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| Title | The Spoonbill, Vol. 44, No. 11, November 1995 |
| Publisher | Outdoor Nature Club |
| Date | November 1995 |
| Subject.Topical (LCSH) |
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| Subject.Geographic (TGN) |
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| Genre (AAT) |
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| Language | English |
| Type (DCMI) |
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| Original Item Location | ID 2007-023, Box 12, Folder 17 |
| ArchivesSpace URI | /repositories/2/archival_objects/9880 |
| Original Collection | Outdoor Nature Club Records |
| Digital Collection | Outdoor Nature Club Newsletters |
| Digital Collection URL | http://digital.lib.uh.edu/collection/2007_023 |
| Repository | Special Collections, University of Houston Libraries |
| Repository URL | http://libraries.uh.edu/branches/special-collections/ |
| Use and Reproduction | In Copyright |
| File Name | index.cpd |
| Title | Image 1 |
| Format (IMT) |
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| File Name | uhlib_2007_023_b012_f017_011_001.jpg |
| Transcript | The Volume 44, No. 11 November 1995 Spoonbil Published by The Ornithology Group, Outdoor Nature Club, Houston Uncertain Future for Swainson's Hawks by Brian Woodbridge Swainson's Hawks (Buteo swainsoni) are long-distance neotropical migrants, breeding in grassland and shrub steppe habitats of the U.S. and Canada, and wintering in similar habitats in southern South America. Habitat modification in breeding areas and in Latin America, environmental contaminants, shooting along migration routes and pesticide contamination have contributed to declines in western U.S. populations of this species. Although habitat relationships on their breeding range are understood, little is known about habitat use or potential threats to the Swainson's Hawk in Latin America. Using satellite-capable radio transmitters attached to two wild Swainson's Hawks, the Forest Service monitored the hawks' migratory pathway from northern California through Mexico, El Salvador, Nicaragua, Brazil and Bolivia to Argentina. The hawks ultimately settled in the northern part of the province of La Pampa, near the town of Colonel Hilario Lagos. In January and early February 1995, we visited Argentina to investigate the species' behavior and habitat use, and to establish contact with researchers and governmental agencies involved in bird conservation. Based on the latest telemetry readings from our two hawks, we established a study area encompassing 6400 square kilometers (4000 square miles) and began mapping the species' foraging areas and roost sites. Our study area supported a spectacular concentration of Swainson's Hawk. We located several communal night roosts containing from 2000 to over 7000 hawks, and many smaller roosts containing less than 200 hawks. During the day, we observed large flocks of hawks (from 60 to thousands) foraging for insects in the air and on the ground, in pastures and cultivated fields. The primary prey appeared to be a small grasshopper, locally known as "tucura" (Dichronplus spp.). Night roosts were typically in groves of eucalyptus trees planted at farm entrances and headquarters. Unfortunately, in La Pampa, high-input agricultural practices producing such commodities as corn, soya and sunflower are swiftly replacing the traditional low-intensity agricultural practices of cattle grazing and hay production due to worldwide market trends. (See Swainson 's on Page 5) |