This dragonfly completes its journey in three stages. The green darner dragonfly has one of the most studied migrations of any species of dragonfly. The insects can sometimes gather in great clouds or ribbons, particularly before crossing large bodies of water. Migration also occurs north, though larger groups of migrating dragonflies seem to be observed in the Autumn wave. In the US the migration tends to be during the Autumn with dragonflies heading from the North down to the South, usually in pursuit of warmer weather. Non-migratory remains in its habitat throughout the year Partial migration some individuals migrate, while others hibernate Species include those which are already resident in the UK, such as the migrant hawker, or others that are not usually found here, such as the lesser emperor. These migrants tend to arrive for the summer, and breed in the UK. ![]() Within the UK the majority of the migrants come in from mainland Europe. These two populations may even use the same areas, simply employing different strategies for coping with the approach of winter.ĭragonfly migration takes place on every continent aside from Antarctica. ![]() More confusingly, within some species, there are populations that migrate and others that don’t. Only a small proportion of species migrate, with most only moving a small way from where they emerge from their larval form into the adults. This is in part because the migration of small insects is more difficult to observe and track than that of larger animals like birds and mammals. Dragonfly migrationĪlthough we have been aware that many species of dragonflies migrate for over a century, the migration of dragonflies is still little understood. They aren’t designed to have a second go the following year, meaning that the adults tend to die by the end of the summer, not needing to enter hibernation. Once mating is complete, and the eggs are safely laid, their life’s work is completed. Within this time they will feed and hunt but their main aim is usually to defend a territory and bag a suitable mate. Most dragonflies will spend the largest proportion of their lives as larvae, only becoming an adult for a few weeks or months. In many insects, the main aim of their adult form is to produce offspring. Many dragonfly species can spend several years as larva, and therefore spend many winters living as juveniles within pools or watercourses.Īlso read: What Does a Dragonfly Eat and Drink? (Habits Explained) Do dragonflies hibernate as adults? This means they can cope with the cooler condition and are not growing, so do not need to hunt for food. Not all larvae remain active over winter. The downside is that larva also makes a tasty snack for other species, and are harder to hide than a tiny egg. This means it can continue to grow throughout the winter, and also change locations if conditions worsen. Overwintering as a larva has the added advantage that the dragonfly can move around and feed. Additionally, as long as the water is deep enough, ice may form on the top, insulating the water beneath. This is in part because water temperatures take longer to lose the warmth of the summer sun, keeping warmer for longer. Many dragonflies species overwinter in the water as larvae. They live within the water and spend their time hunting smaller invertebrates. Larvae are juvenile dragonflies, and can also be called nymphs. The downside is that the egg is not able to move, meaning that if conditions change, and become unsuitable for the egg, it may die.Īlso read: How Long Does a Dragonfly Live for? (Lifecycle Explained) Dragonflies that overwinter as larvae The small eggs are easily hidden from hungry scavengers and require little energy use throughout this time. There are benefits of remaining as an egg throughout winter. Entering diapause means they will stop developing until the weather warms, meaning they will spend the winter in an egg form, not developing any further. These eggs either enter diapause, which is a type of hibernation, or hatch out into larvae. Other species may lay their eggs outside the water, such as in slits the female dragonflies make in vegetation. ![]() Some dragonfly species can lay their eggs directly in the water, where they may sink to the bottom or become attached to aquatic plants. These eggs are laid usually at the end of summer after the adults have mated.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |