Wetland and Aquatic Research Center

This black-bellied salamander (Desmognathus quadramaculatus) was found in the Citico Creek Wilderness, Cherokee National Forest, Tennessee.

A queen angelfish peers through the safety of the mangrove roots across the rich colors and textures of corals, sponges, urchins, and algae. Queen angelfish feed almost exclusively on sponges, which are abundant in these mangroves.

An aerial view of coastal marshes along Bayou Dufrene, southwest of the town of Dulac in Louisiana's Terrebonne Basin.

USGS researcher collects data on manatee in Florida spring.

Brown Marsh observed in southeastern Terrebonne Basin, La

Manatee swims in a Florida spring

Two manatees with radio transmitters attached

To understand how changes in rainfall and temperature might affect coastal wetlands in the northern Gulf of Mexico, USGS researchers conducted field studies at 10 estuaries in five states (Texas, Louisiana, Mississippi, Alabama, and Florida). The fieldwork took place in a variety of coastal wetland types, including mangroves, marshes, and salt flats.

Prescribed burn

For nearly four decades, the U.S. Geological Survey's Sirenia Project has been committed to understanding the biology and ecology of the West Indian manatee to aid managers in actions that could best help the population. To do this, USGS manatee researchers rely on a variety of tools and techniques.

Prescribed burn

A lionfish floating in blue water. Photo: Richard Whitcombe. (Permission provided by photographer)

Blue Shiner, Cyprinella caerulea

A great blue heron standing in the marsh at Merritt Island National Wildlife Refuge near the Kennedy Space Center.

Red mangrove trees fringe the shoreline of a bay in Hurricane Hole, U.S. Virgin Islands. 

Wetlands Reserve Program site in Morehouse Parish, Louisiana.  Green tree frogs rest on a Wetlands Reserve Program easement boundary sign in Morehouse Parish, Louisiana.

Live Lophelia pertusa is white because the calcium carbonate skeleton shows through the nonpigmented coral tissue. Dead coral is soon covered in a brown biofilm. The red-orange squat lobster (Eumunida picta) in the center of the photo is prepared to catch its dinner.

Wetlands Reserve Program site in Natchitoches Parish, Louisiana.  Ten years ago, this landowner worked with the USDA Natural Resources Conservation Service through the Wetlands Reserve Program to design and construct this slough as part of a plan to restore this field’s natural wetland hydrology.

Wetlands Reserve Program site in St. Landry Parish, Louisiana.  Changes in a local river resulted in the landowner’s fields flooding on a regular basis. The landowner worked through the USDA Natural Resources Conservation Service to restore his fields to their natural wetland state.

A laboratory preparation of a Oaxaca Cave Sleeper specimen shows the absence of eyes in this newly identified cavefish species. Credit: Stephen J. Walsh, USGS

This Oaxaca Cave Sleeper is one of thirteen specimens collected from a cave beneath a reservoir on Mexico's Tonto River. It lacks eyes, is unpigmented, and has sensory adaptations characteristic of fish that live in total darkness. Thuis is the holotype, the example used to describe and name this newly identified species. Credit: Howard L. Jelks and Stephen J. Walsh, USGS

Frosted flatwoods salamander in St. Marks National Wildlife Refuge, Florida

Frosted flatwoods salamander, St. Marks National Wildlife Refuge, Florida

The pike killifish, native to Mexico and Central America, was one of 13 nonnative fish species that biologists discovered during the two-day Fish Slam in Big Cypress National Preserve, March 22 and 23, 2017.

The sailfin catfish is one of 13 species of nonnative fish that biologists discovered during the Fish Slam in Big Cypress National Preserve, March 23, 2017.

Vegetation assessments are part of an effort to produce seamless, consistent, and high resolution landcover data for the northern portion of the western gulf coastal plain. This geography was once dominated by tallgrass prairie and has undergone dramatic change with less than 1% of this natural habitat in existence.

Tallgrass prairie provides a suite of ecosystem services including enhancing beneficial insect and pollinator populations, improving water quality, sequestering carbon, and reducing runoff and erosion. Many of the remaining remnants are along the coastal fringes of the historic range and vulnerable to sea level rise. Due to the vast benefits associated with this diverse, productive, and threatened ecosystem, conservation entities across the Western Gulf Coastal Plain are working toward a collaborative, strategic, landscape scale approach to conservation planning.

Our work will provide baseline data to enhance the ability of decision makers to communicate, prioritize, and implement restoration activities and other habitat enhancement actions associated with water sheds within this geography.

Satellite images of the same wetland taken in 2008 and 2016 show a wetland restoration project has produced some gains in marsh area.

Researchers collected data from 21 different observations between 1932 and 2016 (black dots) and used statistical analysis to chart the rate of loss that most closely tracks those observations. That solid red line shows that Louisiana's coastal wetlands declined sharply up until the 1970s, and continue to decline, but at a slower rate. Though some recent observations lie above the red line, earlier losses strongly influence the historical trend, which still shows a decline. There is a 95% likelihood that the actual trend lies within the dotted blue lines.

An aerial view of southeast Louisiana coastal marshes. 

This map shows the historic trend in wetland losses, with early losses in red and the most recent ones in purple.

Graph of land area change rate in coastal Louisiana from 1932–2016.  The red line approximates the long-term land area change rate. 95 out of 100 statistical analyses would produce a very similar trend (dotted blue lines). Credit: USGS