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Enormous Caribbean Waves Before 1492
March 20—Geologists have discovered evidence that unusual seas detached living corals from a Caribbean reef and scattered them far inland, as boulders, during the last centuries before Columbus arrived. The new findings will reinforce precautions against coastal hazards, Caribbean tsunami specialists said. The coral boulders were found in the British Virgin Islands at Anegada—a low-lying island named by Columbus in 1493 and located behind a coral reef that faces the Puerto Rico Trench. One of the geologists, Brian Atwater of the USGS said, "We were astonished to find over 200 coral boulders scattered as much as one-third of a mile inland from the island's trenchward shore." He added, "Some are entire colonies of brain coral a few feet in diameter. All were likely emplaced during a sea flood sometime between the years 1200 and 1480."
Water Managers Explore New Strategies to Protect Fish in California's Bay Delta
March 13—The San Francisco Bay and Sacramento-San Joaquin River Delta is a 1,600-square-mile estuary and habitat for more than 500 species of wildlife. The delta is the central hub of California's water system. Despite efforts by local, state, and federal agencies to balance water deliveries and the delta's ecological health, the delta is failing to support sustainable populations of key species like the Chinook salmon and the delta smelt. In the face of ongoing drought and declining fish populations, regulators restricted pumping from the delta. To implement effective strategies that protect fish populations, water managers need detailed information on the stressors that affect their survival in the delta. In 2011 and 2012, USGS scientists applied acoustic telemetry to evaluate a project that steered fish toward a preferred migration path and could increase their chance of survival.
Growing the Right Coral for the Job: Fine Tuning Coral Nursery Techniques for Coral Reef Restoration
March 8—USGS research marine biologist Ilsa Kuffner, research oceanographer Lauren Toth, oceanographer Anastasios Stathakopoulos, and colleagues from NOAA and Mote Marine Tropical Laboratory in Florida published a research article in the journal Coral Reefs entitled, "Plasticity in skeletal characteristics of nursery-raised staghorn coral, Acropora cervicornis." The staghorn coral is a threatened species and is the primary focus of reef-restoration activities throughout Florida and the Caribbean. This study provides valuable new data demonstrating that the two most common rearing techniques used in offshore coral nurseries produce colonies with different skeletal characteristics. The results also indicate that variability in coral-calcification performance is genetically based. These results will be of great interest to coral-restoration practitioners, reef conservationists, governmental resource managers, and other scientists in the field of coral reef research and restoration.For more information: https://marine.usgs.gov/news/archive.php#1063.
The Challenge of Tracking Nutrient Pollution 2,300 Miles
March 6—Each spring, water flows approximately 2,300 miles down the Mississippi River, beginning its journey at Lake Itasca in northern Minnesota and emptying into the Gulf of Mexico. Along the way, streams and rivers accumulate nutrients that run off the land and into the waterways, and eventually these nutrients enter the Gulf of Mexico. Spring pulses of nutrients to the Gulf contribute to the second largest hypoxic—or low oxygen—zone in the world. In 2016, the estimated size of the hypoxic zone in the Gulf of Mexico was 5,898 square miles, approximately the size of Connecticut. "Fertilizers used on crops, air pollution, and manure are some of the major sources of nitrogen transported from the Mississippi River Basin to the Gulf of Mexico," said Michael Woodside, a hydrologist with the USGS.
Monitoring Alaska's Remote and Restless Bogoslof Volcano
March 3—Bogoslof volcano, located in the Aleutian Islands about 98 kilometers (61 miles) northwest of Dutch Harbor/Unalaska, is in an active eruption sequence that began in mid-December 2016 and continues today. Eruptive activity has been dominated by a series of explosive events originating from below sea level and lasting from about 30 to 60 minutes each. The explosions can put volcanic ash to altitudes exceeding 30,000 feet, resulting in drifting clouds of ash that threaten not only local air traffic, but also wide-body jets flying between North America and Asia. Bogoslof is not monitored by a local geophysical network, which limits scientists' ability to forecast and closely track activity at this volcano. The USGS Alaska Volcano Observatory (AVO) is using seismic and infrasound (airwave) sensors on neighboring Umnak and Unalaska Islands to monitor activity. In addition, AVO is using satellite imagery and information from the Worldwide Lightning Location Network to detect activity and track any drifting clouds of ash.
Sediment Flows into Galveston Bay Studied to Help Understand Health of Watershed
February 22—A better understanding of sediment and freshwater flow into Galveston Bay is now available from a new USGS report, conducted in cooperation with the Texas Water Development Board and the Galveston Bay Estuary Program. Galveston Bay is an important watershed that provides the public with food and economic security, as well as a place for recreational activities. The health of this ecosystem is reliant on the quality and quantity of freshwater streamflow and sediment from the land. Flows can be influenced by alterations in the river course, such as withdrawals and diversions. With population and water demand projected to increase, the ability to provide adequate flows to coastal ecosystems presents a resource-management challenge that requires improving the current understanding of freshwater flows.
Nadine Golden is Acting Deputy Director of Pacific Coastal and Marine Science Center
February 22—February 22 - Director Guy Gelfenbaum of the USGS Pacific Coastal and Marine Science Center (PCMSC) in Santa Cruz, California, announced on February 16 that Nadine Golden will be the Center's Acting Deputy Director. Golden has an undergraduate degree from the University of California, Berkeley, and a Masters in geography from San Francisco State University. She has been with the PCMSC since 2004 and has played a major role in GIS analysis, accuracy assessment, metadata, data management, and archives for the California Seafloor Mapping Program and Marine Geomorphology, Evolution, and Habitats project. Golden has helped lead PCMSC's data-management group and has facilitated center scientists' access to and use of ScienceBase to meet data-publishing requirements. Her history of helping PCMSC accomplish its science goals makes her a valuable addition to the center management team.
Hurricane Sandy Storm Impacts - March 6
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