AVIAN BOTULISM—ANOTHER PERSPECTIVE
Waterfowl botulism is unique among intoxications because toxin produced within its victims leads to secondary poisoning of other birds. Because of this phenomenon, the epizootiology of the carcass-maggot cycle of botulism resembles that of an infectious disease and the reproductive rate (R) of the disease could be defined as the average number of secondary intoxications attributable to a single carcass introduced into a marsh. I propose that toxin production and botulism occur commonly at a low level in many marshes and that factors which influence R determine when the disease expands into a large epizootic. A model that incorporates the number of carcasses occurring in a marsh, the probability of a carcass containing spores, the probability of a carcass persisting until toxin-bearing maggots emerge, and the contact rate between live birds and toxin, may be useful for predicting the extent of secondary-poisoning, for identifying questions for research, and as a theoretical basis for management.
The role of avian carcasses in botulism epizootics
KAMINSKI, R. M., AND H. H. PRINCE. 1981. Dabbling duck and aquatic macroinvertebrate responses to manipulated wetland habitat. J. Wildl. Manage. 45:1-15. KRULL, J. N. 1970. Aquatic plant macroinvertebrate associations and waterfowl. J. Wildl. Manage. 34: 707-718. LEITCH, W. G. 1964. Water. Pages 273-281 in J. P. Linduska, ed. Waterfowl tomorrow. U.S. Dep. Inter., Washington, D.C. McNIcoL, D. K., B. E. BENDELL, AND R. K. Ross. 1987. Studies of the effects of acidification on aquatic wildlife in Ontario. Can. Wildl. Serv. Occas. Pap. 62. 76pp.
Statistical analysis of survival data.

 A general review of the statistical techniques that the authors feel are most important in the analysis of survival data is presented. The emphasis is on the study of the duration of time between any two events as applied to people and on the nonparametric and semiparametric models most often used in these settings. The unifying concept is the hazard function, variously known as the risk, the force of mortality, or the force of transition.
