inventories can detect trends but will do little to determine causality or 

 help generate predictive hypotheses (Palmer 1987). Long-term conservation 

 requires a knowledge of many life history parameters including fecundity, 

 recruitment, survivorship, age structure, and population flux. Demographic 

 monitoring techniques can provide information on factors regulating population 

 density and persistence (Palmer 1987). This information, in turn, provides an 

 essential basis for management decisions. 



Arabis fecunda is a candidate for listing as a threatened or endangered 

 species by the U.S. Fish and Wildlife Service (USDI-FWS 1993), is considered 

 sensitive in Region One of the U.S. Forest Service, and is considered 

 threatened in Montana (Lesica and Shelly 1991). Little is known about the 

 life history and demography of Arabis fecunda populations. The purpose of 

 this study is to determine demographic patterns and variability for this rare 

 species and to use this knowledge to recommend appropriate management 

 strategies for conservation. 



METHODS 

 The Species 



Arabis fecunda Rollins is a rosette-forming, perennial in the Mustard 

 Family (Brassicaceae) . This recently described species (Rollins 1984) is 

 endemic to highly calcareous soils in the foothills of the Sapphire Range in 

 Ravalli County and in the Pioneer Range in Beaverhead and Silver Bow counties 

 in southwest Montana. Arabis fecunda plants flower in April and May, and 

 fruits mature in June and July. Flowering occurs in one of two ways: (1) 

 axillary flowering - 1 to many decumbent inflorescence stems develop from 

 axillary buds among the tightly clustered leaves of the rosette or (2) bolting 

 - a single inflorescence stem is produced from the terminal bud in the center 

 of the rosette. Bolting inflorescences are generally larger and leafier than 

 axillary inflorescences. An individual rosette may produce axillary 

 inflorescences for numerous years, while bolting rosettes always die. Some 



