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The epaulets of male Red-winged Blackbirds (Agelaius phoeniceus) function in both intersexual and intrasexual contexts, but there is little evidence that they covary with reproductive success in this well-studied species. We used path analysis of male/territory traits, mating success, and reproductive success of unmanipulated males to estimate current directional selection. Territory size had a positive effect on number of within-pair mates. Number of extra-pair mates had a positive effect on number of extra-pair fledglings, and number of within-pair and extra-pair fledglings had positive effects on total number of fledglings. We also reddened epaulets of free-living territorial males to determine whether manipulated and control males differ in territorial behavior, mating success, or reproductive success. Compared with control males, males with reddened epaulets incurred elevated rates of trespassing and territorial challenges, lost their territories more often, and were unable to produce extra-pair offspring. Despite these differences, however, the realized reproductive success of experimental and control males did not differ significantly, perhaps because males with reddened epaulets devoted more time to anti-predator vigilance and were more aggressive toward a simulated predator than were control males. An apparent lack of current sexual selection on epaulet color may be a form of counter-balancing sexual selection in which male aggression against redder epaulets opposes female preference for redder epaulets, or it might be the result of males compensating for lost extra-pair fertilizations by increasing their parental care.

In an effort to determine type, extent, and distribution of agricultural damage by blackbirds, county-wide damage appraisals were conducted in the fall of 1960. Crops checked included corn, peanuts, and milo. Based on the 96 fields examined throughout Nansemond County, the average monetary loss to the corn crop was slightly less than $.05 per acre. This loss can be reduced by planting a variety with a high degree of ear drooping and planting as early as possible. The peanuts appeared to be the crop most heavily damaged. An estimated 50 per cent of the crop was picked before blackbirds arrived. Of the part of the crop left exposed after the arrival of the blackbirds, only a small portion sustained damages amounting to above $5 per acre. By harvesting peanuts at an early date, losses to blackbirds can virtually be eliminated. The 1960 milo crop was not damaged by birds nearly so severely as previous crops were reported to have been. Anthracnose, a fungal disease, accounted for about 86 per cent of the damage previously called "bird damage." An estimated 15 per cent of this crop was destroyed by anthracnose, insects, and birds. In the case of all three crops, it was noted that the first and most severe damage was to those fields nearest nesting and roosting habitat. / Master of Science