NEOTROPICAL MIGRATORY BIRDS

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1 NEOTROPICAL MIGRATORY BIRDS Introduction Neotropical migratory birds regularly summer in North America and winter south of the Tropic of Cancer. Population declines in many of these species appear to be due to loss, modification, and fragmentation of breeding habitat; loss of wintering and migratory habitat; and brood parasitism (Montana Partners in Flight 2000). Information Sources The effects on neotropical migrants are discussed by using analysis presented in the Forest Vegetation sections of this chapter; and in the riparian analysis (Hydrology section of the project file). The USFS Northern Region Songbird Monitoring Program (Hutto 1995a, Hutto and Young 1999, Hutto and Young 2002, Young and Hutto 2002) provides data on population trends, habitat relationships, and effects from past management activities for neotropical migratory birds breeding in western Montana. These have been combined to determine population trends on a continental, regional, statewide, or physiographic region scale. Wildlife population viability concerns on the Flathead National Forest, and larger scales, are assessed in the document, Flathead National Forest Evaluation and Compliance With NFMA Requirements to Provide for Diverse Animal Communities (June, 2009; project file). Analysis Area The evaluation of direct, indirect, and cumulative effects on neotropical migratory birds was done at the same spatial and temporal extent as that for and riparian habitats and old growth habitats. All habitat attributes are distributed across this area. It is also representative of effects of fires, natural tree mortality, timber harvest, fuel reduction, firewood cutting, and other factors across the landscape. It is large enough to include the spring, summer, and fall range of numerous individuals of these migratory bird species as well as the home range of numerous wildlife species using riparian habitats. It is sufficient to evaluate the ability of the habitat to support populations of wildlife and plant species using riparian habitats. Affected Environment/Existing Condition The United States portion of the Northern Rockies Bird Conservation Region has 22 species listed as Birds of Conservation Concern (USFWS 2008), Table These species are migratory and non-migratory birds not designated as federally threatened or endangered but represent the highest conservation priorities. Three of these are sensitive wildlife species on the Flathead National Forest; two are listed as old-growth associates

2 Table Birds of Conservation Concern in the Flathead Basin Species * Status and Habitat Association ** Relative Abundance in the Flathead Basin and Neighboring Areas Bald Eagle B; Sens; R Common Black Rosy-Finch b Rare Black Swift B; R Rare Brewer s Sparrow b Uncommon Calliope Hummingbird B Common Cassin's Finch b Uncommon Ferruginous Hawk t Rare Flammulated Owl B; Sens; OG Occasional Lewis s Woodpecker B; OG Occasional Loggerhead Shrike t Occasional Long-billed Curlew B; R Uncommon Olive-sided Flycatcher B Uncommon Peregrine Falcon B; Sens; R Rare Sage Thrasher t Rare Swainson's Hawk t Occasional Upland Sandpiper t Rare White-headed t Rare Woodpecker Williamson s Sapsucker B Uncommon Willow Flycatcher B; R Uncommon * Species not in table because no record in the Flathead Basin and Neighboring Areas = McCown s Longspur, Sage Sparrow, and Yellow-billed Cuckoo. ** Status and Habitat Association: B = Direct evidence of breeding; b = Indirect evidence of breeding; t = No evidence of breeding; Sens = Flathead National Forest Sensitive Species; OG = Old growth Associated Species; R = Riparian Associated Species. Two especially important habitats to nesting birds are: 1) riparian habitat, because of the availability of water and variety of plant communities, and 2) old growth habitat, which has the highest density and diversity of birds nesting in tree cavities (McClelland and Schmidt 1995). Riparian habitats occur along lakes, rivers, streams, springs, and seeps where the vegetation and microclimate are influenced by year-round or seasonal water and associated high water tables. Most plant and animal species in riparian habitat are more productive and diverse than on nearby uplands, making these areas very important to many wildlife species. Within the Flathead National Forest, 36 bird species are recognized as dependent upon riparian marsh habitat and 23 bird species are recognized as dependent upon forested riparian areas (LRMP, Planning record [g], 1980). These include threatened and sensitive species (bald eagle, harlequin duck, common loon), and some neotropical migrants. The harlequin duck and common loon must have clear, clean water for their aquatic food sources

3 Timber harvest, fuel reduction, insect epidemics, and fire can impact wildlife using riparian habitats by causing changes in plant species, hiding cover, downed wood recruitment, water temperature, shading, humidity, erosion, water quality, and predatorprey interactions. Bird populations that breed in the western United States appear to be suffering from forest fragmentation in breeding habitat (Rotenberry, et al. 1995; Hejl, et al. 1995; Hejl, et al. 2002; Turcotte and Desrochers 2003). Problems associated with forest fragmentation include overall habitat loss, increase in high-contrast edge habitat and edge effects, isolation effects, and increased vulnerability to predators (Finch 1991; Turcotte and Desrochers 2003). The cowbird has a negative impact on many neotropical migratory birds, either through brood parasitism (cowbirds lay eggs in another birds nest) or nest predation. Brownheaded cowbirds benefit from forest fragmentation, particularly where livestock graze within about five miles. Cowbirds have been documented within the project area through reported field observations, bird point-counts, and through land bird monitoring pointcount transects conducted by the Avian Science Center. Tewksbury et al. (1998, 2006) monitored 1916 nest sites to study the effects of landscape-level fragmentation on nest predation and brood parasitism in riparian areas of western Montana. They found that the strongest predictors of parasitism were the abundance of farms and houses, not forest cover. They concluded that the effects of fragmentation are dependent on the habitat structure, landscape context, community of other nest predators (such as red squirrels), and bird species being parasitized. A study by Bull et al. (1995) showed that cowbird use more than doubled in an old growth stand treated for fuel reduction. However, when sufficient downed woody material, residual understory trees, and wind-firm live trees and snags are available, timber harvest can maintain adequate habitat values for birds. Overall, the project area provides a considerable diversity of forested habitats, including old growth, snag/downed wood habitats, and a variety of riparian areas. For more information about wildlife habitat conditions across the Flathead National Forest relevant to neotropical migrants, see the Final Environmental Impact Statement for the Flathead's LRMP Amendment 21 (USDA 1999a) The riparian influence area (RIA) within the MFFR Project Area includes lands immediately adjacent to two major drainages; Bear Creek and the Middle Fork Flathead River. Most of the forest in the RIA are in a mid-successional stage resulting from past fires. Some of these stands have scattered, old fire survivors in the overstory. Young, early successional seedling/sapling forests and stands in a late successional stage make up the remainder of the RIA. The RIA includes lodgepole pine, spruce and sub-alpine fir, and larch/douglas-fir forest types, as well as non-forest types including water, rock, or barren ground

4 Environmental Consequences The direct and indirect effects on the riparian influence area (RIA) and old growth habitat are discussed below. Effects on smaller riparian features are described in the analysis of fisher habitat. Alternative 1 (No Action) Direct, Indirect, and Cumulative Effects No additional actions, such as timber harvest, fuel reduction, road construction, or road reclamation, are proposed with this alternative. Overall, this alternative would leave habitats across the analysis area to continue with relatively natural processes. Trees and snags would provide potential habitat for many cavity nesting species, and subsequently for secondary cavity nesters, including some neotropical migrants. The probability of fire would increase, improving habitat for some neotropical migrants and reducing the tree and understory canopy important to others. Alternative 2 (Proposed Action) Direct and Indirect Effects With the exception of hand fuel reduction proposed activities in unit 8, harvesting and prescribed burning would not occur in old growth stands. Riparian features would be protected by INFISH buffers and layout of units to avoid the RIA (see Design Criteria; chapter 2). Most proposed treatment areas that are within field verified riparian landtypes, so riparian vegetation needed by birds would be maintained. Unit 5 is proposed for 60 acres of group selection harvest within a 112 acre area. This unit has high value for birds due to the presence of large cottonwood trees and abundant wet site shrubs. Harvest throughout this stand would remove habitat for neotropical migrants. Proposed project implementation could directly affect neotropical migratory birds through disturbance of habitat changes that may disrupt nesting and foraging activity, or could directly contribute to nest failure. Displacement of bird species would be short-term, probably one year (season) or less. Potential negative affects to nesting would be decreased by logging restrictions from April 1 to June 30 (see Design Criteria, Chapter 2). Stands proposed for hand thinning and group selection harvest would have sufficient downed woody material, residual understory trees, live trees and snags to maintain adequate habitat values for birds. Proposed seedtree and shelterwood harvest units would increase fragmentation and new edge habitat, increasing the likelihood of parasitism or predation of songbird nests in areas adjacent to homes and agricultural lands. This effect would last up to 20 years, when open stands would be expected to close in with dense stands of young conifers

5 Cumulative Effects The MFFR project area is approximately 32,000 acres in size and is adjacent to the Great Bear Wilderness and Glacier National Park, where natural ecosystem processes prevail. Habitat corridors through the public land portions of the project area are wide, unfragmented, and provide a diversity of habitats including snags and down woody material. Unless wildfires occur, this habitat is expected to be available a long into the future. In parts of the project area, fragmentation has resulted from habitat alteration due to past timber harvest and fires. The impact of these activities upon forest structure was developed as part of the old growth and lynx habitat analyses (see Forest Vegetation and Wildlife M1 sections in project file). This analysis showed that existing areas of old growth habitat have good block size and connectivity throughout the analysis area. The connectivity of riparian habitat along the Middle Fork Flathead River has been promoted by its designation as a Wild and Scenic River. The MFFR project area contains abundant riparian landtypes in a relatively undisturbed condition. Saab and Rich (1997) list threats, species, and relevant habitats of concern for neotropical migrants on the scale of the Columbia River Basin. Any changes in nest parasitism brought about by the proposed project would be expected to be relatively minor and of short duration, but would be cumulative to that already occurring. Since some of these units are adjacent to private land used for cattle or horse grazing (which increases foraging opportunity for cowbirds), current parasitism by cowbirds is likely. However, given the scale of treatments, the existing natural openings throughout many harvest units, the large proportions of undeveloped public land in and near the project area, and the scale of on-going human influences on adjacent private lands, the cumulative influence of proposed activities would lead to a relatively minor contribution to parasitism in the area. Proposed activities would not be expected to create significant adverse impacts migratory bird species. Regulatory Framework and Consistency All alternatives are consistent with NFMA biodiversity requirements for wildlife. For information about and consistency with INFISH requirements, Montana's House Bill 731 (the Streamside Management Zone act), and other regulatory requirements specific to aquatic systems, see the Hydrology section of this chapter. The Forest Service s Landbird Conservation Strategic Plan (2000), Executive Order (2001), the Partners in Flight habitat Conservation Plans for birds, and the Partners in Flight North American Landbird Conservation Plan (2004) all reference goals and objectives for integrating bird conservation into forest management and planning. In 2008, a Memorandum of Understanding was signed between the USDA Forest Service and the US Fish and Wildlife Service to promote the conservation of migratory birds. The intent was to strengthen migratory bird conservation through enhanced collaboration and cooperation between the Forest Service and the Fish and Wildlife Service as well as 3-133

6 other federal, state, tribal, and local governments. Within the National Forests, conservation of migratory birds focuses on providing a diversity of habitat conditions at multiple spatial scales and ensuring that bird conservation is addressed when planning for land management activities. The Migratory Bird Treaty Act covers many ground-nesting and shrub-nesting birds. Under the Act, taking, killing or possessing migratory birds, including nests and eggs, is unlawful. A list of Neotropical migrants protected by the Migratory Bird Treaty Act is provided in 50 CFR Some migratory birds are covered by state hunting regulations; others are protected by non-game status by the Montana Department of Fish, Wildlife, and Parks. The flammulated owl and the peregrine falcon are sensitive species; habitat considerations are summarized in Table-23 of the introduction. Effects determinations are noted in Table 3-24 in the Regulatory Consistency and Framework section for Sensitive Species. Upon review of the information regarding neotropical migratory birds, no substantial loss of migratory bird habitat is expected from alternative 2. Potential negative affects to nesting would be decreased by logging restrictions from April 1 to June 30. The project will not adversely impact migratory landbird species or their associated habitats. Potential impacts to migratory species would be minimized through the adherence of LRMP Standards and Guidelines for snags/down woody debris, riparian reserve buffers, and limited ground disturbance. The intent of the Migratory Bird Treaty Act, the 2001 Executive Order, and the 2008 MOU to conserve and protect Neotropical migrants would be met under all alternatives. All alternatives would be consistent with NFMA direction for diversity of plant and animal communities and ecological sustainability