Mission Areas

Ecosystems

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Filter Total Items: 455
USGS science for a changing world logo
Date Published: February 26, 2016

Functional relationships among aquatic species for conserving and restoring aquatic community function.

USGS science for a changing world logo
Date Published: February 26, 2016

The Oregon Cooperative Unit, graduate students, and a group of U.S. and international collaborators are conducting long-term research on the Adélie penguin on Ross Island, Antarctica. This species depends on sea ice (obligate) and in some regions of Antarctica is being affected by climate change’s influence on sea ice patterns.

USGS science for a changing world logo
Date Published: February 26, 2016

Improving fish passage is vital for restoring populations of salmon and other migratory fish.

USGS science for a changing world logo
Date Published: February 26, 2016

Many species of sea turtle are endangered. Conservation of these species is complicated by their complex life history, the broad spatial distribution of different life stages, and their migratory nature. Monitoring programs track general status of populations and evaluate the effect of management actions on species conservation.

USGS science for a changing world logo
Date Published: February 26, 2016

Rivers are the conduit between inland waters and the oceans for fish, nutrients, and sediments

Life on the Edge: Can Corals Thriving in Mangroves Provide Insights into Climate Change?
Date Published: February 26, 2016

On an island in the U.S. Virgin Islands, USGS scientists discover corals are seeking refuge from climate change in mangroves.

Invasive snakehead fish - WARC
Date Published: February 26, 2016

USGS scientists study the mechanisms of aquatic species invasions across the South Atlantic Landscape Conservation Cooperative (SALCC) with the help of the Nonindigenous Aquatic Species Database (NAS).

Cactus in the desert
Date Published: February 26, 2016

Deserts are areas of the country which receive less than 10 in (250 mm) annual precipitation. In the United States, we have four distinct major deserts. Three are “hot deserts” because they receive precipitation in the summer months (Mojave, Sonoran, Chihuahuan) and one “cold desert” because it receives precipitation during the winter (Great Basin).

Ecology of and Control Strategies for Invasive Burmese Pythons (Python molurus bivitattus) in the Greater Everglades
Date Published: February 26, 2016

Telemetry tracking of captured pythons reveals movement patterns of the invasive Burmese python in the Greater Everglades, information that managers can use to prioritize python control efforts.

Lightning storm over the Beaverjack Fire seen from Hells Half Lookout on the Bitterroot National Forest, ID
Date Published: February 26, 2016

Ecological Stressors are physical, chemical, and biological factors that impact the condition and integrity of ecosystems and can change the trajectories of species and ecosystems. Stressors can be natural (fire, storms, insect outbreaks), or anthropogenic (e.g., climate change, fire, energy development).

Birds eating in a wetland
Date Published: February 26, 2016

USGS research on wetlands spans the range from freshwater alpine lakes in the Western United States to salt marshes along the Gulf; from the coastline of Alaska to the Southeastern US, and from vernal pools to the Great Lakes. Our scientists conduct research at local, national and international scales.

Sea Turtle Habitat Use at Buck Island Reef National Monument, U.S. Virgin Islands
Date Published: February 26, 2016
Status: Active

USGS researchers tag and track endangered and threatened sea turtles to inform adaptive management strategies in marine protected areas.

Filter Total Items: 544
Year Published: 2010

Characteristics of fall chum salmon spawning habitat on a mainstem river in Interior Alaska

Chum salmon (Oncorhynchus keta) are the most abundant species of salmon spawning in the Yukon River drainage system, and they support important personal use, subsistence, and commercial fisheries. Chum salmon returning to the Tanana River in Interior Alaska are a significant contribution to the overall abundance of Yukon River chum salmon and an...

Burril, Sean E.; Zimmerman, Christian E.; Finn, James E.
Characteristics of fall chum salmon spawning habitat on a mainstem river in Interior Alaska; 2010; OFR; 2010-1164; Burril, Sean E.; Zimmerman, Christian E.; Finn, James E.

Year Published: 2010

Alaska’s changing fire regime - Implications for the vulnerability of its boreal forests

A synthesis was carried out to examine Alaska’s boreal forest fire regime. During the 2000s, an average of 767 000 ha·year–1 burned, 50% higher than in any previous decade since the 1940s. Over the past 60 years, there was a decrease in the number of lightning-ignited fires, an increase in extreme lightning-ignited fire...

Kasischke, Eric S.; Verbyla, David L.; Rupp, T. Scott; McGuire, A. David; Murphy, Karen A.; Jandt, R.; Barnes, Jennifer L.; Hoy, E.; Duffy, Paul A; Calef, Monika; Turetsky, Merritt R.

Year Published: 2010

Resilience of Alaska’s boreal forest to climatic change

This paper assesses the resilience of Alaska’s boreal forest system to rapid climatic change. Recent warming is associated with reduced growth of dominant tree species, plant disease and insect outbreaks, warming and thawing of permafrost, drying of lakes, increased wildfire extent, increased postfire recruitment of deciduous trees, and...

Chapin, F.S.; McGuire, A. David; Ruess, Roger W.; Hollingsworth, Teresa N.; Mack, M.C.; Johnstone, J.F.; Kasischke, E.S.; Euskirchen, E.S.; Jones, J.B.; Jorgenson, M.T.; Kielland, K.; Kofinas, G.; Turetsky, M.R.; Yarie, J.; Lloyd, A.H.; Taylor, D.L.

Year Published: 2010

Calibrating recruitment estimates for mourning doves from harvest age ratios

We examined results from the first national-scale effort to estimate mourning dove (Zenaida macroura) age ratios and developed a simple, efficient, and generalizable methodology for calibrating estimates. Our method predicted age classes of unknown-age wings based on backward projection of molt distributions from fall harvest collections to...

Miller, David A.; Otis, David L.

Year Published: 2010

Modeling the Effects of Mortality on Sea Otter Populations

Conservation and management of sea otters can benefit from managing the magnitude and sex composition of human related mortality, including harvesting within sustainable levels. Using age and sex-specific reproduction and survival rates from field studies, we created matrix population models representing sea otter populations with growth rates of...

Bodkin, James L.; Ballachey, Brenda E.
Modeling the Effects of Mortality on Sea Otter Populations; 2010; SIR; 2010-5096; Bodkin, James L.; Ballachey, Brenda E.

Year Published: 2010

The changing effects of Alaska’s boreal forests on the climate system

In the boreal forests of Alaska, recent changes in climate have influenced the exchange of trace gases, water, and energy between these forests and the atmosphere. These changes in the structure and function of boreal forests can then feed back to impact regional and global climates. In this manuscript, we examine the type and magnitude of the...

Euskirchen, E.S.; McGuire, A. David; Chapin, F.S.; Rupp, T.S.

Year Published: 2010

Recovery of sediment characteristics in moraine, headwater streams of northern Minnesota after forest harvest

We investigated the recovery of sediment characteristics in four moraine, headwater streams in north-central Minnesota after forest harvest. We examined changes in fine sediment levels from 1997 (preharvest) to 2007 (10 years postharvest) at study plots with upland clear felling and riparian thinning, using canopy cover, proportion of...

Vondracek, Bruce C.; Merten, Eric C.; Hemstad, Nathaniel A.; Kolka, Randall K.; Newman, Raymond M.; Verry, Elon S.

Year Published: 2010

Abdominally implanted transmitters with percutaneous antennas affect the dive performance of Common Eiders

Implanted transmitters have become an important tool for studying the ecology of sea ducks, but their effects remain largely undocumented. To address this, we assessed how abdominally implanted transmitters with percutaneous antennas affect the vertical dive speeds, stroke frequencies, bottom time, and dive duration of captive Common Eiders (...

Powell, Abby N.; Latty, Christopher J.; Hollmén, Tuula E.; Petersen, Margaret R.; Andrews, Russel D.

Year Published: 2010

Comparative morphology among northern populations of breeding Cooper's Hawks

Few studies at a broad geographical scale have characterized intraspecific variation in morphology of woodland hawks in the genus Accipiter. From 1999 to 2007 we investigated morphological variation in large samples of live Cooper's Hawks (A. cooperii) nesting in four study areas: coniferous woodland around Victoria, British Columbia, Canada...

Rosenfield, Robert N.; Rosenfield, Laura J.; Bielefeldt, John; Murphy, Robert K.; Stewart, Andrew C.; Stout, William E.; Driscoll, Timothy G.; Bozek, Michael A.

Year Published: 2010

Scale-dependent mechanisms of habitat selection for a migratory passerine: an experimental approach

Habitat selection theory predicts that individuals choose breeding habitats that maximize fitness returns on the basis of indirect environmental cues at multiple spatial scales. We performed a 3-year field experiment to evaluate five alternative hypotheses regarding whether individuals choose breeding territories in heterogeneous landscapes on the...

Donovan, Therese M.; Cornell, Kerri L.

Year Published: 2010

Habitat selection and abundance of young-of-year smallmouth bass in north temperate lakes

Habitat use during early life history plays an important role in the ecology of smallmouth bass Micropterus dolomieu in north temperate lakes. The highest levels of mortality occur during the first year of life, and the habitat selected probably affects mortality. We used resource selection functions and abundance data from two northern...

Brown, Peter James; Bozek, Michael A.

Year Published: 2010

Assessing effects of water abstraction on fish assemblages in Mediterranean streams

1. Water abstraction strongly affects streams in arid and semiarid ecosystems, particularly where there is a Mediterranean climate. Excessive abstraction reduces the availability of water for human uses downstream and impairs the capacity of streams to support native biota. 2. We investigated the flow regime and related variables in six river...

Benejam, Lluis; Angermeier, Paul L.; Munne, Antoni; García-Berthou, Emili

Filter Total Items: 453
September 7, 2008
Permanent Site: J1 West Transect; Depth: 9.2 Meters (30.2 Feet); Distance from river mouth: 6.6 Kilometers (4.1 Miles) east; Pre/Post Dam Removal: 1 year pre-dam removal; Lat/Long: 48.13607725,-123.48002186; Site Description: This site is medium depth. Substrates is a gravel/cobble/sand mixture with an occasional boulder. Seaweed is abundant, especially three-ribbed kelp Cymathere triplicata (0:...
September 7, 2008
Permanent Site: J1 East Transect; Depth: 9.5 Meters (31.2 Feet); Distance from river mouth: 6.7 Kilometers (4.1 Miles) east; Pre/Post Dam Removal: 1 year pre-dam removal; Lat/Long: ; Site Description: This site is medium depth. Substrates is a gravel/cobble/sand mixture with an occasional boulder. Seaweed is abundant, especially three-ribbed kelp Cymathere triplicata (0:21, 1:06 seconds) and the...
August 24, 2008
Random Site: 5SM18 West Transect; Depth: 6.1 Meters (20 Feet); Distance from river mouth: 4.5 Kilometers (2.8 Miles) east; Pre/Post Dam Removal: 3 years pre-dam removal; Lat/Long: 48.13592923,-123.51082988; Site Description: This is a shallow site. Sediment is a gravel/sand mixture. Red, green and brown seaweed is abundant. Six species of browns were recorded including perennial seaweed...
August 24, 2008
Random Site: 5SM18 East Transect; Depth: 6.7 Meters (22.0 Feet); Distance from river mouth: 4.5 Kilometers (2.8 Miles) east; Pre/Post Dam Removal: 3 years pre-dam removal; Lat/Long: 48.1357869,-123.5095144; Site Description: This is a shallow site. Sediment is a gravel/sand mixture. Red, green and brown seaweed is abundant. Six species of browns were recorded including bull kelp Nereocystis...
Photo of Elizabeth Lake when it used to be a popular fishing spot in southern California.
July 22, 2008
Elizabeth Lake was about a mile long and 1/4 mile wide. It used to be a popular fishing spot in southern California. Almost all of the turtles living in a southern California lake died following a large fire and years of drought, according to a new USGS report.
Duck with various brown colored feathers
February 10, 2008
The USGS conducts surveillance and research nationwide on wildlife diseases that could be harmful to domestic animals and humans.
Nile perch harvest, Uganda
2007 (approx.)
Packing harvest of Nile Perch from Lake Victoria, Uganda.
Subalpine meadow near Deer Park campground, Washington
August 22, 2007
Subalpine meadow near Deer Park campground on the Olympic Peninsula in Washington. The range of trees in subalpine areas may shift in elevation with climate change. Treeline elevation shifts may be difficult to predict in a changing climate because warming may aid in uptake and use – or assimilation – of carbon, increasing tree establishment, or may exacerbate drought conditions, reducing carbon...
Arctic Sand Lance
2007 (approx.)
Arctic sand lance taken by bottom trawl in the eastern Chukchi Sea.
Tamarisk stem cross-section cut 2.8 m below the ground surface showing how sediment deposition is dated using tree rings.
2006 (approx.)
Tamarisk stem cross-section cut 2.8 m below the ground surface showing how sediment deposition is dated using tree rings. Following initial burial of 68 cm in 1969, ring-width decreased, vessel size increased, and annual transitions became less distinct. After a second burial by 41 cm in 1972, annual transitions became indistinguishable.