A04_-_SOW_SWFL_Monitoring_fw94_1.docx

1. PROJECT TITLE: Landscape-scale Assessment of Breeding Flycatcher Populations in Clark and Lincoln Counties

2. FWS PROJECT OFFICERS:

Rabecca Lausch, Acting Wildlife Refuge Manager USFWS, Desert National Wildlife Refuge Complex 702-540-5278, rabecca_lausch@fws.gov

3. OVERVIEW:

This survey and monitoring project is part of a larger project administered by the U.S. Fish and Wildlife Service (Service) establishing a landscape-scale migration monitoring network in Southern Nevada through the Southern Nevada Public Lands Management Act.

The Service will

1. Actively collaborate with RECIPIENT to determine monitoring areas, methods, and priorities.

2. Review reports and provide feedback

3. Communicate with RECIPIENT on a regular basis.

RECIPIENT will

1. Provide all human resources functions associated with field personnel to accomplish survey and monitoring goals determined by the Service,

2. Compile and analyze data

3. Draft reports.

4. PROBLEM STATEMENT AND IMPLICATIONS:

The Southwestern Willow Flycatcher (SWFL, Empidonax trailii extimus) is an endangered subspecies of Willow Flycatcher found in small numbers in riparian habitats in California, Arizona, and Nevada. Pahranagat NWR is located at the northern edge of the range of the Southwestern Willow Flycatcher and houses a natural breeding population in a mature willow forest adjacent to the refuge’s Upper Lake. This breeding population has been the most successful in the region for many years and has been studied to varying degrees. Monitoring is a key component of the National Wildlife Refuge System, and an essential step in maintaining our knowledge of endangered species status as our world continues to change. Through this agreement, we will expand the monitoring efforts of Southwestern Willow Flycatcher in Clark and Lincoln counties which are within the range of this species. This expansion will help land managers assess the importance of each breeding location to the landscape-level population, identify key areas to focus habitat restoration efforts, maximize impact of limited resources, and support endangered species recovery efforts in the region.

5. OBJECTIVES and METHODS:

USFWS would like to conduct a landscape-scale assessment of breeding flycatcher populations in Clark and Lincoln Counties. Work will be conducted at the Meadow Valley Wash, Key Pittman, Pahranagat, Warm Springs, and Overton study areas. Each study area is comprised of between one and 17 study sites. Flycatcher surveys will be conducted at Meadow Valley Wash, Key Pittman, Pahranagat, and Overton. SNWA conducts flycatcher surveys annually at Warm Springs; therefore, no surveys will be conducted at Warm Springs under this proposal. Flycatcher monitoring will be conducted at Meadow Valley Wash, Key Pittman, Pahranagat, and Warm Springs. No flycatchers were detected at Overton during flycatcher surveys in 2024; therefore, no territorial flycatchers are expected in 2026 and RECIPIENT can expect to conduct only flycatcher surveys at Overton. Flycatcher surveys will also be completed at additional areas identified as possible flycatcher breeding sites in Clark County and/or Lincoln County, NV.

Task 1. Flycatcher Surveys RECIPIENT will complete protocol-level surveys at all study areas except Warm Springs following methods outlined in Sogge et al. (2010). The USFWS Southwestern Willow Flycatcher Protocol (USFWS 2000) recommends five broadcast surveys at each site, with one survey between May 15 and 31, two surveys between June 1 and 24, and two surveys between June 25 and July 17. Each round of survey will be spaced at least 5 days apart. Surveys will be conducted between 30 minutes before sunrise and 10:30 a.m. Survey points will be located within the habitat when possible and spaced approximately 30 meters (m) (98 feet) apart. At each survey point, observers will play the broadcast call sequence consisting of a 10-second pre-broadcast listening period and approximately 15 seconds of fitz-bew (primary song) and breet calls followed by a 1‑minute listening period. Playback of conspecific vocalizations may be used to elicit fitz-bew responses from birds that are believed to be willow flycatchers by behavior or morphology but have not produced a diagnostic vocalization.

When a flycatcher is detected, the observer will remain in the territory for up to 30 minutes. During this period, the observer will attempt to locate the bird visually and note its general behavior, focusing on documenting evidence of territorial or breeding behavior (e.g., extended, unsolicited song; presence of an unchallenged flycatcher; soft whitt calls between two flycatchers; or a flycatcher carrying nesting material or food). The observer will also attempt to determine whether the bird has leg bands and will record the band combination if the bird is banded. The observer will record the GPS coordinates of each willow flycatcher detected, or, if the location of the bird is not accessible, the location of the observer along with the distance and direction to the responding bird will be recorded. If territorial or breeding behaviors are observed, the observer will follow the territory and nest monitoring protocol described below. If the bird does not display any territorial or breeding behaviors, the observer will resume surveying at least 50 m (164 feet) beyond the bird’s location to minimize the likelihood of the bird following the broadcast. Surveys will not be conducted within 50 m (164 feet) of any known occupied flycatcher territory center or nest location.

Task 2. Flycatcher Monitoring and Banding Territory and nest monitoring involves frequent visits to all flycatcher territories and results in locating flycatcher nests, determining nest fates, and calculating flycatcher nest success and productivity.

Territory and Nest Monitoring RECIPIENT will complete flycatcher territory and nest monitoring during 13 weekly visits to each territory between May 15 and August 15. Nest searching and nest monitoring, following methods described by Martin et al. (1997), Martin and Geupel (1993), Ralph et al. (1993), and Rourke et al. (1999), will commence once a territorial flycatcher has been detected. Each territory will be visited approximately once every 7 days to find and monitor nests. RECIPIENT will conduct one monitoring visit per week at Meadow Valley Wash and Warm Springs. Due to large numbers of territories anticipated at Key Pittman and Pahranagat, RECIPIENT may conduct monitoring on two days each week at those study areas to monitor every known territory and/or nest.

Flycatcher monitoring will begin as early as 30 minutes before sunrise. A USFWS-permitted biologist will approach known territories or nests and listen for flycatcher vocalizations while observing for movement. Flycatchers will be identified by the fitz-bew vocalization. Observers will also listen for wheeo, breet, brrr/kitter, and interaction calls, which can be useful in identifying flycatchers. Nests will generally be monitored using a mirror on a telescoping pole, when possible, to determine nest contents (i.e., number of eggs or nestlings), including the presence of any brown-headed cowbird (Molothrus ater) (cowbird) eggs. No active nest will be mirror poled until it is estimated to be in the incubation stage to minimize disturbance and the potential for nest abandonment. Nests that are too high to be monitored with a mirror pole will be observed with binoculars, and adult behavior, along with observation of any young in the nest, will be used to determine nest stage and nestling age, when possible. Other than during nestling banding, no nest will be mirror poled or approached closely after young are 8 days of age to avoid forced fledging. Nests will not be mirror poled or otherwise approached closely when cowbirds or other potential nest predators are detected in the vicinity. The nest status at each territory will inform the timing of subsequent visits. These visits will be timed, when possible, to best assess fledge/fail status for the greatest number of nests and confirm the number of fledglings for each nest.

Nesting attempts will be determined to be successful if fledged young are observed in the immediate vicinity of the nest or are observed being fed by banded adults known to be associated with that nest. Similarly, the number of fledglings each nest produces will be determined by the number of fledglings visually confirmed, and not the number of nestlings known to have been in the nest. All failed nests will be inspected to determine the condition of the nest and to record the presence of eggs, eggshells, or dead nestlings in or around the nest.

Cowbird Egg Addling/Replacement and Nestling Removal Cowbird brood parasitism of flycatcher nests has been variable at southern Nevada study areas. If an accessible flycatcher nest is parasitized on or before the fifth day of incubation, the cowbird egg will be addled via vigorous shaking or replaced with an artificial cowbird egg. Cowbird eggs will not be removed from the nest without replacement so as not to mimic a partial depredation event, which could cause nest desertion. Shaking cowbird eggs greatly reduces the chance of the egg hatching, and there is no evidence that this activity results in nest desertion (McLeod and Pellegrini 2013; McLeod, Pellegrini, et al. 2019). If a cowbird nestling is present in an accessible flycatcher nest, the cowbird nestling will be removed and euthanized.

Banding Flycatcher adults and nestlings will be color banded as time permits. Color banding improves the certainty with which individual flycatchers are associated with a specific territory or nest. Resighting of color band combinations will occur during territory and nest monitoring visits. Adult flycatchers will be captured with mist nets, which provide the most effective technique for live capture of adult songbirds (Ralph et al. 1993). A targeted capture technique (in accordance with Sogge et al. 2001) will be used, whereby a variety of conspecific vocalizations will be broadcast from remote speakers to lure territorial flycatchers into the nets. Each adult flycatcher will be banded with a single, numbered U.S. federal aluminum band on one leg and a colored metal pin-stripe band on the other leg.

Morphological measurements will be recorded for each captured adult willow flycatcher, including culmen, tail, wing, fat level, and molt. Sex will be determined based on the presence of a cloacal protuberance in males or brood patch and/or egg(s) in the oviduct of females. Captured flycatchers lacking breeding characteristics and not observed engaging in male advertising song will be sexed as unknown. Flycatchers with retained primary, secondary, and/or primary covert feathers (multiple aged remiges) will be aged as second year adults, and those without (uniformly aged remiges) will be aged as after hatch year (in accordance with Kenwood and Paxton 2001 and Koronkiewicz et al. 2002).

Nestlings will be banded at 7 to 10 days old when they are large enough to retain leg bands, yet young enough that they will not prematurely fledge from the nest (Paxton et al. 1997; Whitfield 1990). Nestlings will be banded only when the location of the nest is such that nest access and removal/replacement of the nestlings will not endanger the nest, nest plant, or nestlings. Nestlings will also be banded with a single, numbered U.S. federal aluminum band on one leg and a colored metal pin-stripe band on the other leg. Resighting of fledgling flycatchers aids in confirming the number of fledglings produced from each nest and will allow for a more accurate determination of nest success and productivity.

Task 3. Data Analysis and Annual Report RECIPIENT will submit an electronic draft report to USFWS by December 15 each year, detailing the results of flycatcher surveys, monitoring, and banding at each study area. The report will include the number of flycatcher territories, pairs, and nests; the number of cowbird eggs addled or replaced; the number of cowbird nestlings removed; and the fate of all flycatcher nests, including parasitism status. Percent nest success, fecundity, and causes of nest failure will be reported for each study area. Parasitism rates and flycatcher productivity metrics observed each year will be compared with those observed at the same study areas in earlier years. RECIPIENT will submit a final copy of the report to USFWS no more than 1 month after receipt of a consolidated set of comments associated with review of the draft report.

6. PERIOD OF PERFORMANCE: April 1, 2026 – August 31, 2030.

7. PRODUCTS AND SCHEDULE:

YEAR 1

*If incremental funding is available and mutually agreed upon by both partners, additional years of monitoring will be conducted under this agreement.

YEAR 2*

YEAR 3*

YEAR 4*

YEAR 5*

8. INCREMENTAL FUNDING STATEMENT

Additional funding can be added to this agreement via agreement modifications to support supplemental activities including but not limited to transmitter attachment activities or additional monitoring locations or time periods.

9. COMPLIANCE

As a condition of award, the Recipient and their sub-recipient(s) and contractor(s) must not begin any potentially impactful work related to this award until the Service has notified you in writing that such work can begin. Recipients and sub-recipients of Federal grants and cooperative agreement awards must comply with the requirements of the National Environmental Policy Act (NEPA), Section 7 of Endangered Species Act (ESA), and Section 106 of the National Historic Preservation Act (NHPA).