s 



577.82 

 Nlllec 

 2002 



rMM STATE 



3 0864 1001 8344 4 



[^ Natural Heritage 2002 List of Ecological 



Program Commnities for \Xontayna 



^i^ 



COLLECTION 



-ZOOi 



MONTANA STATE UBRARY 



1515 E. 6th AVE. 

 HELENA, MONTANA 59620 



FYqjared by: 



Montana Naniral Heritage Program 



Montana State Libran 



P.O. Box 201800 • 1515 East Sixth .Ave • Helena. MT 5%20-180O • 406-U4-3009 



http: nhp.nris.state.mt.us 



Introducrion 



What t>pes of natural vegetation exist across Montana's landscape? VMiere do diey occur and 

 why? Which communitv tvpes are intrinsically rare or limited in distribution, and which are 

 widespread? \Much have greatly diminished in extent and ma> be at risk? 



.Ajisw ers to these questions are important to gtiide resource management, however these answers 

 hinge on how we define and categorize the rich ecological diversit> that is among Montana's 

 greatest natural assets. Ecologists at the Montana Natural Heritage Program sy stematically 

 collect information to help identify and understand the natural communities of Montana. They 

 utilize a classification approach, developed in parmership with the network of Natural Heritage 

 Programs, diat is scientifically soimd, consistent and flexible. 



Nauiral commimities are assemblages of species that respond similarly to climatic, soil, 

 topographic, geological hydrologic. historical and other environmental conditions. . 

 Communities are identified primarih by unique repeating assemblages of plant spedss. But 

 commimities are more than the sum of their species - the> also represent the myriad biological 

 and en\iroimiental interactions that are inherently a part of each unique natural sysiem. Thus, 

 environmental characteristics, ecological processes and associated fauna are also used in 

 characterizing natural communities. .An underhing assumption is that vegetation is one of the 

 best indicators of en\ironmental characteristics. 



Natural communities have great value for resource management. It is now widely agreed that 

 managing biological resources on a species by species basis is impractical and inadequate, except 

 for a relatively limited number of large mammals, birds and plants that are of particular value to 

 people or in special cases where particular species are facing individual threats to their survival. 

 How ever there are many thousands of species that make up our native ecosy stems and pla\ a key 

 role in the health of those s> stems - soil development pollination, breaking down organic 

 materials into nutrients, and as links in the food chain. 



Communities are increasingly used as management units that represent certain "habitats" — 

 assemblages of species adapted to similar conditions and processes. Thus, armed with 

 knowledge about the diversity . composition distribution, status and ecological reqtiirements of 

 communities, managers can focus on these naturalK -occurring assemblages of organisms to 

 maintain the health of multitudes of species and interactions that would be impossible to manage 

 individually. 



MONTANA STATE LIBRARY 



