ECONOMIC ZOOLOGY ENTOMOLOGY. 251 



land plover, Eskimo curlew, etc. While excessive shooting, due to inadequate 

 state laws, has resulted in their recent decrease in numbers, it is thought that 

 with the wise administration of a federal law they will again become common 

 enough to afford the hunter a fair amount of legitimate siiort. 



Eleven important wild duck foods, W. L. McAtee ( U. S. Dcpt. Agr. Bui. 205 

 {1915), pp. 25, figs. 23).— In this bulletin, the third of a series on the subject 

 (E. S. R., 30, p. 545), the author shows how eleven groups of plants may be 

 successfully used as food for wild ducks in localities where now unknown. 



Those here described are musk grasses, duckweeds, frogbit (Limnobmm 

 spnngia), thalia (Thalia divaricata), water elm (Planera aquatica), swamp 

 privet (Forcstiera acuminata), eel grass (Zostcra marina), wigeon-grass (Rvp- 

 pia maritima), water cress (Si.sj/nibmim nasturtium-aquaticum) , water weed, 

 and coontail {CcratoplnjUnm dcnicr.sam). 



Mortality among- waterfowl around Great Salt Lake, Utah, A. Wetmore 

 (U. S. Dcpt. Agr. Bui. 211 (1915), pp. 10, pis. 3).— This is a report of progress 

 in investigations carried on by the Biological Survey in Utah and California 

 with a view to determining the cause and means for preventing the extremely 

 high mortality among ducks and other waterfowl. It is shown that untold 

 thousands of wild ducks, snipe, sandpipers, and other birds of less economic 

 value which frequent the marshes along the eastern shore of Great Salt Lake 

 and other localities, as Tulare and Owens lakes, California, perish annually. 

 During the work in Utah in 1914, 27 species of birds of 11 families were found 

 to be affected. "Among these were 9 species of ducks, 10 of shore birds, and 8 

 miscellaneous forms ranging from grebes and snowy herons to the pipit. 

 Among ducks the pin-tail and green-winged teal seenied to be most susceptible, 

 while the mallard, spoonbill, and cinnamon teal followed them closely. Avocets 

 and stilts suffered more heavily than any other shore birds. 



" The birds affected first lose the power of flight and are unable to rise in the 

 air, though in some cases they can flutter across the water and in others can 

 fly for a few rods before dropping back. The legs next become affected and the 

 power of diving is lost. As the birds grow weaker they crawl out on the mud 

 bars, if able to do so, or hide in growths of grass or rushes. In a later stage 

 of the affection they ard unable to rise. Finally the neck relaxes and the head 

 lies prostrate. If in the water death comes by drowning, but on land birds may 

 live for two days or more in this condition. 



"A large series of post-mortem examinations revealed no pathological lesions 

 other than that the intestine was reddened and firm and hard to the touch. 

 When the gut was slit, washed, and examined under a low magnification, the 

 capillaries in the intestinal villi were found to be distended, showing intense 

 irritation. ... A severe dysentery occasioned by the irritation of the intestine 

 was the obvious external symptom." 



Reference is made to the numerous theories that have been advanced to 

 account for the mortality, including bacterial infection, parasitic nematodes, 

 smelter and factory waste, etc., all of which appear to have been eliminated as 

 the probable cause. Pathological investigations of affected birds, a brief report 

 of which by J. R. Mohler, of the Bureau of Animal Industry of this Department, 

 is presented, have led to the conclusion that the affection is probably an acute 

 poisoning and not of bacterial origin. The author states that the work of the 

 past summer has led him to conclude that the mortality results from an alkaline 

 poison the nature of which is still to be determined. The absence of lesions in 

 any of the organs, other than a severe irritation in the lumen of the intestine, 

 the fact that practically all the affected birds are fat,- that a large percentage of 

 the birds recover when given fresh water, etc., all point to this conclusion. It is 



