Record Details
Nesting ecology of mallards in the Willamette Valley of Oregon
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Nesting ecology of mallards in the Willamette Valley of Oregon |
| Names |
Rickerson, Eric V.
(creator) Jarvis, Robert L. (advisor) |
| Date Issued | 2001-07-23 (iso8601) |
| Note | Graduation date: 2002 |
| Abstract | Although widely studied in many portions of North America, little is known about the specific habitat requirements of mallard ducks (Anas platyrhynchos) during the breeding season in western Oregon. I radio-marked 72 female mallards in the Willamette Valley of Oregon in March-April 1995-96 to document wetland habitat selection during pre-nesting and nesting phases, nesting cover selection, nesting and female success rates, nesting chronology, and survival of females during the pre-nesting and nesting periods. Wetland habitat selection was higher for seasonal riverine and permanent lacustrine habitats during the pre-nesting and nesting periods. Uncultivated upland and wetland habitat nesting sites with a strong cover component had a higher selection ranking compared to agricultural cropland and ash-cottonwood riparian. The reproductive period was 107 days beginning in early-March and concluding in late-June with the peak of nest attempts occurring around May 9. Nesting effort was low with 38.4% of females failing to attempts at least one nest. Nest survival probabilities ranged from 0.106 in 1995 to 0.216 in 1996 with a pooled estimate of 0.186 (95% C.I.=0.122-0.298). Mammalian predation accounted for 84% of nest failures. Overall female success was 40.5% and differed between first year (SY) and second year and older females (ASY). Female survival probabilities ranged from 0.5 11 in 1995 to 0.733 in 1996, with a pooled estimate of 0.668 (95% C.I.=0.5370.842). |
| Genre | Thesis/Dissertation |
| Topic | Mallard -- Habitat -- Oregon -- Willamette River Valley |
| Identifier | http://hdl.handle.net/1957/20234 |
