FY 2017 Biological Program Activities Report
Each year the US Fish and Wildlife Service issues an annual report on the biological program activities on the Sheldon-Hart Mountain refuges. The report, which should be of interest to all the Friends of Hart Mountain, describes the monitoring and assessment activities conducted by FWS and such partners as Oregon State Department of Fish and Wildlife (ODFW), the BLM, University of Nevada-Reno, others. The report for Fiscal Year 2017 several categories, including Birds, Mammals, and Habitat and Climate.
Of the birds discussed, the Greater sage-grouse is of greatest interest. Annual ground surveys are conducted each spring on a small set of “leks” to monitor general population trends. In 2017, 44.3 males per lek were observed, compared with 44.5 in 2016 and a long-term (1980-2016) average of 45.0 males. Additionally, in cooperation with USGS, riparian songbird monitoring is being conducted on Hart and Sheldon to investigate changes in riparian vegetation and songbird populations following following removal of cattle in the mid-1990s.
Among the mammals monitored the most sensitive is the California Bighorn sheep. Results of a July 2017 survey yielded a minimum population estimated of 149 animals with 34.2 rams per 100 ewes. This marked a decline from 2016 (168 sheep observed). The 20-year average trend is -0.4%. In November, Mule Deer were also surveyed. Ninety-eight deer were observed in 23 groups, with averages of 19.3 bucks and 49.1 fawns per 100 does. These figures may be compared with long-term ratios (1967-2016) of 31.6 bucks and 59.3 fawns per 100 does. Other studies covered the Pygmy Rabbit and Bat inventory and monitoring. Population dynamics of Pygmy Rabbit colonies and their distribution through out the Sheldon-Hart Refuge Complex and the surrounding areas are being assessed in collaboration with several partners.
Probably of keenest interest to Friends of Hart Mountain are the Pronghorn surveys. In July 2017 helicopter surveys of pronghorn habitat were conducted on both Hart and Sheldon refuges. Additionally, with the cooperation of ODFW, a concurrent survey of pronghorn in the areas between the two refuges was completed. The total for both refuges and the area between them was 7,030 animals. Of the 2,691 on Hart Mountain, there were 39.1 bucks and 35.7 fawns per 100 does; the average population trend is +9.0%
The report also contained brief mention of the Feral Horse and Burro population, which has a negative impact on the forage and water sources for wildlife. Since 2015 both refuges have been determined to be “essentially feral horse and burro-free.”
Central to the survival of all the species found on Hart Mountain are Habitat and Climate. The report noted the July 2017 fire caused by a military flare that burned about 480 acres. The burn was treated to control invasive grasses in Fall 2017, and in late May shrubs were planted by Friends volunteers in the affected portions of the Willow Creek riparian zone. Aside from such restoration work, five of the six riparian monitoring sites established in 2015 were surveyed. The sites will be used to establish a baseline for comparison of the health of riparian habitats under differing management strategies throughout Washington, Oregon, Nevada, Idaho and Montana. Additionally, beginning in 2015 the Oregon DEQ began annual sampling in Guano Creek as part of a reference trend monitoring network throughout the state.
In 2013 Refuge staff began inventorying and assessing the health of Aspen stands in Sheldon-Hart Complex. As of 2018, 820 acres had been mapped and surveyed, with analyses to come. The Complex is continuing efforts to improve the resilience and resistance of sage-steppe habitats to juniper encroachment, focusing on open sage-grouse nesting and brood rearing areas. Encroaching juniper was removed from over 5,000 acres of sage steppe, and hand reseeding was undertaken using a customized mix of native grass and forb seed. Field crews continued rapid assessment surveys of new areas.
Members of the Friends of Hart Mountain have participated in many of the monitoring and restoration activities. If you are interesting in contributing to these efforts, keep an eye on the Friends Newsletter and website for announcement of future opportunities.
Source: Summary of FY 2017 Biological Program Activities: Sheldon-Hart Mountain Wildlife Refuge Complex. December 2017.
Of the birds discussed, the Greater sage-grouse is of greatest interest. Annual ground surveys are conducted each spring on a small set of “leks” to monitor general population trends. In 2017, 44.3 males per lek were observed, compared with 44.5 in 2016 and a long-term (1980-2016) average of 45.0 males. Additionally, in cooperation with USGS, riparian songbird monitoring is being conducted on Hart and Sheldon to investigate changes in riparian vegetation and songbird populations following following removal of cattle in the mid-1990s.
Among the mammals monitored the most sensitive is the California Bighorn sheep. Results of a July 2017 survey yielded a minimum population estimated of 149 animals with 34.2 rams per 100 ewes. This marked a decline from 2016 (168 sheep observed). The 20-year average trend is -0.4%. In November, Mule Deer were also surveyed. Ninety-eight deer were observed in 23 groups, with averages of 19.3 bucks and 49.1 fawns per 100 does. These figures may be compared with long-term ratios (1967-2016) of 31.6 bucks and 59.3 fawns per 100 does. Other studies covered the Pygmy Rabbit and Bat inventory and monitoring. Population dynamics of Pygmy Rabbit colonies and their distribution through out the Sheldon-Hart Refuge Complex and the surrounding areas are being assessed in collaboration with several partners.
Probably of keenest interest to Friends of Hart Mountain are the Pronghorn surveys. In July 2017 helicopter surveys of pronghorn habitat were conducted on both Hart and Sheldon refuges. Additionally, with the cooperation of ODFW, a concurrent survey of pronghorn in the areas between the two refuges was completed. The total for both refuges and the area between them was 7,030 animals. Of the 2,691 on Hart Mountain, there were 39.1 bucks and 35.7 fawns per 100 does; the average population trend is +9.0%
The report also contained brief mention of the Feral Horse and Burro population, which has a negative impact on the forage and water sources for wildlife. Since 2015 both refuges have been determined to be “essentially feral horse and burro-free.”
Central to the survival of all the species found on Hart Mountain are Habitat and Climate. The report noted the July 2017 fire caused by a military flare that burned about 480 acres. The burn was treated to control invasive grasses in Fall 2017, and in late May shrubs were planted by Friends volunteers in the affected portions of the Willow Creek riparian zone. Aside from such restoration work, five of the six riparian monitoring sites established in 2015 were surveyed. The sites will be used to establish a baseline for comparison of the health of riparian habitats under differing management strategies throughout Washington, Oregon, Nevada, Idaho and Montana. Additionally, beginning in 2015 the Oregon DEQ began annual sampling in Guano Creek as part of a reference trend monitoring network throughout the state.
In 2013 Refuge staff began inventorying and assessing the health of Aspen stands in Sheldon-Hart Complex. As of 2018, 820 acres had been mapped and surveyed, with analyses to come. The Complex is continuing efforts to improve the resilience and resistance of sage-steppe habitats to juniper encroachment, focusing on open sage-grouse nesting and brood rearing areas. Encroaching juniper was removed from over 5,000 acres of sage steppe, and hand reseeding was undertaken using a customized mix of native grass and forb seed. Field crews continued rapid assessment surveys of new areas.
Members of the Friends of Hart Mountain have participated in many of the monitoring and restoration activities. If you are interesting in contributing to these efforts, keep an eye on the Friends Newsletter and website for announcement of future opportunities.
Source: Summary of FY 2017 Biological Program Activities: Sheldon-Hart Mountain Wildlife Refuge Complex. December 2017.