. The relation of birds to the cotton boll weevil . all butone of them had eaten boll weevils, the majority having takennothing else. Many of the stomachs were crammed full of theweevils. The largest number eaten by a single bird was -L7. whilemany others had taken from 20 to 30 at a meal. The total numberdestroyed by these thirty-five birds was 638, an average of 18 weevilsto each bird. It is of course impossible to estimate with any degree SWALLOW 13 of accuracy the number of cliff swallows in the State of Texas duringthe month of September, bul a very conservative estimate of thenumbe
. The relation of birds to the cotton boll weevil . all butone of them had eaten boll weevils, the majority having takennothing else. Many of the stomachs were crammed full of theweevils. The largest number eaten by a single bird was -L7. whilemany others had taken from 20 to 30 at a meal. The total numberdestroyed by these thirty-five birds was 638, an average of 18 weevilsto each bird. It is of course impossible to estimate with any degree SWALLOW 13 of accuracy the number of cliff swallows in the State of Texas duringthe month of September, bul a very conservative estimate of thenumber passing over the town of Victoria each day of the migrationis 10,000. Allowing but one meal a day ami assuming that each birdconsumed on an average IS weevils per day for the period of sixdays during which the flight was under observation, we find thatthese swallows destroy in one week in a single county more than amillion weevils! And this vast number is destroyed without a dol-lars expense to the cotton grower. In view of this good service the. Fig. 4.—Barn swallow. folly of destroying the nests of swallows and of shooting the birdsbecause they harbor insects is apparent, especially when it is remem-bered, as stated above, that the swallow parasites are not to be fearedby man. Barn sivallow.—Barn swallows are common summer residents inthe western portion of Texas, but for some unknown reason do notbreed in the eastern part of the State. Even there they are common,however, in the fall, when they join the other swallows in coursingover the cotton fields. They fly very swiftly, often just above thetops of the plants, and many a boll weevil falls a prey to their per- 14 RELATION OF BIRDS TO COTTON BOLL WEEVIL. sistent hunting. Fourteen specimens were examined in September,of which 5 contained boll weevils. The total number of weevils con-sumed by the 5 birds was 52 and the largest number found in onestomach 23. Bank swallow.—These swallows, the smallest of the family, are
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Keywords: ., bookauthorhowe, bookcentury1900, bookdecade1900, booksubjectbirds
