Florida Manatees Likely to Persist for At Least 100 Years
April 11—Florida’s iconic manatee population is highly likely to endure for the next 100 years, so long as wildlife managers continue to protect the marine mammals and their habitat, a new study by the USGS and the Florida Fish and Wildlife Research Institute has found. The study, conducted by a team of veteran manatee scientists, estimated there is less than a one-half of one percent chance that either Florida’s Atlantic or its Gulf of Mexico manatee population could fall to as few as 500 adults—the level that could imperil Florida manatees’ long-term survival. “Today the Florida manatees’ numbers are high. Adult manatees’ longevity is good, and the state has available habitat to support a population that is continuing to grow,” said USGS research ecologist Michael C. Runge.
Mapping the Effects of Storm Flow on a Wetland-Restoration Site in South San Francisco Bay
April 6—USGS scientists mapped the bottom of Alviso Slough in San Francisco Bay March 27–29 to measure scour caused by heavy storms. In the largest wetland-restoration project on the U.S. West Coast, the South Bay Salt Pond Restoration Project is breaching levees to restore tidal flow to former commercial salt ponds. Managers worry that strong water flows—from levee breaches, storm runoff, or opening gates that route water into restored ponds—could stir up bottom sediment and re-mobilize mercury washed downriver from a now-closed mine. River flows in January and February were the highest since 1998. USGS, which maps the slough regularly to monitor effects of levee breaches and seasonal variability, conducted the extra survey to capture impacts of the high flows. USGS scientists will use the data to improve computer simulations developed to forecast the effects of continued restoration and sea-level rise.
Bogoslof Volcano, Alaska: Ongoing Eruption through the Bering Sea
March 30—Hawaiʻi is not the only island in the United States with an ongoing eruption involving hot lava and cold water. Let’s go north to Alaska where scientists have been tracking an intermittent eruption of lava through water surrounding a small island volcano in the southern Bering Sea. On December 21, 2016, the volcano burst to life sending clouds of ash and water vapor towering into the sky. Pilots were the first to see the eruption, calling in reports to air traffic control. Soon, scientists with the Alaska Volcano Observatory and the National Weather Service saw the eruption cloud on satellite imagery. Using information about winds aloft, warnings of the forecast ash cloud path went out to airlines.
Brown Bears, Sea Otters, and Seals, Oh My!—Unexpected Interactions on the Katmai Coast
March 30—Grant Hilderbrand, Chief of the Marine Ecosystems Office, USGS Alaska Science Center, gave a public lecture on March 30, 2017, at the USGS offices in Menlo Park, California. He highlighted ongoing research on brown bears on the coast of the Katmai National Park in Alaska, including observations from video collars deployed on brown bears and implications for population health and species adaptability.
Sex-Shifting Fish: Growth Rate Could Determine Sea Lamprey Sex
March 28—Unlike most animals, sea lampreys, an invasive, parasitic species of fish damaging the Great Lakes, could become male or female depending on how quickly they grow, according to a USGS study published today. Scientists with the USGS and Michigan State University, funded by the Great Lakes Fishery Commission, found that slower sea lamprey growth rates during the larval phase of development may increase the odds of sea lampreys becoming male. This discovery could be a critical step in developing advanced technologies to control sea lamprey. “Remarkably, we didn’t set out to study sex determination in sea lampreys—we were planning to study environmental effects on growth rates only,” said Nick Johnson, a USGS scientist and the lead author of the study. “We were startled when we discovered that these data may also reveal how sex is determined because mechanisms of sex determination in lamprey are considered a holy grail for researchers.”
Disappearing Beaches: Modeling Shoreline Change in Southern California
March 27—Using a newly-developed computer model called “CoSMoS-COAST” (Coastal Storm Modeling System – Coastal One-line Assimilated Simulation Tool) scientists predict that with limited human intervention, 31 to 67 percent of Southern California beaches may become completely eroded (up to existing coastal infrastructure or sea-cliffs) by the year 2100 under scenarios of sea-level rise of 1 to 2 meters. “Beaches are perhaps the most iconic feature of California, and the potential for losing this identity is real. The effect of California losing its beaches is not just a matter of affecting the tourism economy. Losing the protecting swath of beach sand between us and the pounding surf exposes critical infrastructure, businesses, and homes to damage,” said lead author of the study, Sean Vitousek, who was a post-doctoral fellow at the U.S. Geological Survey when he conducted this study.
Related: Study Forecasting Erosion of Southern California Beaches Draws Widespread Media Attention https://marine.usgs.gov/news/archive.php#1077.
History of Abrupt Sinking of the Seal Beach Wetlands: New Study Reveals Past Quakes along Fault and Offers Glimpse into the Future
March 20—A new collaborative study shows evidence of prior abrupt sinking of the wetlands near Seal Beach, California, caused by ancient earthquakes that shook the area at least three times in the past 2,000 years, according to researchers. “Imagine a large earthquake—and it can happen again—causing the Seal Beach wetlands to sink abruptly by up to 3 feet. This would be significant, especially since the area already is at sea level,” said Matthew Kirby, California State University Fullerton (CSUF) professor of geological sciences. Former USGS geologist and CSUF alumnus Robert Leeper led the study with Kirby and Brady Rhodes, CSUF professor emeritus of geological sciences. Leeper’s master's thesis is based on the research findings. “These research findings have important implications in terms of seismic hazard and risk assessment in coastal Southern California and are relevant to municipal, industrial, and military infrastructure in the region,” said Leeper.
USGS Scientists Offer Career Advice to Students at University of California, Santa Cruz
March 20—Students considering careers in Earth and ocean sciences gained valuable information from USGS research scientists Amy East and Melissa Foley at a March 8 event at the University of California, Santa Cruz. East, Foley, and eight more scientists on the GEODES (Geoscientists Encouraging Openness and Diversity in the Earth Sciences) Career Panel briefly described their career paths and then joined small groups of students for lively conversations that lasted more than 2 hours. Both graduate and undergraduate students attended the event, sponsored by the student organization GEODES.
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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