New Genetic Test Detects Manatees’ Recent Presence in Fresh or Saltwater
March 19—USGS scientists have developed the first laboratory test that can pick up traces of manatees’ genetic material in the waterways where they live. Using a water sample collected in the field, the innovative environmental DNA test can reveal whether one or more of the elusive marine mammals has been in the area within the past month. The test can detect the presence of manatees where other methods won’t work, help scientists identify the habitats manatees use and the patterns of their seasonal movements, and inform efforts to bring back wild manatee populations that are considered close to extinction, said USGS research geneticist Margaret Hunter. “Environmental DNA detection is the wave of the future for monitoring species that are difficult to find,” Hunter said. “We’re getting a more complete picture of these wild populations, without disturbing them.”
USGS Authors New Report on Seismic Hazard, Risk, and Design for South America
March 14—South America is one of the most earthquake-prone regions of the world and has witnessed tremendous losses throughout recorded history. A recently released USGS report provides probabilistic tools to help engineers assess seismic hazards, risk, and building code requirements, potentially saving lives and dollars. The seismic activity in this continent is driven by the South American Subduction Zone and other complex fault interactions. Future human and financial losses can be mitigated through making informed decisions based on where future earthquakes may occur, how often they might occur, and how strong the ground will shake. Such information is the purpose of probabilistic (i.e., based on a mathematical forecast) seismic hazard models that are applied in building codes, insurance models, and public policy.
Modern Perspective on Gas Hydrates
March 8—The number of discoveries and advances regarding gas hydrates has advanced at a rapid pace in recent years. Now, to take stock of where we are and what is known about gas hydrates, USGS has published two new fact sheets focused on methane hydrates. John Haines, Program Coordinator for CMGP and Acting Associate Director for the USGS Natural Hazards Mission Area, commented that, “These new fact sheets highlight the role that the USGS Gas Hydrates Project plays in advancing national and international understanding of natural methane hydrates in collaboration with critical partners like the U.S. Department of Energy. Our stakeholders will benefit from access to the clear, up-to-date information provided on these fact sheets.”
USGS Flood Experts Respond to High Water in Central, Northeastern U.S.
March 7—Crews from the USGS have been in the field for weeks measuring flooding in the Midwest and in the Mississippi River watershed, and more recently flooding and storm tides on the Northern Atlantic coast. During this string of intense storms, more than 100 USGS scientists and technicians were mobilized across the affected regions to keep the USGS’s streamgage network operational, perform on-site measurements of flooded rivers, install storm-tide and wave sensors prior to the nor’easter, and measure high-water marks as flood waters receded. A second nor’easter was affecting areas from Virginia to Maine on March 7, and was expected to bring heavy snow to some areas already impacted by the nor’easter that hit the area March 2–3. Coastal communities are just beginning to recover from the first nor’easter. Its intense winds and storm surge caused coastal erosion and tidal flooding in some states, leading to several deaths and leaving almost a million people without power.
Waterbirds at Risk in the Chesapeake Bay
March 1—Manmade structures built along Chesapeake Bay shorelines to protect against sea level rise, storm surge, and erosion have been found to negatively impact waterbirds, according to a USGS study. In many coastal regions, shorelines are “armored” with wooden, concrete or steel bulkhead walls or riprap borders that consist of piles of large stones or boulders. Shoreline armoring, however, can result in habitat loss and changes in food availability for many native coastal species as well as contribute to the spread of invasive species. USGS scientists looked at impacts to waterbirds, which include ducks, geese, shorebirds, marsh birds, seabirds and wading birds. Waterbirds can be indicators of overall ecosystem health and their declining numbers can cause cascading effects throughout the rest of the chain. “This research will help managers make informed decisions to preserve critical species and ecosystem functions while also protecting against sea level rise,” said USGS biologist Diann Prosser, who is the lead researcher on this study.
USGS Deploys Storm-Tide Sensors in Advance of Nor’Easter
March 1—USGS field crews deployed storm-tide and wave sensors from Maine to Delaware to track and study a Nor’easter. These sensors continuously measure wave height and tide levels and provide information on the timing, duration, and extent of flooding. Data is collected four times per second, providing a detailed picture of the storm. The information gathered will help federal and state officials, emergency managers, and coastal planners understand storm processes and ultimately build more resilient communities. “Nor’easters can cause higher storm tides than hurricanes in the Northeast and mid-Atlantic,” said USGS New York Water Science Center supervisory hydrologist Ronald Busciolano. “Many of the highest recorded tides in these areas were from these types of storms.”
February 28—The Asian tiger mosquito—carrier of such diseases as dengue, yellow fever, Rift Valley fever, Chikungunya, and Zika—appears to have vanished from Palmyra. Not native to the small atoll 1,000 miles south of Hawaii, Aedes albopict likely came to Palmyra during World War II. The military imported many other species as well, including the common black rat, whose blood fed many of the mosquitoes. In 2011, to help Palmyra recover from the ecological damage wreaked by the non-native rats, land managers implemented an aerial drop of rodenticide that quickly eradicated them. Without rats to feed on, the mosquitoes were left with only humans to bite. But rather than being bitten more, people eventually were not bitten at all. “Normally we mourn species losses, but without introduced rats and mosquitoes, Palmyra Atoll is as close to paradise as you could imagine,” explained lead author Kevin Lafferty, a USGS ecologist and an adjunct faculty member at UCSB.
Gas Hydrate from Offshore Korea
February 23—For several years the Korean Institute of Geoscience and Mineral Resources has hosted an international program for geoscience resources. The IS-Geo program draws together federal and private-sector professionals from the international community to discuss a range of specific geoscience and mineral topics. USGS participated in the final week of a three-week program on unconventional oil and gas resources, a week focused on gas hydrates. Discussion topics ranged from fundamental gas hydrate information about where gas hydrates occur in nature and how gas hydrates interact with a changing environment, all the way to engineering application issues related to extracting methane from gas hydrate as an energy resource.
Slow Slip Event on Kīlauea Volcano’s South Flank is Expected This Year
February 22—Can you guess when the next slow slip event will happen on Kīlauea Volcano's South Flank? As a hint, the last one was in October 2015, and before then, events occurred in May 2012, February 2010, and June 2007. If this seems like a pattern, you’re right. Slow slip events are sometimes called “slow earthquakes” or “episodic slip events.” They happen when a fault begins sliding, just like in a regular earthquake, but so slowly that it takes several days to finish instead of several seconds. At Kīlauea, slow earthquakes occur on the nearly flat-lying décollement fault that underlies the volcano's south flank at a depth of 6–8 km (4–5 mi). This is the same fault that was responsible for the magnitude-7.7 Kalapana earthquake in 1975.
Scientists Study the “Social Networks” of Wildlife
February 22—In the future of wildlife tracking, sea otters have their own social network. Whereas we might carry cell phones or tablets, each sea otter has a small, solar-powered tag clipped carefully to one of its flippers. When the sea otters gather to nap at the ocean’s surface, their tags boot up, and check in with one another. Who else did the sea otter interact with today, where, and when? Currently, USGS biologists use radio transmitters, binoculars, and high-powered spotting scopes to track sea otters from shore. USGS scientists have teamed up with the NASA to design two new types of wildlife-tracking tag. “We want the new tags to apply to a broad range of species, from polar bears to songbirds,” says Susan De La Cruz, a wildlife biologist and USGS lead on the project.
Rising Sea Levels Put Pacific Salt Marshes at Risk For Extinction
February 21—Climate change is dialing up the pressure on species around the world. Individual species aren’t the only ones at risk of extinction. In the case of Pacific coastal wetlands, an entire ecosystem type could be wiped out by a rise in the sea level, according to UCLA and USGS research published today in the journal Science. “The bottom line is, especially in California, most of the salt marsh is going to go away by 2100,” said Richard Ambrose, a UCLA professor of environmental health and co-author of the paper. “Some will go away by 2050.” The marshes also offer unique cultural, recreational, and educational opportunities. “These are places where people can fish, canoe, kayak and hike around the coast,” said Karen Thorne, lead author of the paper and a researcher with the USGS. “Wetlands are also great flood protection. After the stormy El Niño last winter, they acted like sponges to absorb that water.”
Laboratory Collaboration to Study Earthquake Hazards Off Southeast Alaska and Western Canada, March 12 https://marine.usgs.gov/news/archive.php#1236
Massachusetts Coastal Storms Impacts. March 6 https://marine.usgs.gov/news/archive.php#1234
Newspaper Story on Earthquake Hazards in Santa Rosa, California, Features Information from USGS Scientists, February 21 https://marine.usgs.gov/news/archive.php#1237
USGS Fields Tsunami Questions After Earthquake Off Kodiak, Alaska, February 20 https://marine.usgs.gov/news/archive.php#1222
False-Alarm Tsunami Alerts Across the U.S. East Coast, Gulf of Mexico, and Caribbean Prompt Calls to USGS, February 16 https://marine.usgs.gov/news/archive.php#1220
For all USGS Coastal and Marine Geology Program news, see: https://marine.usgs.gov/news/
For all USGS news, see: https://www.usgs.gov/news
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