Feeding Behavior and Food 



FEEDING BEHAVIOR 



The Swainson's Warbler is primarily a ground feeder, but it 

 sometimes searches for food a few feet above the ground in 

 undergrowth. It also forages along the top sides of logs that are 

 lying on the ground, and it may fly to the side of a tree trunk to 

 pick off an insect that is a foot or so from the ground. Sometimes 

 it reaches or hops up a few inches from the ground to take insects 

 from the undersides of leaves of low-growing herbaceous plants, 

 and occasionally it flies from perches in the lower parts of trees 

 in pursuit of insects. Large insects are held in the end of the 

 bird's bill and beaten against the ground until broken into several 

 pieces. 



The Swainson's Warbler searches for food in a manner different 

 from that of other ground-feeding parulids that I have observed. 

 Insects are located mainly as the bird pokes its bill under leaves 

 or piles of leaves, pushing them upward and searching the ground 

 beneath or examining the undersides of the leaves. A leaf may 

 be held up momentarily and tilted at an angle as the bird inspects 

 the underside. If part of a leaf is curled, the upper and the lower 

 mandible of the bird are parted to uncurl it. Sometimes, as the 

 bird moves hurriedly forward lifting and shoving leaves from side 

 to side, its entire body disappears beneath the leaves. Most of the 

 Swainson's Warblers that I collected in the course of their food 

 searching in the Ocmulgee River floodplain forest had their bills 

 caked with mud. 



The bill of the Swainson's Warbler is larger and sharper pointed 

 than the bills of the Ovenbird, the Louisiana Waterthrush, and 

 the Kentucky Warbler, ground-feeding parulids that in the gen- 

 erally level terrain of the southern floodplain forest obtain their 

 food primarily from the surface of the leaf litter. The Kentucky 

 Warbler works across the forest floor, often under a partial cover 

 of low herbaceous vegetation such as wood-nettle, jewelweed 

 (Impatiens sp.), or poison-ivy (Rhus Toxicodendron). It hops 

 along, flushing insects and picking them off stems and from be- 

 neath leaves of low-growing plants, and pokes its bill into piles 

 of leaves or sticks. The Ovenbird (a walker) feeds similarly, but 

 more in the open, as does the Louisiana Waterthrush (also a 



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