INSECTS: DRAGONFLY, DEWY RINGLET, COMMON CARDER BEE, MOURNING CLOAK

Dragonfly (pl ważka)

The history of the dragonfly stretches back to carboniferous period of the Palaeozoic era, when the granites of the Tatra mountains formed. The prehistoric dragonflies of that period, with wingspans of over 70 centimetres, were the biggest insects in the history of our planet. Modern dragonflies can grow to substantial sizes as well, as the biggest dragonfly of the Tatra mountains, known as the emperor dragonfly or the blue emperor, has a wingspan of 11 centimetres and body length of 8 centimetres. It is a true giant of the insect world! The four-spotted chaser is a kind of a dragonfly living in the Tatra mountains that is a little smaller than the emperor dragonfly, however, it is still quite big, as it reach the wingspan of 7 centimetres. So far the scientists have found 25 different species of dragonflies living in the Polish part of the Tatra mountains.

In the Tatra mountains the dragonflies reproduce in lakes and other water reservoirs located mostly in the lower montane zone, i.e. Stawy Toporowe. Only a few species live in the upper montane zone, although it is not surprising to see a dragonfly above the tree line, as they can be carried there by the air currents.

The larvae of the dragonfly are predatory and hunt other water organisms. They are big enough to hunt even polliwogs, although most often they hunt larvae of other water insects. Of course, the dragonflies have enemies of their own, such as the fish, frogs and toads. Before their eclosion the larvae crawl on plants growing above the water, where they leave their molts as mature insects. The adult dragonflies leave their molts through cracks at its top and pump their wings with air. The empty molts are left on the leaves. The adult dragonflies are predatory as well and hunt other insects, which they catch in flight.

The dragonflies resemble helicopters and, like the machines, can both hover at one point and move around very quickly. They have two pairs of wings which they incline on sides or up while they rest.

Despite their looks they are not harmful to humans. On the contrary, they may be seen as our allies, as they hunt flies and mosquitos. In turn, they are prey for birds, reptiles, spiders and bigger species of dragonflies.

Dewy ringlet (pl górówka pandroza)

The dewy ringlet is a butterfly of the Nymphalidae family. They mostly live in the mountains. They are relatively tiny insects with colourful accents on their wings and wingspan of 4 centimetres. Like other butterflies, the eyes of the dewy ringlets are compound and consist of many smaller eyes, which is why they have mosaic vision.

The wings of the dewy ringlet are covered with extremely thin scales which are only one cell thick. They absorb and reflect the light and make the butterfly’s unique patterns of colour. The young specimens have much more vivid colours than the older ones, as their scales wear down with age.

The dewy ringlet butterflies were once associated with Lapland, as in Europe they only live high in the mountains and in the tundra regions of the northern part of the continent. In Poland they may be found exclusively in the Tatra mountains, from the upper treeline to the highest mountaintops.

The eggs of the dewy ringlet are green, which makes them camouflaged on plants such as the matgrass, the fescue grass or the sesleria albinica, where the butterflies typically lay them. The larvae of the dewy ringlet are green with brown heads and covered with thick hairs.

In the challenging climate conditions of the mountains the larvae of the dewy ringlet wait two years for their metamorphosis. After their first year of living they spend the winter still in the form of larvae. Then, once the ice caps melt, they change into brown chrysalises. After about two weeks the chrysalises change into mature butterflies. The butterflies are active from June to end of August and during that time they have to mate in order to reproduce before their imminent deaths.

Common carder bee (pl trzmiel rudy)

The common carder bee is one of the twenty-two species of bumblebees that live in the Tatra mountains. It is very distinctive among other bumblebees because of its characteristic colours – it has a ginger back and a grey abdomen. The bumblebees are often confused with the bitterns, although they are a completely unrelated species.

While flying the bumblebees substantially rise their bodies’ temperature. That allows them to fly and gather pollen even when the temperature outside is only 10° C, while other, rival insects are incapable of flying.

Only young, female bumblebees that mated at the end of summer are capable of surviving winter. At early spring female bumblebees leave their lairs and look for appropriate places to nest. After that, they look for pollen and nectar. The common carder bees make their nests in crevices of boulders and abandoned mouseholes. One of the first flowers that the bumblebees visit after winter are the crocuses. The females lay their first eggs in their new nests and look after them for about 21 days. Then, once the first worker bees mature they start to look after the rest of the eggs and their mother. The female bumblebee and later the worker bees hatch the eggs and warm them with the heat of their bodies. In a friendly environment there may be even a hundred members in such a ‘family’.

At the end of summer there is a new generation of male and female bumblebees in the nests. After some time they left their nests in order to mate. Then, once again, the young females look for lairs to hibernate and the old mother, male bumblebees and workers gradually die.

The life of the common carder bees is always in danger because of predators and parasites. Their nests may be attacked by rodents that often feed on the larvae. There are also parasites, like the cuckoo-bumblebee. They look like bumblebees but once they get in their nests they kill the female bumblebee and lay their own eggs, which are later looked after by the workers. Then, after some time it is not a young generation of bumblebees that leave the nests but young cuckoo-bumblebees.

Mourning cloak (pl rusałka żałobnik)

The mourning cloaks are large day butterflies with wingspan of 7-9 centimetres. Their colours are very characteristic as their black wings have blue spots and yellow-white rim.

In the Tatra mountains the mourning cloaks reproduce in deciduous forests which grow mostly in the lower montane zone. The females lay their eggs on the twigs of birch-trees, willows and aspens. The insects go through their metamorphosis in the middle of summer and then they have a whole year as mature butterflies to live and feed on sweet sap leaking of the damaged twigs of deciduous trees. Over the course of time the colours of their wings fade and their wings become ragged. Sometimes they even have holes from birds’ strikes – if they’re lucky enough to survive such an attack.

The mourning cloaks are excellent flyers and appear in all the places that they can reach with air currents. Their dark colours are easily noticeable and are often associated with bereavement and mourning. Many of the mountain folks believe that if you see a mourning cloak flying over snow in spring someone dies at the mountains. People also used to be afraid of the mourning cloaks spending winters in their houses, as it could mean that some its residents would soon die. It’s worth mentioning that, like some people, the mourning cloaks are very fond of alcohol. During fall they gladly feed on the fruits that ferment on the trees.