Mission Areas


Mission Areas L2 Landing Page Tabs

The Ecosystems Mission Area provides impartial science information and tools to the Nation’s natural resource managers, with particular focus on the science needs of the Department of the Interior (DOI) and DOI bureaus to manage species, lands and priority ecosystems; fulfill treaty obligations; respond to and reduce threats to natural resources; and manage mineral and energy resources.


Check out our Cool Tools for Hot Topics!
Filter Total Items: 745
Date published: April 1, 2019
Status: Active

Ecological flow needs of freshwater mussels

Streamflow characteristics are rapidly changing in response to climate variability, water management practices, and a variety of other human water demands.  Alterations in water quantity can have direct impacts on aquatic organisms (e.g., stranding, displacement, disruption of spawning), and can be especially detrimental to organisms with limited mobility.  Freshwater mussels are one such...

Date published: April 1, 2019
Status: Active

Metabarcoding of stomach contents from the Round Goby (Negobius melanostromus) in Pennsylvania

The Round Goby, Neogobius melanostomus, is a small benthic fish native to the Sea of Azov, the Caspian Sea, the Black Sea and the Sea of Marmara. The first round goby found in the Pennsylvania waters was in 1996. Since then, round gobies are now the dominant benthic fish in many of the tributary streams in the Pennsylvanian waters of Lake Erie, including French Creek. French Creek is...

Contacts: Deborah D Iwanowicz, Jay Stauffer
Date published: March 29, 2019
Status: Active

Evaluation and Development of Fish Passage Structures and Technologies

Dams can be found in just about every major river, and for good reason.  Society has received many benefits like flood control, hydropower, water supply storage, and places to recreate.  However, many fish and other life in our rivers can’t swim around these barriers.  Often, the best spot for a fish to live and reproduce is out of reach because they can’t pass by a dam.  This has not gone...

Date published: March 29, 2019
Status: Active

Improving ecological flow science in the mainstem Delaware through WaterSMART

Demand for freshwater is increasing with human population growth and is exacerbated by water management practices, climate variability, and land use alternation.  Ecological flow science attempts to understand flows necessary to support aquatic organisms so that managers can balance these with diverse human water demands.  A primary focus of the USGS Northern Appalachian Research Laboratory (...

Date published: March 29, 2019
Status: Active

Assessing the effects of chloride exposure on aquatic organisms

Increased salinization of freshwater systems is a growing concern, and can be attributed to a variety of factors including climate change, land-use change, agricultural practices, road de-icing, and brines released from fossil fuel extraction.  Effects of increased salinization on aquatic organisms is little understood and may be vastly different among species and among different life stages...

Date published: March 29, 2019
Status: Active

Development of fine-scale temperature models in the Delaware River: Application to predictive temperature modeling, decision support tools, and ecosystem services

Temperature is a primary driver of biological and ecological processes, and in rivers and streams influences distribution, reproduction, and behavior of aquatic species.  USGS Northern Appalachian Laboratory (NARL) researchers are working with resource managers in the Delaware River Basin and collaborators at USGS Fort Collins Science Center to predict and model riverine temperature,...

Date published: March 26, 2019
Status: Active

Identification of Hydrologic Controls on Coastal Spartina patens Marshes and Optimal Hydrological Conditions for Sustainable Mottled Duck Habitat

Mottled ducks rely on the coastal marshes of the Texas Chenier Plain, which are considered among the most critically endangered habitats in the United States. USGS scientists are evaluating what might be contributing to the degradation of high-quality mottled duck habitat to better understand the causes of habitat loss and subsequently mitigate those losses.

Date published: March 26, 2019
Status: Active

The Nonindigenous Aquatic Species Alert Risk Mapper (ARM)

The Nonindigenous Aquatic Species (NAS) program has developed a new tool, the NAS Alert Risk Mapper (ARM), to characterize waterbodies in the conterminous U.S. and Hawaii at potential risk of invasion from a new nonindigenous species sighting.

Date published: March 26, 2019
Status: Active

Defining Native Ranges of U.S. Inland Fishes

Understanding the native versus non-native range of a species can provide useful information about dispersal, population distribution patterns, and human mediated movement across hydrologic barriers. The USGS Nonindigenous Aquatic Species (NAS) Program is working with partners to define native ranges of inland fishes in the United States to help identify which species should be included in the...

Date published: March 26, 2019
Status: Active

Population Ecology of Florida Manatees

USGS is working with partners to understand how the federally protected Florida manatee population changes over time and responds to threats.

Date published: March 22, 2019
Status: Active

Fall Survival of American Woodcock on Cape May, NJ

The American woodcock is a popular game bird in much of eastern North America. The woodcock population declined between 1968- 2000 at an annual rate of 2.3% in the Eastern region and 1.6% in the Central region. Estimated annual survival of woodcock banded in the Eastern region was estimated to be 0.354 for the period 1967-74. Estimates for the migration period, a period when substantial...

Contacts: Daniel McAuley
Date published: March 19, 2019
Status: Active

Pre-listing Science Support in the Northeast

The background information required to support listing decisions is not always current or available, and additional information or tools to model potential future condition can greatly improve the confidence in Species Status Assessments. We are working closely with multiple partners to provide updated information, model potential outcomes, and identify key uncertainties relevant to amphibian...

Filter Total Items: 150
Date published: May 2, 2018

DATA RELEASE - Population dynamics of humpback chub, rainbow trout and brown trout in the Colorado River in its Grand Canyon Reach: modelling code and input data

These data were compiled to fit an integrated population model of brown trout in the Glen Canyon reach of the Colorado River and test hypotheses regarding the driver of brown trout population dynamics. Also, data were compiled as inputs for a model to simulate population dynamics and species interactions among brown trout, rainbow trout, and humpback chub in the Colorado River.

Date published: April 27, 2018

North American Breeding Bird Survey Dataset

The North American Breeding Bird Survey dataset contains avian point count data for more than 700 North American bird taxa (species, races, and unidentified species groupings).  These data are collected annually during the breeding season, primarily June, along thousands of randomly established roadside survey routes in the United States and Canada.

Date published: April 16, 2018

Occurrence of Chlamydia sp in apparently healthy birds associated with a mortality event caused by chlamydiosis: Data

These data sets are is a compilation of bird and environmental samples obtained from 6 sites in Maricopa County, Arizona on the dates shown. Sites were only visited and sampled if they had Rosy-cheeked lovebirds coming to bird feeders at the location and with the permission of the property owner. Two swab samples were obtained from each captured bird and 3 swab samples were collected from the...

Date published: April 13, 2018

DATA RELEASE & MODEL - Continuous Detection PIT Array - Data & Model

These data represent a set of capture histories of rainbow trout captured in the Colorado River and(or) detected on the multiplexer array in the Little Colorado River.

Date published: April 6, 2018

DATA RELEASE - Remote sensing derived maps of tamarisk (2009) and beetle impacts (2013) along 412 km of the Colorado River in the Grand Canyon, Arizona - Data

These data are aerial image-derived, classification maps of tamarisk in a riparian zone of the Colorado River. Two maps are published: 1) a classification of tamarisk from a 0.2 m resolution multispectral image dataset acquired in May 2009, and 2) a classification of tamarisk impacted by the tamarisk beetle from a 0.2 m resolution multispectral image dataset acquired in May 2013.

Date published: April 5, 2018

DATA RELEASE - Landscape-scale wildlife species richness metrics - Data

These raster data represent the results of a case study in Arizona on how vertebrate richness metrics can be used with existing state and federal guidance in wind and solar energy facility siting. Each of the four geodatabases contain eight native terrestrial wildlife group models in Arizona: all vertebrates, amphibians, reptiles, birds, mammals, bats, raptors and long-distance migratory birds...

Date published: April 5, 2018

Corallimorph Invasion Palmyra: Data

In 2007, a phase shift from corals to corallimorpharians (CM) was documented at Palmyra Atoll, Line Islands, centered around a shipwreck. Subsequent surveys revealed CM to be overgrowing the reef benthos, including corals and coralline algae, potentially placing coral ecosystems in the atoll at risk. This prompted the U.S. Fish and Wildlife Service, the lead management agency of the atoll,...

Date published: April 2, 2018

Northern Sea Otter Aging Criteria: data

Measurement of skull ossification patterns is a standard method for aging various mammalian species and has been used to age Russian, Californian, and Alaskan sea otter populations. Cementum annuli counts have also been verified as an accurate aging method for the Alaskan sea otter population. In this study, cementum annuli count results and skull ossification patterns were compared as...

Date published: March 13, 2018

Wildlife Health Information Sharing Partnership – event reporting system (WHISPers)

The NWHC developed the Wildlife Health Information Sharing Partnership – event reporting system (WHISPers) to increase public awareness of wildlife disease events and promote collaboration and data sharing among wildlife professionals. It is a partner driven tool that provides a dynamic, timely, searchable web-based system for visualizing and accessing data on wildlife disease events...

Date published: March 13, 2018

DATA RELEASE - Laboratory experiment data—turbidity response to increasing silt and clay concentration-Data

These data were compiled during a laboratory experiment showing the turbidity response to increasing silt and clay concentration. The sediment used for the laboratory experiment was collected in the Grand Canyon study area, from the bank of the Little Colorado River, approximately 1 kilometer upstream from its confluence with the Colorado River.

Date published: March 7, 2018

Geospatial Data for Object-Based High-Resolution Classification of Conifers within Greater Sage-Grouse Habitat across Nevada and a Portion of Northeastern California

These products were developed to provide scientific and correspondingly spatially explicit information regarding the distribution and abundance of conifers (namely, singleleaf pinyon (Pinus monophylla), Utah juniper (Juniperus osteosperma), and western juniper (Juniperus occidentalis)) in Nevada and portions of northeastern California. 

Date published: March 7, 2018

West Nile virus susceptibility of American singer canaries: Data

Three datasets are included: 1) survival of domesticated canaries and American crows following sub-cutaneous challenges ranging from 101 – 105 plaque forming units of West Nile virus. 2) Arbitrary units of WNV detected by RT-PCR or plaque forming units of WNV cultured in vero cells in 4 separate studies. Culture results are indicated for each day post WNV challenge. 3) Weight (mass)...

Filter Total Items: 30,781
Publication Thumbnail
Year Published: 2019

Pathology in practice: Knemidocoptiasis in a pine grosbeak (Pinicola enucleator)

No abstract available.

Knowles, Susan; Swan, Jennifer L.; Roderick, Constance; Cole, Rebecca A.

Publication Thumbnail
Year Published: 2019

Virally-vectored vaccine candidates against white-nose syndrome induce anti-fungal immune response in little brown bats (Myotis lucifugus)

White-nose syndrome (WNS) caused by the fungus, Pseudogymnoascus destructans (Pd) has killed millions of North American hibernating bats. Currently, methods to prevent the disease are limited. We conducted two trials to assess potential WNS vaccine candidates in wild-caught Myotis lucifugus. In a pilot study, we immunized bats with...

Rocke, Tonie E.; Kingstad-Bakke, Brock; Wuthrich, Marcel; Stading, Ben; Abbott, Rachel C.; Isidoro Ayza, Marcos; Dobson, Hannah E.; dos Santos Dias, Lucas; Galles, Kevin; Lankton, Julia S.; Falendysz, Elizabeth; Lorch, Jeffrey M.; Fites, J. Scott; Lopera-Madrid, Jaime; Klein, Bruce; Osorio, Jorge E.; White, J. Paul

Publication Thumbnail
Year Published: 2019

Identification of single nucleotide polymorphisms for use in a genetic stock identification system for greater white-fronted goose (Anser albifrons) subspecies wintering in California

California provides wintering habitat for most greater white-fronted geese (Anser albifrons [GWFG]) in the Pacific Flyway and this population has rapidly increased since the 1980s. Increased harvest of GWFG wintering in California may prevent agricultural depredation while providing increased hunting opportunities. However, changes in harvest...

Wilson, Robert E.; Sonsthagen, Sarah A.; DaCosta, Jeffrey M.; Ely, Craig R.; Sorenson, Michael D.; Talbot, Sandra L.
Wilson, R.E., Sonsthagen, S.A., DaCosta, J.M., Ely, C.R., Sorenson, M.D., and Talbot, S.L., 2019, Identification of single nucleotide polymorphisms for use in a genetic stock identification system for greater white-fronted goose (Anser albifrons) subspecies wintering in California: U.S. Geological Survey Open-File Report 2019-1040, 18 p., https://doi.org/10.3133/ofr20191040.

Publication Thumbnail
Year Published: 2019

Global virtual water trade and the hydrological cycle: Patterns, drivers, and socio-environmental impacts

The increasing global demand for farmland products is placing unprecedented pressure on the global agricultural system and its water resources. Many regions of the world, that are affected by a chronic water scarcity relative to their population, strongly depend on the import of agricultural commodities and associated embodied (or virtual) water....

D'Odorico, Paolo; Carr, Joel A.; Dalin, Carole; Dell'Angelo, Jampel; Konar, Megan; Laio, Francesco; Ridolfi, Luca; Rosa, Lorenzo; Suweis, Samir; Tamea, Stefania; Tuninetti, Marta

Publication Thumbnail
Year Published: 2019

Reducing sampling uncertainty in aeolian research to improve change detection

Measurements of aeolian sediment transport support our understanding of mineral dust impacts on Earth and human systems and assessments of aeolian process sensitivities to global environmental change. However, sample design principles are often overlooked in aeolian research. Here, we use high‐density field measurements of sediment mass flux...

Webb, Nicholas P.; Chappell, Adrian; Edwards, Brandon L.; McCord, Sarah E.; Van Zee, Justin W.; Cooper, Bradley F.; Courtright, Ericha M.; Duniway, Michael C.; Sharratt, Brenton; Tedela, Negussie H; Toledo, David

Publication Thumbnail
Year Published: 2019

Cloud cover and delayed herbivory relative to timing of spring onset interact to dampen climate change impacts on net ecosystem exchange in a coastal Alaskan wetland

Rapid warming in northern ecosystems over the past four decades has resulted in earlier spring, increased precipitation, and altered timing of plant-animal interactions, such as herbivory. Advanced spring phenology can lead to longer growing seasons and increased carbon (C) uptake. Greater precipitation coincides with greater cloud cover possibly...

Leffler, Josh; Beard, Karen H.; Kelsey, Katharine C.; Choi, Ryan T.; Schmutz, Joel A.; Welker, Jeffrey

Publication Thumbnail
Year Published: 2019

Geomorphic change and biogeomorphic feedbacks in a dryland river: The Little Colorado River, Arizona, USA

The Little Colorado River in Arizona, U.S.A. has undergone substantial geomorphic change since the early 1900s. We analyzed hydrologic and geomorphic data at different spatial and temporal scales to determine the type, magnitude, and rate of geomorphic change that has occurred since the early 20th century. Since the 1920s, there have been 4...

Dean, David; Topping, David

Publication Thumbnail
Year Published: 2019

Modeling barrier island habitats using landscape position information

Barrier islands are dynamic environments because of their position along the marine–estuarine interface. Geomorphology influences habitat distribution on barrier islands by regulating exposure to harsh abiotic conditions. Researchers have identified linkages between habitat and landscape position, such as elevation and distance from shore, yet...

Enwright, Nicholas; Lei Wang; Wang, Hongqing; Osland, Michael; Feher, Laura; Borchert, Sinéad M.; Day, Richard

Publication Thumbnail
Year Published: 2019

Monitoring annual trends in abundance of eelgrass (Zostera marina) at Izembek National Wildlife Refuge, Alaska, 2018

A lagoon-wide, point-sampling survey of eelgrass (Zostera marina) abundance was conducted in Izembek Lagoon, Alaska, August 7–16, 2018, the ninth year of annual surveys (2007–11, 2015–18). Mean predicted aboveground biomass of eelgrass across 116 sampled points was 238 grams per square meter (g m-2) (95 percent confidence interval: 203–278 g m-2)...

Ward, David H.; Amundson, Courtney L.
Ward, D.H., and Amundson, C.L., 2019, Monitoring annual trends in abundance of eelgrass (Zostera marina) at Izembek National Wildlife Refuge, Alaska, 2018: U.S. Geological Survey Open-File Report 2019-1042, 8 p., https://doi.org/10.3133/ofr20191042.

Publication Thumbnail
Year Published: 2019

Drivers and impacts of water level fluctuations in the Mississippi River delta: Implications for delta restoration

This review synthesizes the knowledge regarding the environmental forces affecting water level variability in the coastal waters of the Mississippi River delta and relates these fluctuations to planned river diversions. Water level fluctuations vary significantly across temporal and spatial scales, and are subject to influences from river flow,...

Hiatt, Matthew R.; Snedden, Gregg; Day, John W.; Rohli, Robert V.; Nyman, John A.; Lane, Robert R.; Sharp, Leigh A.

Publication Thumbnail
Year Published: 2019

Efficacy of eDNA as an early detection indicator for Burmese pythons in the ARM Loxahatchee National Wildlife Refuge in the Greater Everglades Ecosystem

Environmental DNA (eDNA) detection of invasive species can be used to delimited occupied ranges and estimate probabilities to inform management decisions. Environmental DNA is shed into the environment through skin cells and bodily fluids and can be detected in water samples collected from lakes, rivers, and swamps. In south Florida, invasive...

Hunter, Margaret; Meigs-Friend, Gaia; Ferrante, Jason; Smith, Brian (Contractor); Hart, Kristen

Publication Thumbnail
Year Published: 2019

Conducting and interpreting fish telemetry studies: Considerations for researchers and resource managers

Telemetry is an increasingly common tool for studying the ecology of wild fish, with great potential to provide valuable information for management and conservation. For researchers to conduct a robust telemetry study, many essential considerations exist related to selecting the appropriate tag type, fish capture and tagging methods, tracking...

Brownscombe, Jacob W; Ledee, Elodie; Raby, Graham D.; Struthers, Daniel P; Gutowsky, Lee F G; Nguyen, Vivian M.; Young, Nathan; Stokesbury, Michael J W; Holbrook, Christopher; Brenden, Travis O.; Vandergoot, Christopher; Murchie, Karen J; Whoriskey, Kim; Mills-Flemming, Joanna; Kessel, Steven T.; Krueger, Charles C.; Cooke, Steven J.

Filter Total Items: 720
December 17, 2018

Burrowing Owl Regurgitating a Pellet

A burrowing owl regurgitates an owl pellet at the LAX Dunes Preserve caught by a wildlife camera.

Outstanding in the field podcast album art
December 10, 2018

Outstanding in the Field (Ep 1): To Bee or Not to Bee

The USGS Ecosystems Mission Area brings you Outstanding in the Field, a series of stories about our science, our adventures, and our efforts to better understand our fish and wildlife and the ecosystems that support them. This episode's buzz is all about pollinators, the birds, bees, bats, beetles, and other animals that feed on pollen from plants and help bring about one

December 8, 2018

Burrowing Owl at LAX Dunes Preserve

A burrowing owl, captured by a wildlife camera, standing next to the enterence of its den.

Manatee Health Assessment
December 6, 2018

Manatee Health Assessment

USGS conducts a health assessment on a mantee in Crystal River, Florida.

Four pits filled with water.
November 5, 2018

RestoreNet treatments

RestoreNet locations are testing commonly used restoration techniques, including pitting, mulching, and above-ground micro sites. Here, pits have filled with water, illustrating how this technique increases soil moisture by capturing rainwater. The project will illustrate which techniques work to establish plants depending on local conditions (like soil type) and climate

Wire crosses, called ConMods installed at a RestoreNet site.
November 5, 2018

RestoreNet treatments

RestoreNet locations are testing commonly used restoration techniques, including pitting, mulching, and above-ground micro sites. Here, metal crosses create an above-ground microsite that can increase soil moisture by providing shade and collecting debris under some conditions. The project will illustrate which techniques work to establish plants depending on local

Mulch treatment
November 5, 2018

RestoreNet treatments

RestoreNet locations are testing commonly used restoration techniques, including pitting, mulching, and above-ground micro sites. This photo shows the mulching treatment, which can increase soil moisture and lead to higher plant survival under some conditions. The project will illustrate which techniques work to establish plants depending on local conditions (like soil

A broken foundation where the Cape San Blas house stood
November 4, 2018

A broken slab is all that's left of Fish Inn after Hurricane Michael

A broken concrete foundation and some shattered floor tiles were all that remained of the sea turtle researchers' field station and home base after Category Four Hurricane Michael struck Cape San Blas on Oct. 10, 2018.

October 31, 2018

Drone Footage of Whiskeytown National Recreation Area after Carr Fire

Drone footage of Whiskeytown National Recreation area in Northern California in October 2018, captured by drone pilot and USGS WERC ecologist Chase Freeman.

USGS WERC is using drone imagery to understand how the 2018 Carr Fire affected ecosystems and cultural resources. The study, a collaboration with the National Park Service (NPS), focuses on Whiskeytown National

Pacific fisher on a tree looking into a bait box
October 24, 2018

Pacific fisher trying to grab a chicken dinner from the bait box

USGS scientists are documenting the distribution of three mid-sized mammalian carnivores – or mesocarnivores –in the Klamath Network Parks using remote cameras and hair snares. Little is known about the status of Pacific fishers, Pacific martens, and Sierra Nevada red foxes living in the Klamath Network, which include Crater Lake National Park, Lassen Volcanic National

graphic of N and S deposition and annual temp and precipitation from Horn, et al. (2018)
October 18, 2018

Figure 1, Horn, et al. (2018)

Gradients of N deposition, S deposition, mean annual temperature, and mean annual precipitation across the conterminous U.S. Panels are the a) mean total N deposition from 2000–2012, b) mean total S deposition from 2000–2012, c) mean annual temperature from 2000–2014, and d) mean annual precipitation form 2000–2014. Deposition data are from the TDEP product [23] and

A deeply eroded sand dune at Cape San Blas, Florida
October 16, 2018

Hurricane Michael cut deep into Panhandle dunes

A deeply eroded sand dune on the beach at Cape San Blas shows Hurricane Michael's impact on parts of the Florida Panhandle shoreline.

Filter Total Items: 289
Date published: April 25, 2018

Invasive Cuban Treefrogs Leap Out of Florida, Establish First Known Population in Louisiana

A population of exotic invasive Cuban treefrogs has been discovered in New Orleans, more than 430 miles (700 kilometers) from the nearest known population in Florida, making this the first known breeding population in the mainland United States outside that state, reports a new study by the U.S. Geological Survey. 

Scroll down to hear and download calls of Cuban treefrogs and two native treefrogs.

Date published: April 13, 2018

A Day in the Life of a WERC Seabird Scientist

In the featured photo, WERC scientists search for potential nesting habitat of seabirds like the Ashy Storm-Petrel (Oceanodroma homochroa) on False Klamath Rock off the coast of California.

Date published: April 11, 2018

NOROCK Scientist Receives USGS Award for Lifetime Achievement in Science Communications

Research Ecologist Dan Fagre is the recipient of the 2017 Eugene M. Shoemaker Award for Lifetime Achievement in Communications

Date published: March 29, 2018

New Control Methods Can Help Protect Coral Reefs from Invasive Species

Honolulu, Hawaii – Control efforts such as the removal of shipwrecks and application of chlorine may help mitigate the damaging effects of corallimorph, which is a type of invasive anemone, on valuable coral reefs in the Central Pacific Ocean, according to a new U.S. Geological Survey study.

Date published: March 19, 2018

New genetic test detects manatees' recent presence in fresh or saltwater

Environmental DNA picks up traces of the elusive mammals’ saliva, skin, waste, or exhaled breaths.


Date published: March 1, 2018

Waterbirds at Risk in the Chesapeake Bay

Scientists investigate the impacts of shoreline armoring

Date published: February 22, 2018

USGS and NASA Team Up to Help Scientists Study the “Social Networks” of Wildlife

In the future of wildlife tracking, sea otters have their own social network.

Date published: February 1, 2018

Polar Bears Film Their Own Sea Ice World

In June of 2014, the USGS released the first-ever polar bear point-of-view footage, offering a never-seen-before perspective from the top Arctic predator.

Date published: January 19, 2018

Scientists, volunteers rescue about 1,000 cold-stunned sea turtles

Florida's second-largest turtle rescue of 21st century is “exhausting, inspiring,” USGS biologist says

Date published: January 16, 2018

New Information on Bat Fungus Improves Detection of Deadly Disease

The fungus that causes white-nose syndrome, a deadly disease of hibernating bats, spreads rapidly by way of bats, then establishes and persists in soil and on walls of underground hibernation sites, according to a study published today.

Date published: December 13, 2017

Taking the Bait: Majority of Prairie Dogs Are Consuming Plague Vaccine

About 70 percent of wild prairie dogs successfully ingested baits containing an oral sylvatic plague vaccine, or SPV, that were distributed throughout their habitats, according to a new U.S. Geological Survey study.

Date published: December 12, 2017

Saving Salamanders: Vital to Ecosystem Health

Amphibians—the big-eyed, swimming-crawling-jumping-climbing group of water and land animals that includes frogs, toads, salamanders and worm-like caecilians—are the world’s most endangered vertebrates.