Distribution of Mountain Plovers in the Powder River · PDF fileDistribution of Mountain...

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  • Distribution of Mountain Plovers in the Powder River Basin, Wyoming

    Solicitation No. KAQ001005

    Final - February 22, 2002

    Prepared For:

    Bureau of Land Management 5353 Yellowstone Road

    P.O. Box 1828Cheyenne, Wyoming 82003-1828

    Prepared By:

    Rhett E. Good, David P. Young Jr., and Jamie P. EddyWestern EcoSystems Technology, Inc

    2003 Central AvenueCheyenne, Wyoming 82001

  • Powder River Basin Mountain Plover Surveys Western EcoSystems Technology, Inc.



    The mountain plover (Charadrius montanus) is currently proposed for listing as threatened underthe Endangered Species Act by the U.S. Fish and Wildlife Service. In order to better understandthe current distribution of mountain plovers in the Powder River Basin, the Bureau of LandManagement (BLM) contracted Western EcoSystems Technology, Inc (WEST) to conductmountain plover presence/absence surveys in the Powder River Basin (Figure 1). The area of thesurvey has a large potential for coal bed methane production, which could potentially degradehabitat suitability for mountain plovers.

    Mountain plovers arrive on their breeding grounds, including those in Wyoming, in late Marchto late April. The nesting season generally occurs from May to July with young birds fledging inJuly and August (Knopf 1996). After courtship, the male will make several nest scrapes fromwhich one is selected. The female will typically lay three eggs, however, clutch size can varyfrom one to four. During years of high insect numbers, females can lay one clutch for the maleand then a subsequent clutch for herself. Usually one egg is laid a day and incubation does notbegin until the clutch is complete to insure synchronous hatching. Eggs are incubated for 28-31days. After hatching the adults lead the precocial young away from the nest within a few hours. Post hatching movement varies with age of chicks but generally increases with age. Broodstypically remain near the nest location for one day and then begin increasing distances moved. Studies in the Pawnee National Grassland in Colorado, found that broods may move up to 1600m (.1 mile) from the nest (Knopf 1992, 1996) and generally move 100-500 m per day (Knopfand Rupert 1996). Fledging occurs around 36 days post hatching (Miller and Knopf 1993).

    Mountain plovers begin congregating in flocks in late July and typically begin migration awayfrom the breeding ground by August (Knopf and Rupert 1996, Knopf 1996). Mountain ploversare opportunistic feeders whose diet consists almost exclusively of invertebrates (Knopf 1998). In Colorado, mountain plovers eat mostly grasshoppers, crickets, beetles, and ants (Baldwin1971).

    The preferred habitat of mountain plover is shortgrass prairie and grassland but they may beobserved in other habitats during migration (Bent 1962, Davis and Knight 1989). Typicalmountain plover habitat is arid, shortgrass plains with level to gently rolling topography. Vegetation is generally less than 10 cm (4 in) in height and often consists of blue grama(Bouteloua gracilis), buffalograss (Buchloe dactyloides), bluebunch wheatgrass (Agropyronspicatum), low growing sagebrush (Artemesia spp), and other low forbs (Parrish 1988, Knopf1996). Olson-Edge and Edge (1987) noted a strong association of mountain plovers and prairiedog towns. They also noted that irregular topography and tall vegetation precluded use by thisspecies. Knopf and Miller (1994) suggest bare ground is an important factor for good breedinghabitat. Mountain plover use is often associated with prairie dog towns, heavily grazed orburned areas. They will also use areas in and around alkali flats and claypans (Knopf 1996) andplowed agricultural fields (Shackford and Leslie 1995, Young and Good 2000).

  • Powder River Basin Mountain Plover Surveys Western EcoSystems Technology, Inc.


    Figure 1. A map of the Powder River Basin survey area.

  • Powder River Basin Mountain Plover Surveys Western EcoSystems Technology, Inc.


    Mountain plovers historically bred from northern New Mexico north to southern Alberta,Canada, and from northeast Utah east to eastern Montana, western South Dakota, westernNebraska, western Kansas, and northern Texas. Historic winter range included mainlyCalifornia and Texas, with some birds wintering in Arizona, New Mexico, and Mexico. Todaymountain plovers are usually found east of the Continental Divide in Colorado, Wyoming, andMontana (USFWS 1999). Mountain plover distribution within the Powder River Basin is notwell known.

    The Powder River Basin ia an intermontane basin located in northeastern Wyoming andsoutheastern Montana. The basin is approximately 250 mi x 100 mi (Dolton and Fox 1995). The Powder River Basin contained several mires between river channels and lake marginsduring the Paleocene era. These mires formed large deposits of coal, some greater than 60 m inthickness (USGS 2001). The methane gas associated with coal beds has been much sought afterwithin recent years. Approximately 3,500 coal bed methane wells have been completed withinthe Powder River Basin since 1998 (Flores et al. 2001).


    Tape play back surveys were conducted for mountain plovers in the Powder River Basin EISarea from April 26 - May 25, 2001. The survey area was split with the Wyoming NaturalDiversity Database (WYNDD). Our surveys focused on the western half of the survey area inJohnson, Sheridan and Converse Counties, specifically areas contained within the Sheridan,Buffalo and Kaycee BLM maps (Figure 2). We also surveyed for mountain plovers south ofNewcastle. This report only includes data collected by WEST, Inc.

    Tape Play Back Surveys. Mountain plover courtship songs recorded on the Pawnee NationalGrassland in Colorado were used during surveys. Tapes were played for 1 - 2 minutes, andmountain plover auditory responses were listened for. The surrounding area was also scannedwith binoculars during surveys. Mountain plover courtship songs were broadcast using walkmantape players amplified through Radio Shack Powerhorns (Model # 322027). The total cost forone broadcast unit was approximately $50.

    Two crews (one person per crew) were used to survey for mountain plovers. Tape play backsurveys were conducted in areas of low to high potential habitat every 0.5 mile along surveyroutes. Routes were initially located based upon Gap Analysis Program (GAP) vegetation layersand BLM and Wyoming Game and Fish Department prairie dog coverages. Additional surveyroutes were selected based upon field observations and requests by district BLM biologists.

  • Powder River Basin Mountain Plover Surveys Western EcoSystems Technology, Inc.


    Figure 2. A map of Wyoming showing the location of transects used to survey for mountainplovers by WEST, Inc. in 2001.

    GPS and GIS. The position (UTM NAD 27, Zone 13) of every survey point and observationsof BLM sensitive species between survey points were recorded with handheld TrimbleGeoexplorer Global Position System (GPS) units. Survey routes were digitized using ArcView. Survey points and observations of BLM sensitive species were loaded in to a shapefile and weredelivered to Jeff Carroll, BLM, in October 2001.

    Habitat Potential. Habitat along survey routes were rated as low, medium, high or no potentialfor mountain plover occurrence. Habitat ratings were developed by WEST personnel basedupon published literature and extensive field observations (Appendix A).

    Areas along survey routes with no potential for mountain plover occurrence (rocky canyons,forests, tall shrubs, rugged topography and residential areas) were not surveyed. Areas with high

  • Powder River Basin Mountain Plover Surveys Western EcoSystems Technology, Inc.


    potential were often surveyed at intervals closer than 0.5 mi to confirm the presence or absenceof mountain plovers.

    Nest Searches. Nest searches were conducted within areas where mountain plovers weredetected and public lands were present. Nest searches were conducted by driving paralleltransects (approximately 50 m apart) and looking for birds flushed from nests. If a mountainplover was detected, the observer moved at least 50 m from the bird and observed the plover todetermine if it returned to a nest. Birds were observed for a maximum of 15 minutes tominimize the potential for disturbing nesting birds.


    Survey Effort. Mountain plovers were surveyed for at 896 points over 696.90 miles on 37transects (not including revisits). Areas of high mountain plover potential where plovers werenot detected initially were surveyed again at 49 points on transects Irrigary Road, Buffalo-Sussexcutoff and Nine Mile Road (see attached map South of Buffalo, Wyoming). The large prairiedog town on TTT road (see attached map North of Kaycee, Wyoming) was surveyed severaltimes for mountain plovers on our way to other routes (not included in re-visit total).

    Habitat Potential. The habitat potential for mountain plover occurrence was assessed at 896survey points (Table 1). A total of 130 (14 %) survey points were considered high potentialhabitat, 338 (38 %) were medium potential habitat and 428 (48 %) low potential habitat. Highpotential habitat typically was flat, grazed short-grass prairie with cacti. High potential habitatoften included prairie dog towns. Medium potential habitat was characterized by the presence offavorable vegetation (short-grass or low shrubs) or prairie dog towns, but lacking flattopography, or vice versa. Medium potential habitat sometimes included short vegetation orprairie dog towns and flat topography, but lacked large amounts of bare ground. Low potentialhabitat often included areas with steeply sloping topography or rolling sage