398 ANNUAL EEPORT SMITHSONIAN INSTITUTION, 193 3 



that in the case of most tick-borne diseases the disease organism 

 passes a portion of its developmental stage in the body of the tick, 

 and hence the tick is the usual, if not the only, means by which the 

 disease is spread. 



THE FOWL TICK 



The fowl tick or blue bug, as it is popularly known, {Argas 

 ininiatus Koch) is one of the most persistent and serious pests of 

 poultry in the Southwest. It is widely spread in Texas, New Mexico, 

 Arizona, and California, and also occurs in destructive numbers in 

 Florida. Although the spirochaete disease which this tick carries 

 is not known to be present in the United States, the tick itself is so 

 insidious in its attack that it is much dreaded by poultry owners. 

 The facts that it can live more than 2 years without food and that 

 it is very hard to destroy with ordinary insecticides adds to its 

 seriousness as a poultry pest. 



This tick always provides for its next meal, keeping in close asso- 

 ciation with its hosts. After the first or seed tick stage it attacks 

 the poultry or birds at night and remains hidden in the cracks and 

 holes near their roosting places during the day. It attacks chickens, 

 turkeys, ducks, and other domestic fowls, and has been found on 

 vultures, quail, and certain other wild birds. Occasionally man is 

 bitten by it, especially when chickens are kept immediately adja- 

 cent to sleeping quarters. 



The seed ticks immediately after hatching from the eggs are 

 rather active and crawl about at night to seek a host. They attach 

 on various parts of the body, and require from 4 to 8 days to be- 

 come engorged. In 4 to 10 days they molt their skins and gain 

 a fourth pair of legs. These nymphs, as they are called, feed 

 but a few hours and hide in cracks or under bark, where they 

 again molt. After a third or fourth engorgement they molt to adults. 

 The adult ticks also feed for only short periods, after each of which 

 the females lay from 100 to 250 eggs in the cracks in which they are 

 hidden. (See pi. 2, fig. 1.) Females lay 4 to 7 successive batches 

 of eggs, each preceded by a blood meal. The eggs hatch in 10 days 

 during warm weather. 



The methods of combatting the pest are based on its life history. 

 They consist in making all fowls roost on perches which are so 

 arranged as to be easily examined and treated (pi. 2, fig. 2). Nests 

 are constructed which are readily accessible for treatment. The treat- 

 ment consists of painting or spraying the roosts and nests or the 

 entire inside of the chicken house, if it is generally infested, with 

 the wood preserver known as anthracene oil or with crude petroleum. 

 The introduction of the pests into uninfested houses can be avoided 

 by proper quarantine methods. 



