A Repellent for Protecting Corn Seed from Blackbirds and Crows

Abstract

Methiocarb [4-(methylthio)-3,-5-xylyl N-methylcarbamate] was tested as a seed treatment for repelling blackbirds and crows (Corsus sp.) from sprouting corn in South Carolina. The test was conducted on eight fields within a 0.25-square-mile area. Marked repellency occurred; sprout damage averaged 44 percent in the control fields and 0.3 percent in the fields treated with methiocarb. 50 percent of the birds tested ) was 1.0 mg/kg for red-winged blackbirds ( Agelatus phoeniceus ) . In a later report ( E. W. Schafer 1971, unpublished report, Denver Wildlife Research Center), the acute oral LD50 was given as 4.6 mg/kg for redwings, 10 mg/kg for common grackles (Quisculus qu1rscula ), 24 mg/kg for bobwhite quail (Colinus virginianus), 10 mg/kg for mourning doves (Zenaidura macroura), and 56.2 mg/kg for pheasants. Our report describes a test of methiocarb as a bird repellent on planted corn seed. The test was made in the spring of 1969 under conditions of heavy pressure by redwings, common grackles, and crows. Since sprout damage by these species is particularly prevalent in areas along the eastern seaboard wherever corn is grown next to water, these tests were conducted at Santee National Wildlife Refuge in South Carolina. Here corn is grown adjacent to the Santee-Cooper reservoir, and the damage is severe at times. The chemical methiocarb (DRC-736) was provided by Chemagro Corporation, Kansas City, Missouri. The use of trade names does not imply endorsement of commercial products by the