Sea Turtles Benefiting >From Protected Areas plus 6 more
|
|
- Sea Turtles Benefiting From Protected Areas
- USGS Finds No Influence of Oil Platforms on Contaminant Levels in California Fishes
- Tiny Grazers Play Key Role in Marine Ecosystem Health
- Crowd-Sourcing the Nation: Using Volunteers for Enhanced Data Collection
- 25 Years Monitoring Alaska Volcanoes
- Proximity to Coal-Tar-Sealed Pavement Raises Risk of Cancer, Study Finds
- First Images Released From Newest Earth Observation Satellite
|
Sea Turtles Benefiting From Protected Areas Posted: 29 Apr 2013 08:00 AM PDT Study Offers First Look at Green Sea Turtle Habitat Use in the Dry TortugasAdditional Contact: Kristen Hart, Mobile Phone: 954-650-0336
DRY TORTUGAS, Fla. – Nesting green sea turtles are benefiting from marine protected areas by using habitats found within their boundaries, according to a U.S. Geological Survey study that is the first to track the federally protected turtles in Dry Tortugas National Park. Green turtles are listed as endangered in Florida and threatened throughout the rest of their range, and the habits of green sea turtles after their forays to nest on beaches in the Southeast U.S. have long remained a mystery. Until now, it was not clear whether the turtles made use of existing protected areas, and few details were available as to whether they were suited for supporting the green sea turtle’s survival. U.S. Geological Survey researchers confirmed the turtles' use of the protected areas by tracking nesting turtles with satellite tags and analyzing their movement patterns after they left beaches. "Our goal was to better understand what types of habitats they used at sea and whether they were in fact putting these designated areas to use. This study not only shows managers that these designated protected areas are already being used by turtles, but provides insight into the types of habitats they use most," said the study’s lead author, Kristen Hart, who works as a research ecologist for the U.S. Geological Survey. Hart's team made the discovery by fitting green sea turtle mothers with satellite tags after they came onto beaches within Dry Tortugas National Park to nest. After tracking their movements and analyzing their time at sea, the team located the areas turtles used between their nesting events and determined where turtles traveled after the nesting season was over. They found green sea turtles spending much of their time in protected sites within both Dry Tortugas National Park and the surrounding areas of the Florida Keys Marine National Sanctuary. "We were thrilled to find that these turtles used some areas already under 'protected' status. The ultimate goal is to help managers understand where these endangered turtles are spending their time both during the breeding period and then when they are at feeding areas. Given that worldwide declines in seagrasses – one of the most important habitats they rely on for food – has already been documented, this type of data is critical for managers," said Hart. The team learned about the turtle's habitat needs during the nesting season by using ATRIS, a georeferenced, underwater camera system developed by the USGS to collect over 195,000 seafloor images. Researchers surveyed the areas frequented by turtles within Dry Tortugas National Park by photographing the seafloor in a series of parallel lines totaling 70 kilometers (over 43 miles). Using a habitat map derived from those images, they found that the turtles most commonly used shallow seagrass beds and degraded coral reefs that have been overgrown by a mixed assemblage of other organisms, such as sea fans, sponges, and fire coral. "Our synergistic approach of combining satellite telemetry data with an extensive habitat map proved to be an effective way to find out exactly what habitats these nesting turtles were using in the Park," said Dave Zawada, a USGS research oceanographer and co-author on the study. The Dry Tortugas' population made shorter migrations than that typically seen among other green turtle populations around the world; this was only the second published study showing green turtles taking up residence at feeding grounds located quite near their breeding grounds. "We hope to keep pushing the frontier of what is known about in-water sea turtle habitat use, as this type of scientific information is vital for understanding whether conservation measures are effective," said Hart. The study, "Habitat use of breeding green turtles Chelonia mydas tagged in Dry Tortugas National Park: Making use of local and regional MPAs," was published this week in the journal Biological Conservation. About Green Sea Turtles Although their young feed on jellyfish and other invertebrates, adult green sea turtles feed on seagrasses and algae, making them the only herbivorous (vegetarian) species of sea turtle. In fact, their name comes from their greenish colored fat, which is thought to be caused by their diet. Green sea turtles are found around the world in three main types of habitat: nesting beaches, open ocean, and shallow water such as lagoons and shoals where they feed on marine grasses and algae found on the seafloor (‘benthic’ habitat). Within the U.S., green sea turtles are found from North Carolina to Florida, Hawaii, and the Virgin Islands and Puerto Rico. Their breeding populations in Florida are listed as endangered, but all other populations are listed as threatened. The nesting season for green turtles lasts throughout the summer, but is most concentrated in June and July. During nesting season, females nest at roughly two-week intervals, producing an average of five nests or "clutches." Each clutch contains an average of 135 eggs, which will hatch after incubating for about 2 months. |
||||
|
USGS Finds No Influence of Oil Platforms on Contaminant Levels in California Fishes Posted: 02 Apr 2013 02:09 PM PDT Fishes residing near oil platforms in southern California have similar contaminant levels as fishes in nearby natural sites, according to two recent reports by the U.S. Geological Survey, which were conducted to assist the Bureau of Ocean Energy Management (BOEM) in understanding potential consequences of offshore energy development. Since the underwater portion of many offshore oil and gas platforms often provides habitat to a large number of fishes and invertebrates, some stakeholders have called for ocean managers to consider a "rigs-to-reefs" option during the decommissioning phase of a platform. This option would maintain some of the submerged structure to function as an artificial reef after oil and gas production has ended. The findings of this study address questions regarding how the industrial legacy of this kind of artificial reef may affect local fish populations. Scientists analyzed the amount of contaminants from crude oil exposure present in three species of fish residing at oil platforms within the Santa Barbara Channel and the San Pedro Basin in California. The amount of contaminants present in fish tissue samples at seven platform sites was compared to samples at natural nearby sites. The brand new and recent USGS reports are available online. "As part of this study, we developed methods capable of detecting the extremely low levels of contaminants that we anticipated in these ocean fishes, especially since they avoid natural oil seeps," said USGS scientist Robert Gale. "These results will assist decision-makers in helping to protect the environment off the coast of California." Some of the most important contaminants related to oil operations are polycyclic aromatic hydrocarbons (PAHs). Several PAHs are probable human carcinogens and many are toxic to fish and other aquatic life. Scientists were able to develop a new, more accurate method of sampling small traces of PAHs that may have been ingested and broken down within the fish. Samples were taken from species thought to be most sensitive to PAH contamination. These species, including Pacific sanddab, kelp rockfish, and kelp bass, also tend to be targeted by fishermen. PAH concentrations were either very low or undetectable in all fish sampled for this study. "These important results suggest two things," said BOEM marine biologist Donna Schroeder. "First, existing offshore oil platforms provide food and shelter to local fishes without increasing their background contaminant loads. Second, since there is no detectable PAH signal from ongoing operations, we would expect that if the State of California wanted to implement a rigs-to-reefs program, there would likely be no change, pollution-wise, in the quality of the offshore environment, which appears to be pretty good." Scientists also looked at industrial chemicals in the Pacific sanddab species, including polychlorinated biphenyls (PCBs), flame retardants (polybrominated diphenylethers, PBDEs), and pesticides (OCPs). These contaminants were also found at low levels in all fish sampled, with no observed pattern between natural and platform habitats. The Bureau of Ocean Energy Management promotes energy independence, environmental protection and economic development through responsible, science-based management of offshore conventional and renewable energy. While the agency is responsible for analyzing the potential environmental impacts of removing oil and gas platforms in federal waters, the Bureau of Safety and Environmental Enforcement approves applications for decommissioning and ensures that they are conducted safely and in compliance with federal regulations. For additional information on BOEM activities, visit http://www.boem.gov/.
|
||||
|
Tiny Grazers Play Key Role in Marine Ecosystem Health Posted: 02 Apr 2013 06:00 AM PDT
LAFAYETTE - Tiny sea creatures no bigger than a thumbtack are being credited for playing a key role in helping provide healthy habitats for many kinds of seafood, according to a new study by the Virginia Institute of Marine Science and U.S. Geological Survey. The little crustacean “grazers,” some resembling tiny shrimp, are critical in protecting seagrasses from overgrowth by algae, helping keep these aquatic havens healthy for native and economically important species. Crustaceans are tiny to very large shelled animals that include crab, shrimp, and lobster. The researchers found that these plant-eating animals feast on the nuisance algae that grow on seagrass, ultimately helping maintain the seagrass that provides nurseries for seafood. The grazers also serve as food themselves for animals higher on the food chain. Drifting seaweed, usually thought of as a nuisance, also plays a part in this process, providing an important habitat for the grazing animals that keep the seagrass clean. “Inconspicuous creatures often play big roles in supporting productive ecosystems,” said Matt Whalen, the study’s lead author who conducted this work while at VIMS and is now at the University of California, Davis. “Think of how vital honeybees are for pollinating tree crops or what our soils would look like if we did not have earthworms. In seagrass systems, tiny grazers promote healthy seagrasses by ensuring algae is quickly consumed rather than overgrowing the seagrass. And by providing additional refuge from predators, fleshy seaweeds that drift in and out of seagrass beds can maintain larger grazer populations and enhance their positive impact on seagrass.” USGS scientist Jim Grace, a study coauthor, emphasized that seagrass habitats are also quite beneficial to people. “Not only do these areas serve as nurseries for commercially important fish and shellfish, such as blue crabs, red drum, and some Pacific rockfish, but they also help clean our water and buffer our coastal communities by providing shoreline protection from storms,” Grace said. “These tiny animals, by going about their daily business of grazing, are integral to keeping healthy seagrass beds healthy.”
In fact, the authors wrote, if not for the algal munching of these grazers, algae could blanket the seagrasses, blocking out sunlight and preventing them from photosynthesizing, which would ultimately kill the seagrasses. Seagrass declines in some areas are attributed partly to excessive nutrients in water bodies stimulating excessive algal growth on seagrasses. “Coastal managers have been concerned for years about excess fertilizer and sediment loads that hurt seagrasses,” said J. Emmett Duffy of Virginia Institute of Marine Science and coauthor of the study. “Our results provide convincing field evidence that grazing by small animals can be just as important as good water quality in preventing nuisance algae blooms and keeping seagrass beds healthy.” The USGS scientists involved in this study serve as members of a worldwide consortium of researchers examining the health of seagrasses. This research by Virginia Institute of Marine Science and USGS researchers is the first in a series of studies worldwide on seagrass ecosystems. The study, “Temporal shifts in top-down versus bottom-up control of epiphytic algae in a seagrass ecosystem,” was published in the recent issue of Ecology, a journal by the Ecological Society of America. |
||||
|
Crowd-Sourcing the Nation: Using Volunteers for Enhanced Data Collection Posted: 01 Apr 2013 03:41 PM PDT The USGS is expanding the involvement of volunteers to enhance data collection about structures for The National Map. This program, known as The National Map Corps, focuses on encouraging citizens to collect data relating to structures by both adding new features and/or correcting existing data within The National Map database. These structures can include schools, hospitals, post offices, police stations and other important public places. Collaborative pilot projects in Colorado were recently used to test the concept of crowd-sourcing. While the project is on-going, early indications point to positive results and show the success of using TNMC volunteers to enhance data sets. Over a trial period of ten months, 143 volunteers collected, improved, or deleted data on more than 6,400 structures in Colorado. The volunteers’ actions were accurate and exceeded USGS quality standards. In the Colorado pilot project the volunteer-collected data showed an improvement of approximately 25 percent in both location and attribute accuracy for existing data points. Completeness, or the extent to which all appropriate features were identified and recorded, was nearly perfect. The significant results of the Colorado pilot have led to a phased, nation-wide expansion of the crowd-sourcing /volunteer project. The states in the first expansion of TNMC are: Arkansas, Alaska, Colorado, Delaware, Georgia, Idaho, Maryland, Michigan, Montana, North Dakota, New Jersey, New Mexico, Ohio, Oregon, South Carolina, Utah, Washington, West Virginia After an evaluation of the quality and procedures of the first group of states, the second set will be made available. Ultimately, by the end of 2013, the third batch of states will complete the expansion of the program. "The response by volunteers in Colorado exceeded our expectations both in terms of the number of volunteers and the quality of the data they collected”, said Kari Craun, the Director of the USGS National Geospatial Technical Operations Center. “The Volunteered Geographic Information (VGI) community represents a fantastic, untapped resource to assist USGS in maintaining data that are part of The National Map.” While some familiarity with the area that a volunteer chooses is helpful, one doesn’t have to live near a particular place to contribute. The tools on TNMC website, along with ancillary information available on the Internet, are generally sufficient to edit a distant area. There have been several instances of crowd-sourced geographic information making significant contributions to research and databases in government, private sector, and non-profit organizations. The goal of the TNMC is to provide data for the nation’s primary federal mapping agency in its effort to provide accurate and authoritative spatial data via the web-based National Map. The citizen geographers/cartographers who participate in this program will make a significant addition to the USGS’s ability to provide accurate information to the public. Data collected by volunteers become part of TNM Structures dataset which is available to users free of charge. Without a network of volunteers, the desired information would not be collected this year and the existing data would not be updated. TNMC volunteers perform important work that otherwise will not be accomplished in the foreseeable future. Becoming a volunteer for TNMC is easy; go to the National Map Corps website to learn more and to sign up as a volunteer. If you have access to the Internet and are willing to dedicate some time to editing map data, we hope you will consider participating! |
||||
|
25 Years Monitoring Alaska Volcanoes Posted: 01 Apr 2013 10:00 AM PDT Twenty-five years of monitoring and studying Alaska's volcanoes by the Alaska Volcano Observatory have improved global understanding of how volcanoes work and how to live safely with volcanic eruptions. Timely warnings from AVO throughout its 25-year history have helped reduce the impact of erupting volcanoes, protecting lives, property, and economic well-being. On April 1, the Alaska Volcano Observatory, a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys, will mark its 25th anniversary. "Since 1988, AVO has responded to over 70 eruptive events from Alaska’s 52 historically active volcanoes," said John Power, USGS geophysicist and scientist-in-charge of AVO. "Many of these eruptions affected local and international air traffic, oil production, the fishing industry, municipalities, businesses, and citizens." The primary volcano hazard in Alaska is airborne ash that endangers aircraft flying the busy North Pacific air routes connecting North America and Asia. The hazard played out dramatically on December 15, 1989 when a wide-body passenger jet encountered an ash cloud from Redoubt Volcano and lost power in all four engines over the Talkeetna Mountains. Fortunately, after more than 4 harrowing minutes of descent, engines were restarted and the plane landed safely in Anchorage. This near-tragedy prompted renewed international efforts to more effectively address the hazards of airborne volcanic ash. In addition to endangering aircraft, volcanoes near population centers can pose significant hazards to infrastructure and communities from ash fall, lahars, and other rapidly flowing mixtures of hot rock fragments, fluids, and gases. AVO has developed a far-reaching volcano monitoring program in Alaska and partnered with federal, state and municipal agencies, to improve warnings of volcanic eruptions. AVO led the development of the standard Aviation Color Code to communicate hazards in a simple, consistent manner; this warning system is now endorsed by the International Civil Aviation Organization for use by volcano observatories worldwide. AVO pioneered cooperative programs with volcanologists in the Russian Far East, also home to dozens of explosive volcanoes that threaten aircraft, to create a system to warn the aviation industry of eruptions in Kamchatka and the Kuriles. Over 25 years, AVO expanded from an early focus on just Cook Inlet volcanoes to a current monitoring and research program that includes daily observations of all 52 historically active volcanoes in Alaska. To address the aviation hazard, AVO expanded ground-based monitoring networks from Cook Inlet to volcanoes on the Alaska Peninsula and Aleutian Islands. Throughout the years, AVO and its colleagues developed innovative ways to track earthquake activity, ground deformation, and volcanic gas output, and analyze satellite imagery in the harsh Alaskan environment. Geologic studies of volcanoes and eruptions by AVO scientists provide insights into eruptive histories, information needed to assess future hazards and inform planning efforts. AVO issues daily and weekly updates of volcanic activity in Alaska. The most recent information along with a wide range of volcano information, real-time data, and images is available on the AVO website. Volcanic activity notices are also served through Twitter @alaska_avo. The University of Alaska Fairbanks Geophysical Institute turns observations into information, from the center of the Earth, to the center of the Sun. Visit the UAFGI website for more information. The Alaska Division of Geological and Geophysical Surveys determines the potential of Alaskan land for resources, groundwater, and geologic hazards. More information is available online. |
||||
|
Proximity to Coal-Tar-Sealed Pavement Raises Risk of Cancer, Study Finds Posted: 28 Mar 2013 07:10 AM PDT People living near asphalt pavement sealed with coal tar have an elevated risk of cancer, according to a study in the journal Environmental Science and Technology. Much of this calculated excess risk results from exposures in children, age six or younger, to polycyclic aromatic hydrocarbons (PAHs) from the sealant. "The increased cancer risk associated with coal-tar-sealed asphalt (CSA) likely affects a large number of people in the U.S. Our results indicate that the presence of coal-tar-based pavement sealants is associated with significant increases in estimated excess lifetime cancer risk for nearby residents," said E. Spencer Williams, Ph.D., principal author of the study and Baylor University assistant research scientist at the Center for Reservoir and Aquatic Systems Research in Baylor's College of Arts & Sciences. Researchers from Baylor University in Waco, Texas, and the U.S. Geological Survey in Austin, Texas, are the first to report on the potential human health effects of PAHs in settled house dust and soil in living spaces and soil adjacent to parking lots sealed with coal-tar-based products. "Exposure to these compounds in settled house dust is a particularly important source of risk for children younger than six years of age, as they are expected to ingest this material at higher rates," Williams said. "This indicates that the use of coal-tar-based pavement sealants magnifies aggregate exposures to PAHs in children and adults in residences adjacent to where these products are used and is associated with human health risks in excess of widely accepted standards." Data on PAHs in settled house dust used for this analysis were published previously by the same authors. In that study, settled house dust and parking lot dust were sampled for 23 ground-floor apartments in Austin, Texas. The parking lot surfaces adjacent to the apartments were coal-tar-sealed asphalt, asphalt-based sealant over asphalt pavement, or unsealed concrete. Concentrations of PAHs were 25 times higher in house dust in residences adjacent to coal-tar-sealed pavement compared to those with other pavement types. "This study was the first to find a strong association between a product or a behavior and PAHs in house dust," said Barbara Mahler, the USGS research hydrologist who oversaw the study. For this study, doses and risk associated with residences adjacent to unsealed asphalt lots were considered relative to those adjacent to (CSA) parking lots. Benzo(a)pyrene concentrations in CSA-affected settled house dust were high relative to those reported in most parts of the U.S. where coal-tar-based sealcoat is not used (California and Arizona). Data for PAHs in coal-tar-sealed asphalt-affected soils and unsealed asphalt-affected soils are available from samples from New Hampshire and suburban Chicago. The analysis did not consider exposure to the dust on the pavement itself, which has PAH concentrations 10s to 100s of times higher than those in house dust or soil, or inhalation of air over sealed pavement. "Over time, about half of the PAHs in the sealcoat are released into the air, and concentrations in air are extremely high, particularly in the hours to days after application," said Peter Van Metre, USGS research hydrologist and author of two papers on volatilization of PAHs from sealcoat. Sealcoat is a black, shiny substance sprayed or painted on the asphalt pavement of parking lots, driveways, and playgrounds to improve appearance and protect the underlying asphalt. An estimated 85 million gallons of coal-tar-based sealant are applied to pavement each year, primarily east of the Continental Divide in the U.S. and parts of Canada. Coal-tar-based pavement sealants are 15 to 35 percent coal-tar pitch, which has been classified as a human carcinogen by the International Agency for Research on Cancer. Over time, the dried sealant is worn away from pavement surfaces, and the resulting mobile dust particles can be transported into nearby homes. "Although the analysis presented here is based on a limited dataset, the results indicate that biomonitoring might be warranted to characterize the exposure of children and adults to PAHs associated with coal-tar-based pavement sealant," Williams said. "Further investigation is also needed into the impacts of coal-tar-based pavement sealants on PAH concentrations in indoor and outdoor environments." To learn more about Baylor University and their nationally ranked research program, visit their website. |
||||
|
First Images Released From Newest Earth Observation Satellite Posted: 21 Mar 2013 09:01 AM PDT WASHINGTON -- NASA and the Department of the Interior's U.S. Geological Survey (USGS) have released the first images from the Landsat Data Continuity Mission (LDCM) satellite, which was launched Feb. 11. The natural-color images show the intersection of the United States Great Plains and the Front Range of the Rocky Mountains in Wyoming and Colorado. In the images, green coniferous forests in the mountains stretch down to the brown plains with Denver and other cities strung south to north. LDCM acquired the images at about 1:40 p.m. EDT March 18. The satellite's Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) instruments observed the scene simultaneously. The USGS Earth Resources Observation and Science Center in Sioux Falls, S.D., processed the data. "We are very excited about this first collection of simultaneous imagery," said Jim Irons, LDCM project scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. "These images confirm we have two healthy, functioning sensors that survived the rigors of launch and insertion into Earth orbit." Since launch, LDCM has been going through on-orbit testing. The mission operations team has completed its review of all major spacecraft and instrument subsystems, and performed multiple spacecraft attitude maneuvers to verify the ability to accurately point the instruments. The two LDCM sensors collect data simultaneously over the same ground path. OLI collects light reflected off the surface of Earth in nine different regions of the electromagnetic spectrum, including bands of visible light and near-infrared and short-wave-infrared bands, which are beyond human vision. TIRS collects data at two longer wavelength thermal infrared bands that measure heat emitted from the surface. By looking at different band combinations, scientists can distinguish features on the land surface. These features include forests and how they respond to natural and human-caused disturbances, and the health of agricultural crops and how much water they use. Data from LDCM will extend a continuous, 40-year-long data record of Earth's surface from previous Landsat satellites, an unmatched, impartial perspective that allows scientists to study how landscapes all across the world change through time. "These first scenes from the new Landsat satellite continue the remarkable output from the Landsat program with better, more useful imagery and information," said Matthew C. Larsen, associate director for climate and land use change at the U.S. Geological Survey in Reston, Va. "We are gratified that this productive partnership between USGS and NASA has maintained the continuity and utility of this essential satellite tool, providing the foundation for land and water management around the globe." As planned, LDCM currently is flying in an orbit slightly lower than its operational orbit of 438 miles (705 kilometers) above Earth's surface. As the spacecraft's thrusters raise its orbit, the NASA-USGS team will take the opportunity to collect imagery while LDCM is flying under Landsat 7, also operating in orbit. Measurements collected simultaneously from both satellites will allow the team to cross-calibrate the LDCM sensors with Landsat 7's Enhanced Thematic Mapper-Plus instrument. "So far, our checkout activities have gone extremely well," said Ken Schwer, LDCM project manager at Goddard. "The mission operations team has done a tremendous job getting us to the point of imaging Earth." During the next few weeks, this team will calibrate the instruments and verify they meet performance specifications. After its checkout and commissioning phase is complete, LDCM will begin its normal operations in May. At that time, NASA will hand over control of the satellite to the USGS, which will operate it throughout its planned five-year mission life. The satellite will be renamed Landsat 8. USGS will process data from OLI and TIRS and add it to the Landsat Data Archive at the USGS Earth Resources Observation and Science Center, where it will be distributed for free via the Internet. Visit LDCM First Images to view the images. For further information about LDCM, visit LDCM Mission. For status and technical information about all Landsat satellites, visit Landsat Missions. |
- Prev by Date: Rising Seas Could Threaten Many Acadia NP Marshes
- Next by Date: USGS Releases New Oil and Gas Assessment for Bakken and Three Forks Formations
- Previous by thread: Rising Seas Could Threaten Many Acadia NP Marshes
- Next by thread: USGS Releases New Oil and Gas Assessment for Bakken and Three Forks Formations
- Index(es):
 |