dragonfly species recorded the dragonflies & damselflies ... › pdfs ›...
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onfly speciesthe Churchi
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SBN 978-0-968012
s recorded ill Region Lake Darner Sedge Darner Azure Darner Zigzag Darner Boreal Snaketail dsonian Whiteface
American Emerald Ringed Emerald Delicate Emerald
Hudsonian Emerald Muskeg Emerald tehouse’s Emerald
s recorded ill Region Subarctic Bluet Taiga Bluet Boreal Bluet
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Figure 6 . Zigzag Darner (Aeshna sitchensis)
Figure 7 . Hud(Leucorrhinia
© B. Nikula
Figure 5 . LaDarner (Aeseremita)
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Figure 8. Ringed Emerald (Somatochloralbicincta)
Figure 10resolutum
© B. Nikula
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© B. Nikula
© B. Nikula
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The Dragonflies & Damselflies of the Churchill
Region
The dragonflies and damselflies (order Odonata) are an ancient group of very efficient predatory insects. They were among the first animals to have powered flight, and even today few can match their speed and manoeuvrability in the air. There are an estimated 6000+ species of dragonflies worldwide, but in the Churchill region only 15 species have been recorded. While it is certainly possible that others will be found in the region, this guide lists only those species with confirmed records.
Description
As adults, both dragonflies and damselflies are daytime hunters, using their large eyes and aerobatic skill to capture small flying insects. Dragonflies tend to be larger and stouter, and hold their wings parallel to their perch when at rest. Damselflies are more delicate, and fold their wings vertically over the back when not in use. Odonates are fearsome predators, capturing flying insects on the wing with their specialized basket-like arrangement of legs. We hope that this pamphlet provides a useful and informative introduction to the fascinating world of dragonflies and damselflies.
Life Cycle
and bluets, are active hunters, climbing through submerged vegetation and litter in pursuit of smaller invertebrates. In their later stages, some are large enough to take tadpoles and small fish! Others are ambush predators, lying quietly buried in mud and sand at the bottom of their pond with only their eyes and respiratory structures in contact with the water. Many have hairs that trap silt and muck to improve their camouflage. When a prey-sized animal passes, they are quickly captured by the hinged lower lip (Figure 4, red arrow), unique to Odonata, that can snap out at incredible speeds to grasp the prey and bring it to the mouth. Only within the past few years has filming equipment been developed with a high enough frame rate to capture this remarkable motion.
Life Cycle
Dragonflies and damselflies spend the greatest part of their lives in the larval stage, and this is particularly true in the cold north. Lower temperatures mean slower development, and in the high arctic larger species must spend up to 10 years as larvae before they can emerge and fly. Because of this long aquatic stage, they require bodies of water sufficiently deep that they do not freeze to the bottom for successful development (Figure 2).
Dragonfly larvae are heavily-built with only short spikes (Figure 3, top) on the hind end, while damselfly larvae are more slender, with large, leaf-like gills (Figure 3, bottom). Most are found in ponds and lakes, although there are many species that are adapted to flowing water habitats. Some of these larvae, such as the darners
© S.A. Marshall
© S.A. Marshall
Figure 2. Species-rich habitat west of Twin Lakes, near Churchill.
Figure 3 . Larvae of Odonata Figure 4 . Larva of Aeshnidae
Figure 1. Mating pair of Boreal Bluets (Enallagma boreale). The male is blue, and the female is brown.
© S.A. Marshall
© T.S. Woodcock