. Birds of a Maryland farm : a local study of economic ornithology . d swallow,Bank vireo. Warbling vireo. White-eyed vireo. Yellow warbler. Magnolia warbler. black-poll warbler. Louisiana water-thrush. Maryland yellow-throat Chat. Redstart. Catbird. Long-billed marsh wren. < Hive-backed thrush. In this mischief the flycatchers are oy all means the greatestoffenders, the .swallows next. and. less generally but still noticeably,the warblers next. Of all the flycatchers the wood pewee
. Birds of a Maryland farm : a local study of economic ornithology . d swallow,Bank vireo. Warbling vireo. White-eyed vireo. Yellow warbler. Magnolia warbler. black-poll warbler. Louisiana water-thrush. Maryland yellow-throat Chat. Redstart. Catbird. Long-billed marsh wren. < Hive-backed thrush. In this mischief the flycatchers are oy all means the greatestoffenders, the .swallows next. and. less generally but still noticeably,the warblers next. Of all the flycatchers the wood pewee appeared to be the most active and per-sistent in tins wasps are not usu-ally so alert and swift asmany other insects: there-fore they are easy of the class are ichneu-mon flies (Ichneumonidaefig*. 13). Somewhat morethan a tittb of tbe birds thathad taken parasitic , bad fed on a cer-tain black wasp. Tvphia inor-nata, which. is a vigorousenemy of the larva of theMay-beetle. These waspsthat it is not unnatural that a. ■Ichneumon By (after Bo ward; loaned byDivision f Bntomolog are so common in May and June good many should fall prey to birds. The only other noticeably abundant parasitic Hymenoptera were some very large bracomds [X8ECT FOOD. 41 (Mi lanobrctcori), of which at any time during the first pari of September,. a dozen could have been collected within a few minutes. FieldBparrows and probably other birds consumed them freely, though asa rule parasitic Hymenoptera arc eaten only in small numbers. Many of these useful species appear too late in the season to be ofmuch effect. An attempt was made to measure the evil effects of theirdestruction by observing how far they were parasitizing abundantinsect pests, but conditions were unfavorable and adequate resultswere not obtained. The white grub of the May-beetle was not presentin numbers sufficient to furnish evidence. Hie tobacco worm was par-asitized by braconids t some ext
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectbirdsma, bookyear1902
