Date of this Version
Nebraska Bird Review (June 1987) 55(2).
Insect biomass was estimated for crops grown on an organic, a dryland, and an irrigated farm from 1 June to 15 July, the time period assumed important for Ring-necked Pheasant (Phasianus colchicus) nesting and chick dependence on insect food. Differences due to farming system were not detected. Total insect biomass production during the season was 2,555, 2,173, and 338 mg per square m for oats-sweetclover, oats, and sweetclover, respectively. Leafhoppers were the most abundant insects in oats and oats-sweetclover, with plant bugs the most abundant in sweetclover. Mean standing crop biomass (mg per square m) of only those insects acceptable as food for chicks was oats-sweetclover (509), oats (413), sweetclover (397), wheat (247), alfalfa (163), soybeans (46), and corn (38). Oats-sweetclover and oats were the only crops providing both nesting habitat and insect food for pheasant chicks.
Insects are essential as food for Ring-necked Pheasant chicks. It is generally believed that oats (Avena sativa) or oats-sweetclover (Melilotus officinalis) provide adequate amounts of insects (Warner 1984) but few quantitative data are available. Whitmore et al. (1986) confirmed that these crops support many insects eaten by chicks.
Intensive agriculture, with use of commercial fertilizers, has resulted h a decline in the area planted to oats-sweetclover. Warner et al. (1984) associated the declining Pheasant population in Illinois with the trend toward monoculture in farming. The Nebraska Game and Parks Commission sponsors a habitat program in which farmers and ranchers receive payment for growing oats-sweetclover for a 2-year period. Sweetclover is interseeded in oats the first year and harvest of the oats crop is permitted. Sweetclover and oats stubble provide habitat during the second year. To evaluate this program, we determined the insect biomass available to pheasant chicks in crops grown in three farming systems.