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Leo Parker
Leo Parker

Dragonflies Through Binoculars: A Field Guide T...


Common Whitetails are among the most abundant and widespread of our dragonflies, found throughout nearly all of the US and southernmost Canada and northernmost Mexico. Two reasons this species is so common are that they are strong, aggressive fliers, and their aquatic larvae are fairly tolerant of low oxygen in the water, and organic pollution. As suggested by the photo, adults are attracted to the brown color of mud. It's fun to watch this species darting about defending its territory of 20-180 square yards. When one Common Whitetail wishes to communicate to another that it should leave the territory or else, it raises its abdomen as a threat display. Males wishing to reply that they mean no harm and regard themselves as submissive, lower their abdomens.




Dragonflies through Binoculars: A Field Guide t...



Down through time dragonflies have been called a number of colorful names, such as snake doctors, Devil's darning needles and mosquito hawks. My mother called them Devil's darning needles. In fact, to this day, I vividly remember her telling me that if was naughty, a Devil's darning needle would sew up my lips.


In Poland, farmers are known to round up their poultry during dragonfly migrations. This is because some dragonflies are host to liver flukes that infect turkeys and chickens. The farmers think that poultry left in fields during dragonfly migrations are at great risk of liver fluke infections.


If you would like to become a dragonfly watcher, there are a things that will help you; namely, close-focusing binoculars, a digital camera and a field guide to dragonflies. Close-focusing binoculars enable you to focus on objects 6 or fewer feet away. In addition, a digital camera will allow you to take pictures of dragonflies you encounter. These photos will be of great help when you try to identify these winged predators at your leisure.


When finding birds becomes more a chore than a pleasure, as in early summer when trees are fully leafed out and the migration is largely over, many birders turn their attention to insects. Butterfly watching, of course, has long been popular. One of the early Peterson Field Guides (from 1951), for example, was Butterflies and Moths with hundreds of hand-colored drawings. The most recent comprehensive guides are the Butterflies through Binoculars series by Jeffrey Glassberg, two volumes, eastern and western, with photos and descriptions of all North American species. Dragonfly watching now has its own Dragonflies through Binoculars, including color photos, descriptions and range maps (but no keys) for all 307 species found in North America. A better choice for a field guide to local dragonflies, I think, is the Color Guide to the Common Dragonflies of Wisconsin, pocket-sized, with excellent photos, and treating most of the common species of northeastern Illinois.


All of the phenotypic data were collected from published field guides or reliable internet sources. The field guides are listed in Online-only Table 2. All the field guides have been published by respected odonatologists and experts on species identification. Our database is therefore not static, and additional data will be added as it becomes available. Researchers interested in contributing to this project are encouraged to contact the author for correspondence on how to incorporate new data. We will accept data both from already published sources (e. g. scientific papers) even if it has already been deposited in other databases such as Dryad, as well as data that is not intended to be published elsewhere, as long as it can be tailored to the format of the Odonate Phenotypic Database. Each species has a reference list, which lists the references from where the data were gathered, so it is possible to check each entry against these primary sources.


We would like to acknowledge the students and laboratory assistants that helped us to collect the data from the literature, and in particular Anna Kell, Ev Poslin, Hanna Bensch, Robin Pranter, Kajsa Svensson, Lisa Winberg, Karolina Pehrson, Mireia Balesta and Tammy Ho. We would like to also thank the many authors of the field guides from which our database references. Our database is by no means nor intends to be a substitute for these valuable books. Funding for this study have been provided by research grants from The Swedish Research Council (VR: grant no. 2016-03356), Gyllenstiernska Krapperupstiftelsen (grant no. KR2018-0038) and Olle Engqvist Byggmästares Stiftelse to E.I.S. and from a Faculty Mobility grant from the University of Costa Rica and a grant from the Schlumberger Foundation to B.W. Open access funding provided by Lund University.


Certain species, however, will have a preference for certain types of habitat. They are also not present all year as adults, but generally dragonfly and damselfly species appear by late April and continue to fly until October. You can find this information for selected species on this website or in field guides.


There are many fine field guides, but one might consider Dragonflies of the North Woods by Kurt Mead and Damselflies of the North Woods by Bob DuBois and Mike Reese. Both can be found in local bookstores or ordered online.


While these two field guides are designed to cover an area just to our north, there are very few dragonflies and damselflies within our area that won't be in these books. If you prefer buying just one of these books the Kurt Mead book not only has the dragonflies, but also a short introduction to the more common Minnesota damselflies as well.


Dragonflies, by definition, are stout and large bodied with round heads and eyes covering much of the top and sides of the head. The forewings and hind wings are different shapes and are held straight out to the sides while resting. They are strong fliers. Damselflies, on the other hand, are more delicate and small bodied. Their abdomens are narrow, their heads are wider than long and the eyes are separated by more than their own width. Distinctive from dragonflies, damselfly forewings and hindwings are similar in shape and held either pressed above the body or are only partially open at rest. For the most part, they are much weaker fliers. In New Jersey, the season for dragonflies and damselflies runs from April through October, although the best month for spotting the most species would be June. This coincides with the increasing photoperiod (length of daylight) and moderating temperatures.


These miniature predators actually start their life span as larvae and may spend one or more years under water! Once they surface, they go through a molt in the morning hours that leaves them vulnerable to other predators. Later in the day, their body parts and wings are dry, and they're ready to start their adult flying life. As adults, their life cycle is anywhere from several weeks to months. Food preferences range from insects, mosquitoes, butterflies and other dragonflies they are non-discriminatory on this point. Preparing for the next generation, the adults will lay their eggs on or in plant stems located in ponds and streams, or sometimes in the sediment. The best places to find dragonflies and damselflies are usually in clear, clean water; like a swiftly moving stream, a pond or lake. However, forested areas with associated stream complexes may offer up a smaller percentage of species. Another good location to watch them is in farm fields and open areas that have an abundance of insects.


So who is looking at dragonflies and damselflies? It appears that this is the "new birding". Many tried and true birders, in their quest for knowledge and new things to look at while enjoying the outdoors, have included butterflies and dragonflies on their "to do" list. Tom Halliwell, past president of the New Jersey chapter of NABA (North American Butterfly Association), became intrigued with dragonflies about five years ago after meeting and sharing lots of field time with odonate expert Allen Barlow. A long time birder turned butterflier, Tom became fascinated with these colorful, quick moving fliers. They presented "a new challenge" he says. "It seemed like a natural progression since I enjoy all aspects of the natural world. Their predatory behavior is extremely interesting." Other birders-turned-dragonfliers include George Nixon, who, under Tom's expertise, has become a serious student of Odonata. He has formed a group, JOE (for Jersey Odonate Enthusiasts) whose sole purpose is to conduct field trips in New Jersey to seek out all species of dragons and damsels. A major activity for JOE will be to conduct surveys within the Delaware Water Gap National Recreation Area and various NJ Nature Conservancy preserves. For educational material with species descriptions and photographs, flight periods and checklists, as well as upcoming field trips (in season) check their website.


Now that you're intrigued, how do you get started identifying dragonflies? Close focus binoculars are the first piece of equipment necessary. They should preferably focus down to 5 to 7 feet. A digital camera with close focus capability helps when referring back to species seen that day in the field. Next, a 10x loupe or magnifying glass is helpful in making distinctions between closely related species. There are now many field guides available, including the Stokes Guide to Dragonflies and Damselfies, Damselflies of the Northeast by Ed Lam and the Field Guide to Dragonflies and Damselflies of Massachusetts by Nikula, Loose and Burne (applicable for NJ) and Dragonflies Through Binoculars by Sid Dunkle.


Experts are leading field trips and teaching workshops, newsletters have appeared, Internet sites offer identification help and the first national field guide is scheduled for publication next spring.


In Shropshire there are only a few dragonflies that require close up examination in the hand for identification purposes. For this a x10 hand lens will be sufficient. To catch such specimens a round framed soft mesh net should be swept up and under from behind the insect to reduce the chance of any damage to the head area. Great care must be taken not to damage the insect and it is best to attend a field course or seek advice with regards to the correct handling of dragonflies and damselflies. Advice on netting can be found via this link to the British Dragonfly Society Code of Practice on collecting Dragonflies. This document also outlines the very rare circumstances in which the permanent collection of specimens is acceptable. This is not necessary for identification of Dragonfly specimens in Shropshire and with excellent close focus cameras now widely available the few difficult species can be briefly held and examined and the photographs sent for identification never the insect! It is also worth noting that certain species elsewhere in the UK such as the Norfolk Hawker are legally protected and as such require a licence for netting and handling. 041b061a72


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