Dragonflies hunting in the garden

I also saw lots of dragonflies in the garden this summer. They darted around displaying their aerial grace and agility as they hunted. I did manage to take a few photos of them while they briefly perched to watch for prey.

Life cycle

In all their life stages, dragonflies are voracious predators. Their larvae grow in water where they eat mosquito larvae and other aquatic creatures, such as tadpoles and small fish. Loss of wetlands, and pesticide spraying to control mosquitoes, threatens dragonfly populations.

At first, I thought the dragonflies were visiting out yard to lay eggs in the pond. Since the water circulates from the pond to the stream, it actually moves too much for either mosquitoes or dragonflies to lay eggs there. Instead, there were here to hunt. Now that we’re providing habitat for so many insects, there’s more food for dining dragonflies.

Adult dragonflies live for only a few weeks. They’re easy to recognize with their long-thin bodies and unique flight patterns. They have huge eyes that give them almost-360 degree vision. They can also detect the slightest movements of their prey or predators.

Their wings are their most amazing feature. They have two sets of transparent wings, and each one can move independently up or down, or can rotate like propellers. As a result, they can hover, turn, and dart in any direction to catch prey in mid-air. These strong fliers can reach 30 miles per hour.

Typically, they eat insects much smaller than they are, such as flies, leafhoppers, and beetles. They do sometimes catch larger meals, like other dragonflies and butterflies. Once they catch a meal, they rip it apart with their strong, toothed jaws.

For more interesting facts about dragonflies, visit the Mother Nature Network page 7 things you never knew about dragonflies, as well as the Ontario Parks page 10 cool facts about dragonflies.

Beautiful and diverse

Dragonflies are colourful, beautiful creatures. Once I examined my close-up photos, I realized that the dragonflies were all different; the colours and patterns on their bodies varied, and one even had patterned wings.

Migration

While dragonflies have been observed and tracked at their aquatic breeding sites, less is known about their movement and dispersal beyond their first home. Common Green Darners are well-known as long-distance migrants, like birds and Monarch butterflies. For them, one generation flies south in the fall where they breed, and then their offspring fly north in spring to breed again. (Dragonflies and Damselflies of the East, by Dennis Paulson, p. 13) So many dragonflies are migrating right now that they’re showing up on weather radar. (CTV news article)