MIGRANT SHRIKE 153 



"in September and October, which involves the body plumage, ter- 

 tiaries, wing coverts and tail, but not the rest of the wings. Similar 

 to previous plumage but grayer above and the venniculations absent 

 or very indistinct on the breast. Above, plumbeous gray, paler on 

 rump, the posterior scapulars white. 



"Wings and tail black except for the brown juvenal primaries, sec- 

 ondaries and primary coverts, the lesser coverts plumbeous, white tips 

 to the new tertiaries and white terminal spots on the lateral rectrices. 

 Below, dull white with dusky venniculations sometimes faintly indi- 

 cated. A broad, black bar through the eye." 



He says that in both young and old birds there is a partial prenuptial 

 molt in February and March, "which involves chieily the chin, throat 

 and head, and a fevv' scattering feathers elsewhere, but neither the 

 wings nor the tail." All individuals have a complete postnuptial molt, 

 mainly in September, but sometimes beginning in July or August, 

 and sometimes prolonged into October or even November. 



Food. — The migrant shrike eats fewer mice and birds and more 

 insects tlian the northern shrike does. The northern bird is witli us 

 in the States only in winter, when insects are scarce; but the mi- 

 grant finds insects abundant in its summer home and fairly common 

 in the south in winter. Shrikes are almost omnivorous and Avill take 

 what animal food is most readily available. The following report by 

 F. H. King (1883) on the contents of stomachs collected in Wisconsin 

 is interesting as showing the variety of food eaten and the proportions 

 of each: "Of fifteen specimens examined or observed, one had eaten 

 seven moths ; three, five caterpillars ; two, eleven diptera, among them 

 five crane-flies; nine, eighteen beetles, among them three ground- 

 beetles, three carrion-beetles and two leaf-chafers; five, twenty-two 

 grasshoppers ; two, two crickets ; three, six May-flies ; two, four snails. 

 Two had killed three birds — one, a Canarybird, and one, two Warb- 

 lers; two, two mice. One of the birds was shot while in the act of 

 killing a meadow mouse [Arvicola riparia) ." 



William Brewster (1938) saw a migrant shrike impale a bank 

 swallow, a bluebird, and a pickerel frog. Others have reported small 

 sparrows as killed by this shrike, as well as shrews, snakes, lizards, and 

 tree frogs. But all the vetebrates eaten form but a small proportion 

 of the food. Invertebrates, mainly insects, form the bulk of the food, 

 of which Orthoptera make up the largest item ; but beetles, both bene- 

 ficial and harmful, cutworms, butterflies, cicadas, wasps, and spiders 

 are also included in the food. 



Frank T, Noble (1902) published an interesting account of a mi- 

 grant shrike that met its match in an attempt to capture a small 

 gartersnake, about 18 inches long. The snake had wound itself 

 around the bird's neck and had nearly strangled it. Mr. Noble was 



843290—50 11 



