Science Explorer
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Exploring: Islands
Rapid colonization of a Hawaiian restoration forest by a diverse avian community
Deforestation of tropical forests has led to widespread loss and extirpation of forest bird species around the world, including the Hawaiian Islands which have experienced a dramatic loss of forests over the last 200–800 years. Given the important role birds play in forest ecosystem functions via seed dispersal and pollination, a bird community's...
Minerals Yearbook, volume III, Area Reports—International—Latin America and Canada
The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows:Volume I, Metals and Minerals, contains chapters about virtually all metallic...
Trends and habitat associations of waterbirds using the South Bay Salt Pond Restoration Project, San Francisco Bay, California
Executive SummaryThe aim of the South Bay Salt Pond Restoration Project (hereinafter “Project”) is to restore 50–90 percent of former salt evaporation ponds to tidal marsh in San Francisco Bay (SFB). However, hundreds of thousands of waterbirds use these ponds over winter and during fall and spring migration. To ensure that existing waterbird...
Evaluation of social attraction measures to establish Forster’s tern (Sterna forsteri) nesting colonies for the South Bay Salt Pond Restoration Project, San Francisco Bay, California—2017 Annual Report
Forster’s terns (Sterna forsteri), historically one of the most numerous colonial-breeding waterbirds in South San Francisco Bay, California, have had recent decreases in the number of nesting colonies and overall breeding population size. The South Bay Salt Pond (SBSP) Restoration Project aims to restore 50–90 percent of former salt evaporation...
Most atolls will be uninhabitable by the mid-21st century because of sea-level rise exacerbating wave-driven flooding
Sea levels are rising, with the highest rates in the tropics, where thousands of low-lying coral atoll islands are located. Most studies on the resilience of these islands to sea-level rise have projected that they will experience minimal inundation impacts until at least the end of the 21st century. However, these have not taken into account the...
Titanium mineral resources in heavy-mineral sands in the Atlantic coastal plain of the southeastern United States
This study examined titanium distribution in the Atlantic Coastal Plain of the southeastern United States; the titanium is found in heavy-mineral sands that include the minerals ilmenite (Fe2+TiO3), rutile (TiO2), or leucoxene (an alteration product of ilmenite). Deposits of heavy-mineral sands in ancient and modern coastal plains are a...
Nearshore coastal bathymetry data collected in 2016 from West Ship Island to Horn Island, Gulf Islands National Seashore, Mississippi
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center, in cooperation with the U.S. Army Corps of Engineers, Mobile District, conducted bathymetric surveys of the nearshore waters surrounding Ship and Horn Islands, Gulf Islands National Seashore, Mississippi. The objective of this study was to establish base-level...
Aquatic vegetation responses to island construction (habitat restoration) in a large floodplain river
The Upper Mississippi River is maintained in its current navigable state through impoundments, dredging, and other engineering projects. These stressors, along with anthropogenic impacts and natural system processes, led to declines in aquatic vegetation and the loss of fish and wildlife habitat, with a major downturn the late 1980s and early...
The risk of rodent introductions from shipwrecks to seabirds on Aleutian and Bering Sea islands
Accidental introductions of rodents present one of the greatest threats to indigenous island biota, especially seabirds. On uninhabited remote islands, such introductions are likely to come from shipwrecks. Here we use a comprehensive database of shipwrecks in Western Alaska to model the frequency of shipwrecks per Aleutian and Bering Sea island,...
Geology and assessment of undiscovered oil and gas resources of the East Siberian Sea Basin Province, 2008
The East Siberian Sea Basin, which lies beneath the continental shelf east of the New Siberian Islands, is one of the better-known basins in a series of postorogenic (successor) basins in the East Siberian-Chukchi Sea region because of a reconnaissance network of seismic-reflection profiles and outcrops on nearby islands. In spite of the seismic...
Invasive rat control is an efficient, yet insufficient, method for recovery of the critically endangered Hawaiian plant hau kuahiwi (Hibiscadelphus giffardianus)
Biological invasions of rodents and other species have been especially problematic on tropical islands. Invasive Rattus rattus consumption of Hibiscadelphus giffardianus (Malvaceae; common Hawaiian name hau kuahiwi) fruit and seeds has been hypothesized to be the most-limiting factor inhibiting the critically endangered tree, but this has not been...
Comparison of estimators for monitoring long-term population trends in deer mice, Peromyscus maniculatus, on the California Channel Islands
Capture-recapture methods are commonly used to estimate abundance and density of wild animal populations. Although a variety of sophisticated analytical techniques are available to evaluate capture-recapture data, vertebrate monitoring programs often lack the resources (e.g., time, personnel, and/or analytical expertise) to apply these methods. As...
Quaternary sea-level history and the origin of the northernmost coastal aeolianites in the Americas: Channel Islands National Park, California, USA
Along most of the Pacific Coast of North America, sand dunes are dominantly silicate-rich. On the California Channel Islands, however, dunes are carbonate-rich, due to high productivity offshore and a lack of dilution by silicate minerals. Older sands on the Channel Islands contain enough carbonate to be cemented into aeolianite. Several...
Contaminants in tropical island streams and their biota
Environmental contamination is problematic for tropical islands due to their typically dense human populations and competing land and water uses. The Caribbean island of Puerto Rico (USA) has a long history of anthropogenic chemical use, and its human population density is among the highest globally, providing a model environment to study...
Partial migration of the nurse shark, Ginglymostoma cirratum (Bonnaterre), from the Dry Tortugas Islands
Nurse sharks have not previously been known to migrate. Nurse sharks of the Dry Tortugas (DRTO) mating population have a highly predictable periodic residency cycle, returning to the Dry Tortugas Courtship and Mating Ground (DTCMG) annually (males) or bi- to triennially (females) during the June/July mating season. For 23 years we have followed...
Plant and microbial biomarkers suggest mechanisms of soil organic carbon accumulation in a Mojave Desert ecosystem under elevated CO2
We investigated how properties of soil organic matter (SOM) were altered after 10 years exposure to elevated atmospheric CO2 concentration ([CO2]) in a Mojave Desert ecosystem, using plant and microbial biomarkers. We focused on roles of Larrea tridentata, the dominant evergreen shrub which form islands of fertility, and ...
Establishment of the exotic invasive Cuban treefrog (Osteopilus septentrionalis) in Louisiana
The Cuban treefrog, Osteopilus septentrionalis, is native to Cuba, the Bahamas, and the Cayman Islands, and is invasive in areas where it has been introduced and established in the Caribbean as well as Florida. Despite repeated occurrences in several states over many years, it was not believed that Cuban treefrogs had successfully established...
California State Waters Map Series — Offshore of Point Conception, California
IntroductionIn 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed...
Long Island South Shore Estuary Reserve Coordinated Water Resources Monitoring Strategy
Executive SummaryThe Long Island South Shore Estuary Reserve Coordinated Water Resources Monitoring Strategy (CWRMS) provides an overview of the water-quality and ecological monitoring within the Reserve and presents suggestions from stakeholders for future data collection, data management, and coordination among monitoring programs. The South...