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Planning for the expansion of biomass production in the Midwest: Remaining wildlife neutral. JoAnn Hanowski Natural Resources Research Institute University of Minnesota-Duluth. Remaining Wildlife Neutral. No net loss in Conservation Reserve Program acreage
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Planning for the expansion of biomass production in the Midwest: Remaining wildlife neutral JoAnn Hanowski Natural Resources Research Institute University of Minnesota-Duluth
Remaining Wildlife Neutral • No net loss in Conservation Reserve Program acreage • Establish landscape appropriate biomass crop • Understand habitat change implications from upland brush and timber harvest residue removal • Create positive habitat change for wildlife in under-utilized ecosystem types, lowland brush
No net loss in CRP acreage • CRP protects almost 40 million acres of highly erodible farmland • CRP has restored over 1.8 million acres of wetland • CRP produces 2.1 million ducks/year • CRP provides critical habitat for 100’s of wildlife species
Establish landscape appropriate biomass crop • Avoid planting hybrid poplar in open landscapes • Switchgrass managed properly could have positive impacts on wildlife • Switchgrass mix would provide better wildlife habitat than monoculture
Breeding birds and hybrid poplar • What are the pressing issues with wildlife (specifically breeding birds)? • Studies completed in Minnesota in the last decade • Developed recommendations for hybrid poplar plantations • Pulp prices have made it difficult to utilize hybrid poplar as an energy source
Study Sites • Large plantations (up to 300 acres) located in western and southwestern MN • Eleven plantations were surveyed over 7 years • Oldest plantation was 11 years (in 2001)
Habitat • What species respond positively to presence of plantation habitat? • What species are replaced when existing land-use is converted to plantation? • How can we increase plantation diversity?
Community response • Total number of individuals increase as plantations age • Species richness does not change much, usually 4 to 6 species
Habitat guild response • Composition of bird community changes as plantations age • Young plantations have species associated with open and shrub habitats • Number of forest dwelling individuals increases with age
Species response • Species that colonize plantations are generally found in adjacent habitats • Young plantations have lots of sparrows and blackbirds • Beginning to see vireos and warblers in older plantations and some permanent residents
Bird species replaced • Dependent upon habitat • Replacement of cropland least amount of impact • Replacement with “good” CRP most impact
Pheasants Forever? • Initial concern that pheasants would be negatively impacted • We observed pheasants in summer and winter • Likely not affected unless large percentage of area is in plantation
Landscape Context • Species that colonize plantations are dependent upon landscape context • Plantations in a predominantly agricultural landscape are colonized by mostly open country and shrub bird species • Plantations in forest landscapes are colonized earlier by forest birds
Habitat quality • Longevity of habitat for individual species is short • Community turnover is almost 50% each year • Productivity of individuals is questionable • Are plantations largely sink habitats?
Are plantations attractive hazards? • Open tree architecture, lack of understory and ground cover may result in increase predation of bird nests and increased parasitism rates by Brown-headed Cowbirds
Artificial nest studies • Plantation and surrounding habitats • Results indicated that predation rates were independent of habitat type and distance from plantation edge • Predation rates were high on some sites, likely due to local predator populations
Recommendation: What to avoid • Replacement of “good CRP habitat” and highly erodible sites • Fragmentation of open habitats especially in areas with sharp-tailed grouse and prairie chickens • “Large” areas of single-aged plantations
Understand habitat change implications from upland brush and timber harvest residue removal • Fire suppression has resulted in buildup of brush in forest ecosystems-create guidelines for habitat restoration • A percentage of residue from timber harvest could be removed from site-create guidelines
Minnesota guidelines: Woody Biomass Removal • Retain timber harvest guidelines for retention trees, snags and CWD • Old guideline for slash- leave scattered on site • New guideline: Leave 20% of tree tops and limbs scattered on site • Issue for certified land owners to ensure that operations are sustainable
Create positive habitat change for wildlife in under-utilized ecosystem types, lowland brush • Brush management for open country species includes shearing and burning brush on site which cost money • Opportunity to harvest biomass from these sites and have positive impact on wildlife
Lowland Brush Harvest • Positive impact on open country birds • Negative impact on other species • Planning needs to be done on landscape level to get best results for species with complicated life histories (Sharp-tailed grouse)
Identify species of concern • Partners in Flight species of concern • 4 species, Veery, Rose-breasted Grosbeak, Golden-winged Warbler and Canada Warbler, use upland and/or lowland brush habitat
Summary: remaining wildlife neutral • Control crop expansion on CRP lands (corn and soybeans) • Establish landscape suitable biomass crops and diverse species crops if possible • Exploit woody biomass on timber harvest sites with a plan • Explore habitat restoration possibilities with upland brush removal • Plan landscape level lowland brush harvest to benefit species of concern