The population of ring-necked pheasants in California and Oregon's Klamath Basin have declined markedly in recent decades. The pheasant harvest at Tule Lake National Wildlife Refuge (TLNWR) and Lower Klamath NWR (LKNWR) declined from 7,707 in 1974 to less than 1,000 1987 based on check station counts. Gradual changes in agricultural land use practices have been recognized as the primary reason for these declines. Small diversified farms have been incorporated into larger farms which utilize larger tracts of land for crops. Springtime burning to remove residual cover also reduces available pheasant nesting and brood cover.

We used radio telemetry to study a population of ring-necked pheasants associated with intensively farmed agricultural land at TLNWR from the spring of 1991 through the spring of 1993 and compared those findings with a nearby population at LKNWR which was not intensively farmed. We did a comparative study at the two refuges to 1) estimate hen and brood survival, 2) evaluate hen body condition (weight and length), and 3) determine placement and success of nest sites in relation to available cover.

Inadequate nesting cover was responsible for extremely low nest success early in the nesting season at LKNWR. Later in he season at TLNWR, spring planted crops provided cover to conceal nesting and renesting hens; however, only .07 young were produced per hen during the study. The extremely low reproductive rates were well below those required to maintain a stable population. Hard winters periodically reduce the pheasant population in the Klamath Basin and again greatly reduced numbers during the last year of this study. Unfortunately, pheasant populations declined under the conditions found during the study and were unable to recover from the hard winter of 1992 to 1993. Mean body mass and length of adult hen pheasants at TLNWR, which is intensively farmed, were less than those for hens at LKNWR which is not intensively farmed. Results of our study suggest the TLNWR hens may have been nutritionally stressed and that the amount and distribution of vegetative cover needs to be improved at TLNWR. Habitat management of edge cover along agricultural crops should feature perennial grasses and legumes with small tracts of land interspersed throughout the agricultural fields to provide alternative cover for wildlife in general including pheasants.

Learn More by Reading the Full Report: Groves, R.A., Buhler, D.R., Henny, C.J., and Drew, A.D., Cover Condition and Its Influence on Nesting Success of the Ring Necked Pheasant, Northwestern Naturalist. 82:85-101. 2001.

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