Megan Evansen

• Master of Science
• Senior Program Officer at World Wildlife Fund

The Endangered Species Act (ESA) provides legal protection to imperiled populations and their associated habitats. As a part of this process, listed species must undergo a general status review (also called 5‐Year Review) to assess the progress toward recovery every 5 years. However, almost all 5‐year reviews result in a status of “no change,” prom...

Currently 1677 species are listed under the U.S. Endangered Species Act (ESA), yet only a small percentage have been delisted due to recovery. In the fall of 2021, the U.S. Fish and Wildlife Service proposed delisting 23 species due to extinction. Tracking changes in species ‘recovery status over time is critical to understanding species’ statuses,...

The U.S. Endangered Species Act (ESA) is widely considered to be one of the strongest laws for protecting imperiled wildlife, with nearly all species protected under the law still existing today. Among the ESA's strongest provisions, at least as written, is the requirement under section 7(a)(1) that federal agencies use their authorities to help re...

The U.S. Endangered Species Act (ESA) is widely considered to be one of the strongest laws for protecting imperiled wildlife, with nearly all species protected under the law still existing today. Among the ESA’s strongest provisions, at least as written, is the requirement under section 7(a)(1) that federal agencies use their authorities to help re...

The U.S. Endangered Species Act (ESA) protects over 2,000 species, but no concise, standardized metrics exist for assessing changes in species recovery status. Tracking these changes is crucial to understanding species status, adjusting conservation strategies, and assessing the performance of the ESA. We helped develop and test novel metrics that...

Biodiversity is deteriorating at a global level as human actions like development, overexploitation, climate change, pollution, and other factors have led to a dramatic increase in the rate of extinction. The U.S. Endangered Species Act is considered one of the strongest laws in the world for protecting wildlife, but its effectiveness depends on pr...

The Supreme Court in Weyerhaeuser Co. v. United States Fish and Wildlife Service ruled that “critical habitat” under the Endangered Species Act (ESA) must first be “habitat,” but it did not attempt to define exactly what habitat is or how much deference the federal wildlife agencies should get on what is both a biological and policy question. The C...

Evaluating how wildlife conservation laws are implemented is critical for safeguarding biodiversity. Two agencies, the U.S. Fish and Wildlife Service and National Marine Fisheries Service (FWS and NMFS; Services collectively), are responsible for implementing the U.S. Endangered Species Act (ESA), which requires federal protection for threatened an...

As scientists, we call on the U.S. Congress to fully fund wildlife conservation programs to protect biodiversity from severe and growing threats. The effort to conserve threatened and endangered species must be prioritized to protect our national heritage and safeguard human well-being. In light of the unprecedented global biodiversity crisis ident...

Evaluating how wildlife conservation laws are implemented is critical to determining how best to protect biodiversity. Two agencies, the U.S. Fish and Wildlife Service and National Marine Fisheries Service (FWS and NMFS; Services collectively), are responsible for implementing the U.S. Endangered Species Act (ESA). This creates a "natural experimen...

In order to facilitate the routine NWP assimilation of operational advanced infrared sounder data (IASI on MetOp and CrIS on NPOESS) over high latitude land regions of the globe, we demonstrate a method for preparing the input to 1-D var data assimilation. The method involves the identification of clear sounder fields of view over snow/ice in winte...