s that are typical of the local native shrub/grassland habitat, such as green-tailed towhees and vesper sparrows. In contrast, rural developments had higher densities of nest predators, such as the black-billed magpie, and of birds that are usually uncommon to the area, such as Bullock's oriole, a tree-nester that is presumably attracted by the landscaping trees.

Moreover, ranches had more native plant species and fewer non-native plant species than rural developments and reserves. Altogether the ranches had only half as many non-native plant species as the rural developments, and only two-thirds as many as the reserves (11 vs. 23 and 17, respectively). In addition, the coverage of cheatgrass, the most common non-native plant, was lower on ranches than on rural developments or reserves (14%, 18% and 22%, respectively).

"Ranches can be more effective than reserves at maintaining native biotic communities," say Maestas and his colleagues. Reserves may be inadequate because most are in harsher environments with higher elevations and poorer soil. Moreover, the reserves studied have extensive trail systems that could facilitate the spread of non-native plants.

'"/>

Contact: Jeremy Maestas
jeremy.maestas@ut.usda.gov
801-377-5580 X32
Society for Conservation Biology
23-Sep-2003

Page: 1 2
Related biology news :

1. New framework for biodiversity conservation
2. Leading scientists design new framework for biodiversity conservation
3. Society for conservation biology conference
4. Energy conservation targets hit by notions of comfort
5. Field Museum gives Parker/Gentry Award to Chinese conservationist
6. Study examines future of species extinction, conservation
7. New study confirms conservation surgery is safe for BRCA breast cancers
8. Does shade coffee help or hinder conservation?
9. Not batty conservation
10. Energy companies, conservation groups issue biodiversity recommendations for oil & gas development
11. Borneo elephants: A high priority for conservation