18 BULLETIN 862, U. S. DEPARTMENT OF AGRICULTURE. 



account of the fact that the birds have little suspicion of man and 

 fly in compact flocks, affording opportunities for pot shots, the green- 

 winged teal has been greatly reduced in numbers. It is one of our 

 most desirable game birds and should be carefully guarded against 



further depletion. 



Vegetable Food. 



Of the contents of 653 8 green-winged teal stomachs examined, 

 more than nine-tenths (90.67 per cent) consisted of vegetable matter. 

 By far the largest item of food contributed by any one family of 

 plants came from the sedges, and this amounted to nearty two-fifths 

 (38.82 per cent) of the total food. Next to the sedges, pondweeds 

 are the favorite food supply, contributing 11.52 per cent, while 

 grasses follow closely with 11, then smartweeds 5.25, algae 4.63, 

 duckweeds 1.9, water milfoils 1.11, arrow-grass 0.91, and bur reed 

 0.85 per cent. The remaining 14.68 per cent is made up of a great 

 number of smaller items. 



SEDGES (CYPERACEAE), 38.82 PER CENT. 



The sedges form a very constant item of food for the green-winged 

 teal, being found in some form in 530 of 653 stomachs and forming the 

 sole content of 51. Usually the seeds are taken, but practically all 

 parts of the plants are eaten when } T oung and tender. Seeds of bul- 

 rushes (Scirpus spp.) form the largest item among the sedges, being 

 found in the greatest number of stomachs and represented by several 

 species. Unidentified bulrush seeds were found in 205 stomachs. 

 The most commonly identified species was three-square (Scirpus 

 americanus) from 121 stomachs. Seeds of prairie bulrush {Scirpus 

 paludosus) were found in 46 stomachs, those of salt-marsh bulrush 

 (Scirpus robustus) in 40, Scirpus cubensis in 13, and river bulrush 

 (Scirpus jluviatilis) in 5. Other genera of sedges represented were 

 Fimbristylis, found in 90 stomachs, Carex in 72, Cyperus 48, spike 

 rush (Eleocharis) 45, beaked rushes (Rhynchospora) 5, saw grass 

 (Cladium) 91, and unidentified sedge seeds in 44. No fewer than 

 30,000 seeds of a Cyperus were found in one stomach and 25,000 in 

 another, while Eleocharis and Fimbristylis seeds also occasionally 

 reached as high as 1 ,000 per stomach. 



PONDWEEDS I NAIADACEAE). 11.52 PER CKNT. 



The pondweed group includes the true pondweeds (Potamogeton 

 spp.), ditch or widgeon grass (Ruppia maritima), horned pondweed 

 (ZannicheUia jxilustris), eelgrass (Zostera marina), and bushy pond- 

 weed (Najas spp.), all of which were found in stomachs of the 

 green-winged teal, and seem to form a very important element of 

 their diet. In most cases the seeds alone are taken, but the ducks 



8 Two hundred and sixteen of these were examined by W. L. McAtee. 



