Abundance of a few SGCN has always been low and conservation actions are not likely to increase population size to a secure level. Three characteristics on which rarity can be based are geographic range, habitat specificity, and local population size (Rabinowitz 1981). Rare species are much more likely to experience declines and have a higher potential for being extirpated in Michigan.

The Peregrine Falcon is an example of a species with a wide geographic distribution, narrow habitat specificity, and small local population size. Preferred habitat for Peregrine Falcons in Michigan was historically limited to rocky shorelines and rock outcrops in the Upper Peninsula. Current distribution reflects the ability of peregrines to adapt to human structures that mimic natural habitat. Eleven of the 16 identified areas currently used by peregrines are found either on buildings, bridges, or artificial platforms on smokestacks in southern Michigan. Due to the limited amount of habitat, peregrines will never be abundant in the State.

As an endemic species, Hungerford's crawling water beetle possesses a small geographic range (extending through parts of the northern Lower Peninsula and Ontario) and narrow habitat specificity (adults are generally found in portions of cooler stream segments that have riffles and stronger currents), and demonstrates a scattered, small local population. USFWS listed this species as federally endangered, in part, because of its rarity and threats associated with its habitat (USFWS 1994). Rare species are typically legally protected with either endangered or threatened species status.

Conservation Needs to Address Rarity Issues:

Land, Water & Species Management

• Develop management plans for rare species that ensure maintenance of viable population levels

Research, Surveys & Monitoring

• Identify historically rare species and develop habitat suitability models
  
  
• Determine population levels that will ensure viability and protect species in their habitats
  
  
• Develop monitoring protocols for rare species