Tuesday, May 29, 2012

Review: Peterson Field Guide to Moths of Northeastern North America

A long-awaited update to Charles Covell's Moths of Eastern North America is finally in print this spring. Moths are among the most diverse insect groups – over 11,000 species have been catalogued in North America alone. They also play an important role in ecosystems, as pollinators for many plants and as food for birds, bats, and other animals. Yet their nocturnal habits and poor reputation as pests keeps them from being better appreciated. In fact, very little is known about many moth species – in some cases even basic information like their range or larval hosts. Among more popular groups like birds and butterflies, this sort of information is often collected by amateur observers, who supplement the work of scientists. David Beadle and Seabrooke Leckie hope to encourage a new generation of moth observers with their new guide, the Peterson Field Guide to Moths of Northeastern North America.

The new guide covers nearly 1,500 moths found in the northeast, roughly from Minnesota and Missouri east to Virginia and the maritime provinces. Of these, about two-thirds to three-quarters are macromoths, and the rest are micromoths. These 1,500 moths are the ones most likely to be encountered, especially at a light trap or sugar bait. The increased coverage of micromoths compared to existing guides is especially welcome. At my UV light, I see far more micromoths than macromoths, and it usually takes me a long time to identify them. One moth I was surprised to see omitted is the Indian-meal Moth – the moth most likely to infest a pantry – which has a very distinctive adult form.

The new guide uses the format familiar from other recent Peterson guides: plates on the right page and descriptive text on the facing page. The text includes the Hodges number (and MPG number for noctuoids), size, a succinct description, host plants (if known), and range. The species accounts include a range map for most macromoths but not for micromoths, which I believe is a first among moth guides. Unfortunately sufficient data does not exist to produce a range map for many species. The accounts also include a tricolored bar to indicate approximate flight periods. When I first flipped through the guide, the bar's meaning was not obvious to me, but it is explained in the introduction. The guide is illustrated with photographs that have been digitally edited to remove the moths from their backgrounds. Many of the photos are by the authors, but they also drew on other photographers to supply images. The photographs are of excellent quality, and the color is true to life, as far as I can see. The plates show the moths as they appear in life rather than as mounted specimens, which is a major improvement over Covell's guide for identifying moths in the wild or at light traps.

I sense some possible influence from Kenn Kaufman's excellent series of field guides here, and not only in the use of digitally-edited photographs. One feature of Kaufman's butterfly and insect guides that I really like is the inclusion of a silhouette showing the actual size of one species on each page, with the all the species on the same page scaled relative to that species. This feature helps especially with identifying very small insects such as micromoths. It helps to have a visual sense of how small they are but also have the illustrations large enough to see the detailed markings on the wings.

The new Peterson Field Guide to Moths of Northeastern North America is the best English-language* resource currently in print for the region it covers. If you are interested in identifying moths in northeastern North America, this is the book to use. (Moths of Western North America is available for that region.) Since obtaining a copy, I have already used it to identify several moths. I must say that having a book in my hand makes a huge difference when I am trying to find a familiar-looking but unknown moth. It is much faster (and less strain for my laptop) than browsing through the plates at the Moth Photographers Group (though that website is excellent). It should make identifying moths at my UV light and active participation in projects like National Moth Week much easier.

This review is based on a copy provided by the publisher. I have corresponded with one of the authors, Seabrooke Leckie, for help with moth identifications on a few occasions.

I have not seen a copy of Louis Handfield's French-language Guide des Papillons du Québec (published by Broquet) to do a proper comparison between the two guides.