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Abstract.- I observed American Robins (Turdus migratorius), n~100, foraging for worms on the lawns of West Cedar Beach Park in Allentown, PA, USA, 1992-1993. Birds tended to forage straighter, and in shorter bouts, after a successful encounter with prey (Median Test, N=1, x2= 0.1, p= 0.05, df=1), as opposed to above and below 180 degrees (median= 140 degrees) on a protractor (N=1, x2=4.11, p=0.05, df=3.8). Angles measured /x= 134, SE+/- 13, and cv= 39%. They often foraged with Eurasian Starlings (Sturnus vulgaris) and purple race Common Grackles (Quiscalus quiscula quiscula), the latter which kleptoparasitized them, on moist spring and fall short grass lawns. Such guilds contained American Crows (Corvus brachyrynchos) as well if the lawns were expansive. All of these species are classes as omnivores. Birds were relentless in drought conditions and did find worms. Probing on a sample plot near a nest increased during the nestling and fledgling stages during two broods during May and June. One robin was seen eating white proso millet. The birds seem to use geometrical foraging for prey optimization. Suburban habitat patches may require optimal foraging, where the bird is an opportunist when prey is scarce, but does the opposite and awaits the choiciest morsals when the patch is flooded by prey. Moving in flocks, the Information Center Hypothesis makes most sense according to my observations because once a patch because used up, usually the fock moved together to another patch, possibly following initial explorers. Robins and other passerines may forage man-made lawns because morphologically their legs and feet are too small to forage in fields.