In the oft-rainy South Puget Sound region of western Washington, a highly threatened, dry prairie ecosystem persists on droughty soils across a patchwork of prairie preserves and grazed working lands. With recent ESA listings resulting from habitat loss, a team of farmers, researchers, and county planners is seeking to build collaboration across conservation and agriculture. They’re doing this by incorporating working lands conservation into a Habitat Conservation Plan that will protect, among other species, the Taylors checkerspot butterfly, Mazama pocket gopher, and Oregon vesper sparrow.
The team, composed of personnel from the Center for Natural Lands Management, Washington State University, the University of Idaho, the Natural Resources Conservation Service, Thurston County Planning, and four local ranchers, is aiming for a ‘lemonade from lemons’ approach.
With prairie habitat reduced to 1-3 percent of its historic range, and Thurston County farmland reduced by 100,000 acres (65%) since the 1950s, working lands conservation could expand (and connect) conservation acreage outside of preserves, compensate landowners for conservation work through easements and other tools, and provide a means to staunch farmland loss through voluntary sale or transfer of development rights.
By year two in a three-year study, the team documented gopher occupancy, butterfly behavior, forage production, and native species diversity on three working ranches and three prairie preserves. Eighteen acres of grazing lands were seeded to important native butterfly host and nectar plants, and a trial rotational grazing system was introduced on one ranch. Results from the first two years indicate that working grazed prairies provide significant conservation value necessary to protect threatened and endangered South Sound prairie species. Rates for gopher occupancy were as high in grazed as ungrazed systems, while native species richness at ranch sites still remained much lower (2-10 species on average at ranch sites compared to 15-21 species on average in native prairies) as the seeded plants become established.
The “conservation grazing” approach implemented by the team consisted of seeding native prairie species, implementing managed intensive grazing methods such as retaining a minimum stubble height, and providing a spring “rest period” during which grazing is deferred from mid-April to mid-June to allow native prairies plants to flower and set seed. Importantly, forage availability remains equally high in areas treated with these methods as it is in traditionally grazed areas, maintaining the ranchers’ bottom line.
By the end of the project, the team hopes the data will allow county planners to expand the use of working lands for species protection, while providing farmers with compensated options for conservation work.
For additional information on the project: https://extension.wsu.edu/thurston/agriculture/on-farm-conservation/prairie/
The Center for Natural Lands. Management prairies website provides excellent background: http://www.southsoundprairies.org/
This article was provided courtesy of Stephen Bramwell.