January 2006 Recently one of our club’s avid photographers was telling me of his adventures in capturing the image of a dragonfly. He told of moving around the pond as he followed the dragonfly from perch to perch. Each time that he was ready to snap the picture the darn darner flew away! After chasing the elusive creature around for a while he realized he was right back where he started! He set up his camera and captured the image of the dragonfly next time round. What our photographer observed is the territorial behaviour of some dragonflies. They will patrol an area for food moving from one perch to another. Males also claim territories during mating season and they will defend their territory by chasing other males away. Dragonflies are becoming more popular because they are so beautiful but they are also fascinating to watch because of their interesting behaviours. You can tell the temperature of a dragonfly by its perching behaviour – their perching posture is often related to regulating their body temperature. A cool dragonfly will not be able to fly. In order to warm its flight muscles it will bask in the sun perched at an angle that maximizes the sun exposure. Some will engage in wing whirring – a rapid beating of the wings – to generate heat. A hot dragonfly will perch with its abdomen almost straight in the air to minimize exposure to the sun – this is called obelisking. Or it may just perch in the shade or actually take a dunk in the water! Of course mating behaviour is always interesting and the dragonflies will not disappoint. You may have seen two dragonflies flying together like a truck and trailer. In these tandem pairs the male uses special claspers on the end of his abdomen to hold the female just behind her eyes. When they are mating the pair remains in tandem and the female brings the tip of her abdomen to the male’s secondary sex organ forming a heart of wheel shape. Some species mate in flight taking only a few seconds while others settle on a perch and take 5-10 minutes. A less often observed and studied behaviour is that of migration. In North America there are 16 species from the darner and skimmer families that are known to migrate. As the study is still young the destinations are still unknown as is much of the phenomenon. Birdwatchers, especially hawk watchers, have been helpful in reporting groups of migrating dragonflies. Groups of dragonflies are often seen advancing a weather front with the hawks. Time spent watching dragonflies will never disappoint. Last spring I was amazed by a dragonfly on the river in Florida. A Dragonhunter, a large clubtail dragonfly, captured and ate a Tiger Swallowtail butterfly on the wing! Now that was a sight! November 2005 I recently attended the Annual Conference of the Entomological Society of Ontario. As with any gathering of professionals there were the updates of ongoing projects and research, the peeks at new research and the reports on new products and applications. Usually there is at least one presentation that captures the imaginations of all and we were not disappointed this time. The report on Forensic Entomology with its gory pictures had us on the edge of our seats but it was upstaged by the feats of a tiny wasp! A trained wasp at that! Imagine training a creature that is the size of a pin head and only lives for a few days! And to what avail? When I returned home and reported to my husband of tiny trained wasps, he thought I was teasing him. He has been amused by the recent Dairy Queen TV commercial featuring a scientist who has learned to speak bee! Just like the second scientist in the commercial my husband asked "What possible scientific purpose could that serve?" Unlike the commercial the wasps have not been trained to attack on command. They are being used as bio-indicators. These wasps have been trained to detect the presence of the fungus that is responsible for the production of dangerous aflotoxins in peanuts. Obviously not a major Ontario problem, this project was presented by an African post-doctoral student working at the University of Georgia. How do you train a wasp? Well, it is not much different than Pavlov's dogs - you keep them hungry and reward with food. All the wasps trained were females - not because of some gender based intelligence quota - because females are able to detect the scent of a host from great distances. These wasps are parasites, laying their eggs in other tiny insects which they locate in a large field. Scientist thought that organisms that can detect such low levels of chemical could be very useful in detecting other chemicals. Hungry female wasps were allowed to feed on a drop of sugar water while being exposed to the scent of the fungus. Like Pavlov's dog they connect the scent with the reward of food. Three training sessions of 10 seconds each yielded the best trained wasps. A couple of days later when the wasps were hungry again they were taken to the field to find the fungus on the peanut plants. It is not quite like taking a dog out to hunt - you would never find the wasp again if you released it. The wasps are put into sealed cylinders with an open tube at one end. This is attached to a little machine that sucks in the scent of the plants. If the scent of the fungus is sucked into the cylinder the wasp will enter the tube to find food. When it enters the tube it sets off a trigger that indicates the presence of the fungus. These wasps could be trained to detect other diseases, too. Future work is being done on wasps detecting other chemicals such as explosives or drugs. Who knows, these wasps might be the next new employees at the airport security. January 2005 My husband and I were fortunate enough to spend Xmas in the subtropics of central Florida; a land where herons, ibis, egrets, woodstorks and alligators abound. Our frequent kayak trips on the local river afforded us many views of all of these big and exotic creatures, but what excited me the most was the sight of my favourite bug as we launched our boats on our first trip. Right in the docking bay were two large groups of whirligig beetles shimmering in the sunlight, more exhilarating to me than the 7 foot alligator that was guarding the opposite bank! The clattering of their shells as they bumped into each other in their frenzy to move away from my hull, was a welcoming serenade. Just beyond the first river bend, two yellow and black Zebra Longwing butterflies flew by us just under the tree where a couple of Woodstork were perching. Many Queen butterflies flew majestically from aster to aster along the riverbank. And the Queen's mimic, the Viceroy butterfly, was seen mating in the knapweed oblivious to the large group of vultures roosting in the Bald Cypress trees. They did not seem at all shy when the Tiger Swallowtail butterfly landed to bask in the sun beside them. While my eyes are scanning the riverbanks, water plants and the trees for birds, snakes, otters and alligators my entomologist's shorter focal length unconsciously is scanning for signs of six legs. While seeing new insects is wonderful, spottings of familiar insects like Praying Mantis and grasshoppers are always a thrill, too. The diverse range of some insects is amazing. I will never tire of our trips on the river with its alligators, birds, and wee creatures.

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