5 Populations and Communities Imagine that a developer is proposing a new subdivision in your Northern California planning district and that there are rumors that red-legged frogs, which are listed under the . Endangered Species Act (ESA), live on part of the proposed development site. | 5 Populations and Communities Imagine that a developer is proposing a new subdivision in your Northern California planning district and that there are rumors that red-legged frogs Rana aurora which are listed under the . Endangered Species Act ESA live on part of the proposed development site. The developer is aware of this issue and wants to do the right thing legally and ecologically so together you decide to look for ecological expertise in planning around the frog. You begin with A Field Guide to Western Reptiles and Amphibians a standard if basic field resource. The guide s range map for the red-legged frog shows this species occupying a continuous band along most of the . West Coast including your region see Figure 5-1 . Although it appears from the map that one can find this frog the largest native frog of the western United States anywhere along the coastal zone the accompanying text says that the species frequents marshes streams lakes reservoirs ponds and other usually permanent sources of water. When not breeding may be found in a variety of upland habitats. 1 The range map is generally correct in depicting where the frog lives it does not live in Arizona or Idaho but it is at the wrong scale to help you address the issue at hand how to plan a subdivision to protect the frogs. To answer this question you will need a deeper understanding of the frog s ecology. In this chapter we present key principles that describe the ecology of populations and communities of organisms. These concepts are especially useful for planners designers and developers working on a variety of questions including the following Populations and Communities 73 Northern Red-legged Frog H California Red-legged Frog Figure 5-1. This range map indicates that redlegged frogs inhabit Northern California but planners and designers would need more information to know whether they live on a particular site and whether the threatened California subspecies in particular lives on the site.
