Cooperative Agreement with a Partner of the Pacific Northwest Cooperative Ecosystem Studies Unit (CESU) | G21AS00293

Frequently Asked Questions (FAQs)

1) What is this grant opportunity about?

This is a US Geological Survey (USGS) cooperative agreement offered through the Northern Rocky Mountain Science Center (NOROCK). The project funds work to evaluate whether invasive American bullfrog eradication efforts in south-central Arizona produced the ecological outcomes managers intended, using environmental DNA (eDNA) and a rigorous Before-After-Control-Impact (BACI) study design.

2) What agency is offering the award?

The awarding agency is the Geological Survey (USGS), with the work offered through USGS and tied to NOROCK.

3) What type of award is this?

The opportunity is issued as a discretionary cooperative agreement.

4) What is the main purpose of the funded work?

The main purpose is to support analysis of eDNA filters collected in 2020 to 2021 from the same set of sites sampled in 2016. This enables a true before-versus-after evaluation of bullfrog eradication and helps measure how aquatic communities and amphibian disease risks responded after bullfrog removal.

5) Why is the project focused on American bullfrogs?

American bullfrogs are described as a major invasive threat across much of the western United States. They can prey on native amphibians and reptiles and may contribute to the spread or persistence of emerging wildlife diseases. This is especially important in the Southwest where native species face additional pressures from habitat change, drought, and disease.

6) What study design is being used, and why?

The project is framed around a Before-After-Control-Impact (BACI) design. BACI compares conditions before and after an intervention, and also compares impacted sites (where eradication occurred) to control sites (where it did not). This is presented as a common and rigorous way to measure change attributable to management actions rather than other environmental variation.

7) What is eDNA and how is it used in this project?

Environmental DNA (eDNA) is used as the main monitoring tool. In this project, eDNA sampling is used to characterize aquatic species presence and pathogen presence across a network of sites. The funding specifically supports analyzing eDNA filters collected later (2020 to 2021) to compare against earlier (2016) baseline conditions.

8) What is being evaluated besides bullfrog presence?

In addition to assessing whether bullfrogs were removed or reduced, the project evaluates responses of native aquatic species and amphibian pathogens, with specific emphasis on amphibian chytrid fungus (Bd) and ranaviruses (RV).

9) What earlier work does this build on?

The opportunity builds on a landscape-scale bullfrog eradication campaign funded in 2016 under the US Fish and Wildlife Service (USFWS) Cooperative Recovery Initiative (CRI). USGS collected pre-eradication eDNA samples in 2016 just before eradication actions were carried out.

10) How many sites were sampled in the baseline (2016) effort?

The 2016 pre-eradication sampling described included 21 sites slated for eradication work and 17 control sites. The control sites were split between locations where bullfrogs were present (8 sites) and absent (9 sites).

11) How many total sites are included in the overall study network?

The opportunity describes 39 total sites in the overall set of sites originally sampled in 2016, and the later 2020 to 2021 eDNA filters come from the same overall set of sites.

12) What did the 2016 eDNA results suggest about bullfrogs and Chiricahua leopard frogs?

The pre-eradication samples suggested a strong negative association between bullfrogs and the Chiricahua leopard frog. In practical terms, sites with bullfrogs were described as being very unlikely to contain Chiricahua leopard frogs.

13) What did the 2016 eDNA results suggest about disease risk at bullfrog sites?

The same pre-eradication samples indicated that sites with bullfrogs were more likely to show evidence of amphibian chytrid fungus (Bd) and ranaviruses (RV), both identified as serious pathogens for amphibians and threats to Chiricahua leopard frogs.

14) Why analyze the 2020 to 2021 samples instead of relying on short-term observations?

The later samples allow a true before-versus-after comparison across the study network and help confirm whether bullfrog eradication was successful and sustained over time, rather than relying only on short-term observations. They also allow clearer measurement of changes in native species and pathogens after bullfrog removal.

15) Are there any indications of positive ecological responses already?

Managers have observed Chiricahua leopard frogs quickly recolonizing some sites where bullfrogs were eradicated. The opportunity positions eDNA-based analysis as a way to provide broader, more systematic evidence across the entire network.

16) What management-relevant outcomes is the project expected to document?

The project is aimed at producing defensible evidence about invasive bullfrog eradication outcomes, including (1) confirming whether bullfrogs were truly removed or reduced across eradication sites and (2) documenting whether native imperiled herpetofauna and key amphibian pathogens (notably Bd and ranavirus) changed in ways consistent with improved conditions for sensitive native species like the Chiricahua leopard frog.

17) What administrative program is this opportunity tied to?

The award is issued under the Cooperative Ecosystem Studies Unit (CESU) Program and is specifically tied to the Pacific Northwest CESU.

18) Who is eligible to apply?

Eligibility is limited to applicants who are active partners in the Pacific Northwest CESU.

19) What kinds of organizations are generally involved in CESUs (as described here)?

CESUs are described as partnership networks that connect federal agencies with universities, nonprofits, and other research organizations to deliver research, technical assistance, and education.

20) What is the funding area or activity category for this opportunity?

The funding activity falls under science and technology and other research and development.

21) What is the CFDA number listed for the opportunity?

The CFDA number provided is 15.808.

22) What is the opportunity number?

The opportunity number is G21AS00293.

23) When was the opportunity posted and when did it close?

The posting date was February 2, 2021, and the original closing date was February 19, 2021.

24) What is the maximum award amount?

The maximum award amount listed is $28,200.

25) How many awards are expected?

The opportunity indicates an expected award count field, but the provided text does not clearly specify a number.

26) What geographic area does the ecological evaluation focus on?

The project focuses on south-central Arizona, where the bullfrog eradication efforts being evaluated took place.

27) Which species and disease agents are specifically highlighted?

The opportunity specifically highlights the invasive American bullfrog, the native Chiricahua leopard frog, and two amphibian pathogens: amphibian chytrid fungus (Bd) and ranaviruses (RV).

28) What is the main value of using eDNA in this context (as described in the opportunity)?

The opportunity emphasizes that eDNA can provide broader, more systematic evidence across the entire study network and can capture information about pathogens that might not be obvious from visual surveys alone.