Step 1:  Find the habitat for a particular species of butterfly. 

The key to finding caterpillars is first understanding the habitat for the adult butterfly.  There are many types of butterfly habitat.  The common element to these habitats usually is the availability of plants that feed both the adult butterflies as well as their caterpillars.  More.

Step 2: Identify the species of butterfly.

This can be done either by capturing the butterfly, recognizing it, or taking a picture of it. There are many online resources that can help you quickly identify buttefly species by color pattern.  More.

Step 3: Identify the species of plant(s) caterpillars of this butterfly use in your habitat.

Now that you know the species of butterfly, you have several resources you can research to learn what species of plants--termed larval host plants--you need to check out to find caterpillars.  The Host Plant Identification section arranges documented larval hostplants as associated to butterfly familes.  Another great resource is Butterflies of America. 

Step 4: Return to your habitat and look for eggs or caterpillars on their larval host plant.

Once you've identified the species of larval host plant associated with your butterfly, return to the habitat and search for this plant.  Next, look for eggs or caterpillars either on the leaves or flowers.  There is an encyclopedia of knowledge with regards to understanding helpful hints to help you find  caterpillars of specific butterflies on their respective host plants.  More.

Step 5: Return to your habitat to collect live females to set up for laying eggs in the lab.

If you're having a hard time finding butterfly eggs or caterpillars on their larval hostplants for whatever reason, consider collecting and caging live females to get them to lay eggs.   More.

 Mountain Canyon Habitat

Colorado Hairstreak--Hypaurotis crysalus citima

Scrub Oak--Quercus gambellii

Colorado Hairstreak ovum