1923 ENTOMOLOGICAL SOCIETY. 47 



THE FEATHER MITE— A NEW PEST OF POULTRY 

 L. Caesar, Ontario Agricultural College, Guelph 



The presence of a new mite {Liponyssus bursa) in this province was brought 

 to my attention by Mr. F. C. Bishopp, of the U.S. Bureau of Entomology, 

 last December at the annual meeting in Toronto, when he informed me that 

 he has seen birds badly infested with the mite which had been shipped into the 

 United States by a certain Ontario poultryman. At once I wrote to this man, 

 informed him of what I had been told, and urged upon him the prompt applica- 

 tion of effective control measures as outlined in Circular 79 of the United States 

 Department of Agriculture, of which Mr. Bishopp had given me a copy. Then 

 as soon as my college work permitted I visited his plant and inspected a large 

 number of his birds, but found only one mite, and that one on a feather in a 

 nest. The owner, however, informed me that the birds in one section of his 

 plant had been infested, but that by thorough applications of zenoleum he had, 

 he believed, exterminated the mites. He certainly had at least come very near 

 doing so. 



By this poultryman I was given the address of another man, about fifty 

 miles away, who was having trouble with the same mite. This poultryman was 

 then visited, and the mites were found in one of his houses, but as treatment 

 had been carried on here too the birds were not badly infested, though the owner 

 and his wife both said that a few weeks earlier the mites had been abundant 

 in this particular house. 



I endeavoured to find the origin of the infestation. The first poultryman 

 said he had got the mites from birds shipped in from the Southern States, but 

 Mr. Bishopp was of the opinion that this must be a mistake. The other poultry- 

 man thought he got his from exhibiting at a poultry show in one of our cities. 



I have not since had any complaints of trouble in other flocks, but would 

 not be surprised if it should turn out that the mite was somewhat widely spread 

 both in Canada and the United States. 



All the adult mites seen were blackish in colour with some white areas, 

 chiefly around the head. Some of the young were blackish like the adults, others 

 were nearly white. The adults look to the naked eye like mere black specks, 

 and, as one of the poultrymen said, when on a bright winter day they cluster 

 upon the tail feathers of a white bird to bask in the sunshine, they make the 

 feathers appear as if dusted with black pepper. 



Unlike the common red mite (Dermanyssus gallinae De Geer), which attacks 

 poultry only at night, hiding in crevices in roosts and in other places by day, 

 this species usually remains both night and day upon its host. They can be 

 found most easily in the feathers around the vent, but may occur almost any- 

 where among the feathers. Some of them, however, may also be found in the 

 nest on feathers and other substances. 



The eggs are oval, and glossy white, and, so far as observed, were situated 

 in the feathers near the base where they could easily be dislodged by tapping 

 the feathers. 



The mites are able to endure a great deal of cold, as I discovered by placing 

 several feathers with mites on them in a bottle and exposing this overnight 

 to a temperature which reached 7° F. Next day, after carrying the bottle in 

 my pocket for a couple of hours, I examined it and found almost all the mites 

 alive and quite active. These same mites were kept in this bottle for 18 days 

 before they all died. These facts show that the pest might easily be transported 



