Home » About » Research Overview » Marine Biodiversity and Conservation

Marine Biodiversity and Conservation

Coral Reefs and Marine Diversity

Scientists in the Center for Marine Biodiversity and Conservation at Scripps are transforming our understanding of the world's coral reefs and the diversity of life in the seas. Using the latest techniques of molecular biology, the researchers are discovering unsuspected genetic complexity within what was previously thought to be a single species of coral and other marine organisms. These studies have led to the realization that estimates of marine diversity are probably too low by a factor of ten. These insights may help explain previously enigmatic phenomena, including coral bleaching, a threat to reefs worldwide.

Food Shortage in the Deep

A seven-year study by Scripps researchers of food supply and demand in the deep eastern North Pacific revealed that marine organisms that live on the ocean bottom suffered from a long-term food shortage between 1989 and 1996. The ratio of food supply to food demand decreased by nearly 50 percent in that period. The researchers tracked the adequacy of the food supply of organisms that live on the ocean bottom at a depth of more than 13,000 feet below the ocean surface. A likely culprit for the decline in food supply is a documented increase in ocean surface temperatures. Organisms affected include an array of bottom dwellers from bacteria and protozoa to worms and various crustaceans. Scientists say that if the food deficit continues, the configuration of deep-sea communities of organisms will change and some species will become extinct.

Monitoring the Ocean Food Web

Scripps scientists use satellite remote sensing and modeling applications to study the distribution and dynamics of phytoplankton in the world's oceans. Phytoplankton are microscopic plants, which form the base of the ocean food web. They are responsible for approximately one-half of global photosynthesis and play a vital role in stabilizing atmospheric carbon dioxide. Understanding the role of phytoplankton in the marine carbon cycle is essential to predicting the ocean's response to climate change. Satellite ocean color sensors are used to acquire such data on a global basis.

Kelp Forests

Scripps scientists are world leaders in the study of kelp ecosystems and the management of kelp forest resources. Their research provides insights into the dynamics of this ecosystem and the impact of abalone, sea urchins, El Ni o events, and kelp fisheries. Kelp harvesting is a major industry, and kelp products are important for a range of consumer goods, including food additives, pharmaceuticals, cosmetics, and paper. Most important, the kelp community is an extremely productive ecosystem of great commercial, recreational, and aesthetic value. Multiuse management depends on sophisticated understanding of the environmental and ecological factors sustaining the ecosystem.

Antarctic Wildlife

Scripps researchers have been investigating the natural environment of Antarctica for several decades. Scientists study the dynamics of the Antarctic Circumpolar Current that helps drive major climate systems and ties the world's oceans together physically and biologically. Recent Antarctic research explored how zooplankton survive under the sea ice during the harsh winter when food is scarce. Scripps researchers endured extreme discomfort to dive under the ice shelf for their studies of marine organisms. In another study, Scripps researchers found that adult emperor penguins remain near Antarctic pack ice. Although those breeding in the Antarctic Ross Sea never seem to leave that area, summer or winter, penguins travel hundreds of miles from the colony to the eastern Ross Sea to molt. After a month of molting in heavy pack ice, they return to the colony, taking about three months on the return journey.

Raising Threatened Species

Human activities are growing threats to many marine organisms. Corals, sea horses, and colorful tropical fish are among the threatened species being raised at the Birch Aquarium at Scripps. Scripps aquarists are conducting a coral propagation project to help understand and conserve corals. The program recently expanded to include a new display of Caribbean corals. Using a specially designed facility, Scripps aquarists are raising nine species of sea horses and have sent more than 1,400 sea horses to 45 facilities around the world.

FISH TV

Scripps researchers have designed and tested an electronics system that uses sound to create visual images of ocean life. Combining recently developed sonar techniques with advanced computer processing, the system produces three-dimensional computer pictures of ocean animals, ranging from plankton to large fish. This new technology helps define the interconnections among plants, animals, and their physical environment. It has been used by a large-scale research program to understand marine ecosystem relationships.

Tracking Changes in the California Current

The California Cooperative Oceanic Fisheries Investigations (CalCOFI) recently celebrated 50 years of monitoring the ecology and fisheries of the California Current system. CalCOFI was created to discover why the large California sardine fishery collapsed. Its studies illustrate the importance of being able to distinguish between natural and anthropogenic changes in the sea and the necessity of studying individual populations in the context of their ecosystems. It is now thought that fishing accelerated but was not the sole cause of the sardine's decline. Apparently, changes in the ocean more than the absence of fishing spurred the sardine's recent recovery. CalCOFI studies showed that zooplankton, microscopic floating animals on which sardines feed, declined from the 1950s through early 1998, especially during El Ni o events. Populations rebounded in 1999-2000, but only time will tell if this is a short-term or long-term change.

Plunging Plankton Populations

Scientists at Scripps recently reported that an analysis of CalCOFI data over the last 45 years showed that zooplankton populations in southern California waters declined by more than half. The observed decline may have been linked to a warming of the ocean surface in the region over the same period. Zooplankton form a vital link near the base of the food web, and a decline in their numbers could pose a threat to other marine life. It is not known if recent declines observed in some species of sea birds (the sooty shearwater by 90 percent) and certain commercial fish species (anchovy, jack mackerel, rockfish) are related to the decline in plankton. The latest CalCOFI data indicate a reversal of this decline but further study is needed to confirm this trend.

Plankton Patches and the Ocean in Motion

Scripps scientists are using computer models and novel instruments to explore how physical motion affects the dynamics of ocean life. The tiny plants and animals (plankton) that inhabit the ocean are at the mercy of the currents. These water motions, from turbulence to ocean gyres, control the interactions between plankton and their environment and among the organisms themselves. These interactions range from the formation of tiny plankton patches that persist for seconds to the formation of giant red tides that can stretch for hundreds of miles and last for months.

Deep-Sea Exploration

Exploring the deep ocean is a long-standing tradition at Scripps. Several research groups study the marine life found at great depths and seafloor geology. Scripps deep-sea researchers use the submersible Alvin and the Jason/Medea remotely operated vehicles from Woods Hole Oceanographic Institution, the Scripps Deep Tow instrumentation system, the U.S. Navy's advanced tethered vehicle, and other specialized equipment to carry out their studies.