC campus studying marine geology and geophysics, ocean processes, paleoceanography, and coastal processes and hazards.
The following compilation of research summaries provides an overview of a range of ongoing ocean research projects at UCSC. Contact information is provided for some of the researchers involved in these projects.
Understanding long-term effects of El Ni=F1o Daniel Costa, professor of biology: 459-2786; costa@biology.ucsc.edu Donald Croll, research biologist: 459-3610; dcroll@cats.ucsc.edu Gary Griggs, professor of earth science and director of IMS: 459-5006; griggs@cats.ucsc.edu
UCSC scientists are involved in several El Ni=F1o-related projects, studying how changes in ocean currents affect the marine food web, how altered weather patterns affect elephant seal behavior, and how powerful winter storms accelerate coastal erosion and damage manmade structures.
The most visible impacts from El Ni=F1o are along the coastline, where the winter's driving rains and pounding waves have washed away beaches, bluffs, and more than a few houses. Gary Griggs, a marine geologist and director of the IMS, has been studying erosion along the California shoreline and says 86% of it is actively eroding. He has received funding from the Federal Emergency Management Agency (FEMA) to precisely measure the rate of erosion along the coast of Santa Cruz County. Erosion shaves off, on average, about six inches to a foot from the California coastline each year. In an El Ni=F1o year, however, losses of fou= r to ten feet or more are not unusual, Griggs says.
Marine animals from the smallest to the largest have also been affected by El Ni=F1o, as Don Croll and Baldo Marinovic are finding in their studies of whales and krill, tiny zooplankton on which certain whales feed, including the humpback whale and the massive blue whale. The changes in wind and ocean-current patterns that accompany El Ni=F1o have seriously diminished the normal upwelling of nutrients from deeper water and changed the distributions of the different species of krill along the coastline. As a result, Croll says, there may not be enough food for the krill born in =46ebruary and March to all reach adulthood this summer. And if there aren't enough adult krill, there won't be as much food for the whales that usually come into Monterey Bay to feed from July to September.
Storms spawned by El Ni=F1o have already seriously affected the elephant seal population about 20 miles north of Santa Cruz at A=F1o Nuevo State Reserve, according to work by Dan Costa's research group. The mortality rate of pups born over the winter was 21%, three times the usual rate, says Costa. The increased mortality was mainly due to the fierce waves that attacked the coast, tearing young pups from their mothers' sides. Other age groups also appear to have suffered, as Costa's group has begun noting much lower rates of return among yearlings who were marked for identification last year before they departed to spend the winter out at sea.
Costa's colleague Dan Crocker, an assistant research biologist, is studying the foraging habits of elephant seals, who spend most of their time far out at sea and dive to depths of a mile or more in search of food. Data from tracking devices on ten adult females indicate that many of them had to search longer for smaller patches of prey this year, suggesting that the usual distribution of prey has been radically disrupted by El Ni=F1o, Crocker says.
California sea lions also may have been affected by a redistribution of prey, as adult females are showing up farther north than usual, and preliminary data from their current birthing season indicates a mortality rate at birth far above the norm.
Biodiversity of Monterey Bay Donald Potts, professor of biology: 459-4417; potts@biology.ucsc.edu
Donald Potts is an expert on the biodiversity and ecology of coral reefs, with long-term projects focusing on the ecology and evolution of reef-building corals and how they respond to environmental change. He is also convenor of a group of scientists developing research projects to study marine biodiversity in the Monterey Bay National Marine Sanctuary.
Potts coordinated preparation of a proposal for a National Marine Biodiversity Research Initiative that is being presented to President Clinton in conjunction with the National Ocean Conference. The proposal envisions a pilot project focused on Monterey Bay, with provision for a complementary program on the East Coast.
"With the extraordinary diversity of Monterey Bay, the richest known temperate coastal region in the world, this is an ideal place to concentrate our initial efforts," Potts says.
Although the coastline of Monterey Bay has been intensively studied for decades, scientists are still recognizing new species of large, common intertidal and shallow-water organisms here. This suggests that our knowledge of the inhabitants of deeper and less accessible offshore waters must be seriously deficient, Potts says. As a result, scientists cannot predict with certainty the effects of human activities on the marine environment.
"Environmental impacts are creating the biological analog of stirring a huge vat of unknown chemicals," Potts says. "Populations of species are the key functional units in all ecological systems. Effective sustainable management of biodiversity will not be possible unless we know what species are present, what their key characteristics are, and how they interact."
One goal of the marine biodiversity initiative is to establish systems for identifying species, recording their characteristics and basic ecological information, and storing that information in databases readily accessible to scientists, managers, industry, and the public. The initiative also aims to develop programs for training future generations of scientists and researchers who will work with biodiversity, and to develop models for future national and international programs.
Marine ecology and conservation Mark Carr, assistant professor of biology: 459-3958; carr@biology.ucsc.edu James Estes, adjunct professor of biology: 459-2820; jestes@cats.ucsc.edu Marc Mangel, professor of conservation biology: 459-4942; msmangel@cats.ucsc.edu
Researchers at UCSC are studying many different aspects of ecological communities in marine and coastal environments. Their combined efforts are providing a picture of how the plants and animals in these communities interact with each other, what they need to survive, and how they respond to changes in their environment. Some of these researchers also seek to apply their knowledge of basic ecology to practical problems, such as how to manage fisheries and how to protect sensitive marine environments from human impacts.
Mark Carr's research focuses on the types of fish that inhabit nearshore rocky reefs. Jim Estes has spent years studying the role of sea otters in the ecology of kelp beds. Marc Mangel is an expert on fisheries management whose research focuses on salmon populations.
Mangel, Estes, Carr, and others at UCSC hope to establish a long-term environmental monitoring project throughout the Monterey Bay National Marine Sanctuary. Such a project would be a collaborative interdisciplinary effort involving several research institutions.
The problem of managing marine resources is complex, in part because of the large spatial scale of many processes in the sea, Estes says. A variety of management approaches operating in concert may be needed to ensure the sustainability of ocean resources.
"Marine reserves are one important tool, and we are also trying to develop new methods to enhance or sustain marine fisheries," Carr says.
Algal blooms and toxic phytoplankton Mary Silver, professor of ocean sciences: 459-2908; msilver@cats.ucsc.edu
Microscopic phytoplankton are the grazing pastures of the sea, the base of the food chain for most marine life. Some of these tiny algae produce toxins that can build up in the food chain, accumulating in fish and eventually causing fish-eating birds and other marine animals to die in large numbers.
Mary Silver has been studying this phenomenon since 1991, when bird deaths in Monterey Bay were traced to a proliferation or "bloom" of toxic algae. Currently, Silver and others suspect a similar bloom is responsible for recent deaths of sea lions along the California coast.
Certain temperature and nutrient conditions seem to favor the growth of toxic phytoplankton. The role of humans in creating these conditions remains controversial, Silver says.
Silver works with many other researchers to investigate this problem. Her collaborators include David Jessup at the California Department of Fish and Game's Marine Wildlife Veterinary Care and Research Center and researchers at the Monterey Bay Aquarium Research Institute.
Although algal toxins occasionally cause illness or death in humans, state monitoring programs exist to ensure seafood safety. Silver works closely with state regulators to keep them informed when blooms of toxic algae occur in Monterey Bay.
Preparing effective responses to oil spills Ronald Tjeerdema, professor of chemistry and biochemistry: 459-2917; tjeerdem@hydrogen.ucsc.edu
UCSC researchers are studying the effects of oil spills on sea creatures and the effectiveness of oil-spill cleanup techniques. A state-of-the-art Oiled Seabird Facility is being added to the state Department of Fish and Game's Marine Wildlife Veterinary Care and Research Center located at Long Marine Lab.
A research group headed by Ron Tjeerdema is looking at several different aspects of oil spills. In one study, the group is examining two dispersants (compounds that break up oil) to see which works best on any of about a dozen different types of oil that might be spilled at sea. Dispersants are essentially detergents that break up oil into tiny droplets, which sink to the bottom of the ocean. The group is testing them under different temperature and salinity conditions. The goal is to produce a guide to help agencies involved in clean-up operations choose the best dispersant for any conditions.
A second study is comparing the toxicity to marine life of various oils, dispersants, and combinations of the two. The test subjects are giant kelp, abalone, and topsmelt in their early stages of life. Detergent and oil in high enough concentrations can directly kill marine life. In addition, both abalone and topsmelt can develop narcosis from exposure to some detergents or oils, which renders them more vulnerable to predators. Again, the goal is to guide clean-up efforts.
"If there's an oil spill, agencies can look up the type of oil and the dispersant and get a rough comparative idea of how toxic the combination will be if they use that dispersant," says Tjeerdema.
A third study looks at the absorption of oil by marine organisms after dispersion by a detergent. Tjeerdema's group studied three different types of organisms: algae, invertebrates, and fish. They found that while fish and invertebrates didn't seem to be directly affected, the amount of oil ending up in algae increased when detergent was present.
Regardless of whether dispersants are used on an oil spill, there will be at least some marine mammals that get coated with oil before anything can be done. When that happens, there are facilities waiting to help. Next door to UCSC's Long Marine Lab is the DFG's Marine Wildlife Veterinary Care and Research Center, opened last July, which has space to care for up to 125 oiled sea otters as well as other marine mammals and birds. An Oiled Seabird Facility is also being built at Long Marine Lab and will be able to treat up to 150 birds the size of pelicans and greater numbers of smaller seabirds.
The perceptual world of pinnipeds Ronald Schusterman, adjunct professor of biology and ocean sciences: 459-334= 5
A remarkable quartet of trained marine mammals is helping scientists understand how pinnipeds see, hear, and think about the world around them. Meet the sea lions Rocky and Rio, Sprouts the harbor seal, and Burnyce, the world's only trained elephant seal.
Years of research by Ron Schusterman and others have yielded a fascinating picture of the sensory and cognitive experiences of seals and sea lions, the flippered amphibious carnivores known collectively as pinnipeds. Their awareness of the world, it seems, has evolved to meet both the general needs of marine mammals and the special challenges each species faces in day-to-day life. The research also suggests that human impacts, such as noise from boat traffic, might interfere with pinnipeds' normal activities.
All four of UCSC's captive pinnipeds were either born in captivity or rescued as stranded orphans. Their research activities include wearing special headphones, detecting dim flashes of light, and recognizing pairs of pictures.
Pinnipeds communicate through a wide variety of growls, bellows, snorts, and whines. Whether a species hears better on land or underwater seems to depend on where they do most of their socializing. The California sea lions hear better on land, while Burnyce the elephant seal hears far better underwater. Burnyce also shows surprising ability to hear high frequencies, perhaps because elephant seals need to keep a sharp ear out for killer whales, which locate prey by making high-pitched clicks and listening for the echoes.
Schusterman's team also tested the animals' visual abilities to determine how well they can see in low-light conditions. Burnyce detected far dimmer flashes of light than any of her companions-not surprising since elephant seals routinely dive thousands of feet into the blue-black depths. Rio did slightly better than Sprouts, which makes sense because California sea lions spend more time foraging at night than do harbor seals.
Perhaps the most amazing talent the pinnipeds have shown involves matching pairs of pictures. Rocky and Rio can both point out pairs of pictures with their noses when shown a selection of images at poolside. Schusterman's group is convinced this ability indicates the sea lions have the kind of cognitive skills that linguists would consider forerunners of language. The researchers think these skills might be used by wild sea lions to classify other animals, separate family from strangers or predators, and navigate in three dimensions.
Ocean Drilling Program reveals seafloor secrets Margaret Delaney, professor of ocean sciences: 459-4736; delaney@cats.ucsc.e= du J. Casey Moore, professor of earth sciences: 459-2574; cmoore@earthsci.ucsc.= edu Eli Silver, professor of earth sciences: 459-2266; silver@earthsci.ucsc.edu
The Ocean Drilling Program (ODP) is an internationally financed operation overseen by Texas A&M University, with participating scientists from around the world. Dozens of UCSC scientists have played important roles in many of the ODP expeditions.
"The level of our involvement with ocean drilling is really astounding for a place this size," says Eli Silver, director of UCSC's Institute of Tectonics.
Silver's work with ODP has taken him on a number of expeditions, often to places where the tectonic plates of the earth's crust are colliding. There, he's probed the ocean sediments being carried down into the earth as one plate slides under another. These sediments often return to the surface in new forms during volcanic eruptions.
J. Casey Moore has cruised with ODP several times to plate boundaries, where his research group has found underground fluid channels, the subsurface version of a river. Moore says data from such channels could play an important role in anticipating the massive earthquakes produced where ocean floor is being forced under continental crust. Increased water pressure in the channels indicates greater pressures along the plate boundary, which in turn suggests a greater likelihood of earthquakes.
Margaret Delaney's ODP research involved measuring the chemical composition of the sediments to trace the chemical history of the oceans. She is especially interested in the nutrient history of the ocean, and her work has helped establish long-term records of phosphorus deposition in the seafloor. Her work also addresses how the composition of calcite microfossils may change after deposition in the sediments, which is important because these fossils are a primary tool in deciphering the past composition of the ocean. The results may force scientists to change the way they measure and interpret the ocean's chemical history.
Three other UCSC faculty are also closely involved in ODP research: Andrew Fisher, assistant professor of earth sciences (afisher@earthsci.ucsc.edu); Christina Ravelo, assistant professor of ocean sciences (acr@aphrodite.ucsc.edu); and James Zachos, associate professor of earth sciences (jzachos@earthsci.ucsc.edu).
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