A word about butterfly conservation:
The most important thing you can do with butterflies is to help preserve their wonderful diversity...The main threat facing butterfly populations is loss of habitat. Some of our most beautiful butterflies, such as the Regal Fritillary and the Hermes Copper, have disappeared from much of their former range because their specific habitats have been destroyed. Preserves for butterflies do not have to be very large, but without them we will certainly lose some species.
Pollution of their surroundings, especially with insecticides, poses another problem. Widespread, indiscriminate spraying for gypsy moths has undoubtedly killed billions of butterflies, along with countless numbers of our beautiful silk moths and others. Several butterflies in southern Florida have become quite rare in recent years, and we have to wonder whether heavy, continuous spraying for mosquitoes may have been a factor.
Uninformed persons sometimes imagine that butterfly collectors pose a threat also, but there is scant evidence for this. During an average week in summer there are probably more butterflies killed by cars on American roads than the total taken by all the collectors in history. For any would-be protectors of butterflies, harassment of net-wielding lepidopterists is a waste of time; habitat protection is a more worthwhile effort.
Two conservation groups especially deserve support:
The Xerces Society
The Nature Conservancy
from Jim Brock & Kenn Kaufman's Butterflies of North America - Kaufman Focus Guides, p. 17, Houghton Mifflin 2003.