Avian responses to late-season grazing in a shrub-willow floodplain
Published source details
Stanley T.R. & Knopf F.L. (2002) Avian responses to late-season grazing in a shrub-willow floodplain. Conservation Biology, 16, 225-231.
Published source details Stanley T.R. & Knopf F.L. (2002) Avian responses to late-season grazing in a shrub-willow floodplain. Conservation Biology, 16, 225-231.
This study is summarised as evidence for the following.
Employ grazing in artificial grasslands/pasturesAction Link
Employ grazing in artificial grasslands/pastures
A controlled before-and-after trial in 1981-1986 in Arapaho National Wildlife Refuge, Colorado, USA (Stanley & Knopf 2002), found few differences in overall bird density changes between two lightly grazed and two ungrazed pastures. However, for three of the nine species studied in detail, and for all three guilds examined, there were differences between treatments. Red-winged blackbirds Agelaius phoeniceus and American robins Turdus migratorius increased more on grazed pastures, as did species able to tolerate a moderate range of environmental conditions. However, willow flycatchers Empidonax traillii and species able to tolerate either a wide range of conditions or a very narrow range may have increased more on ungrazed pastures. The authors note that evidence for changes in most species was weak. The grazed pastures were grazed in August and September (with 2.4-3.5 animal-unit-months/ha) and then rested for 34 month.