The red admiral butterfly (Vanessa atalanta) is a common butterfly found in most areas of North America and Europe. They live mainly in woodlands where they feed on flower nectar, tree sap, and overripe fruit. The name of this medium-sized butterfly comes from the distinctive red band on its black wings.
Red Admiral Caterpillar
Like all butterflies and moths, they start their life as caterpillars. After hatching from eggs, the caterpillars grow to about 2.5 cm (1 inch) long. The caterpillars are black and have a fuzzy appearance due to hairy spines covering their body. You can usually find the caterpillars on stinging nettle plants (Urtica dioica). These hungry larvae munch their way through nettle leaves as they reach the pupal stage.
The length of metamorphosis depends on the air temperature. In climates where temperatures average 32°C (90°F), the time from caterpillar to butterfly may be as short as six days. In wintertime, when temperatures drop to around 7°C (45°F), the pupal stage can take as long as 80 days.
After the pupal stage, when the caterpillar becomes a chrysalis, a beautiful butterfly emerges from the cocoon.
Identifying these Butterflies
They are easy to identify and not hard to miss. These delightful butterflies belong to the largest family of butterflies called Nymphalidae—of which there are over 6,000 species.
They have a wingspan of between 5 and 7.5 cm (2 – 3 inches) with a slender black body. The identifying feature of these butterflies is their black or dark brown wings with white and red patterns. Compared to other butterfly species, they are in the medium-sized range.
Each wing has a line of bright reddish-orange blotches running down the middle. These marks are also on the bottom part of the wing. On the tips of the fore wings, you will notice some randomly-placed white dots.
The underside of the wings, ventral side, has similar markings as the upper side, dorsal side. However, the coloring on the ventral wings is duller than the dorsal side. Also, the dorsal hind wings have mottled patterning. These black and brown patterns act as camouflage when the butterfly sits on branch or perch with its wings folded upward.
There are also differences in red admirals that emerge from the chrysalis in summer and winter. The ones that emerge in the summer tend to have brighter, more pronounced wing markings, whereas winter ones have duller tones.
What They Like to Feed On
These butterflies are common pollinators, and because of that, they feed on the nectar of various flowering plants. These butterflies feed on the nectar of buddleja (buddleia), milkweed, asters, and alfalfa flowers. They are also known to eat rotten fruit and even bird droppings.
From all flowering plants, buddleia is there favorite. This plant attracts so many types of butterflies that it also has the common name butterfly plant. So, if you want to attract butterflies to your garden in the summer, plant plenty of buddleias. In the fall, put out rotten fruit on perches to attract these flying insects as they migrate south.
Where They Live
Although commonly associated with North America, they live in most temperate and hot regions of the world. You can find them in North Africa, Asia, New Zealand, Europe, and Central America. The favorite habitat of these red and black butterflies is woodlands. However, you will also find them fluttering around parks, marshes, fields, and in yards.
The ones that live in temperate regions are also migratory butterflies. When the weather cools, they will leave their natural habitat in Northern America and Northern Europe and fly south. Research has shown that red admirals can migrate considerable distances to reach their destination. Other studies have found that some groups of admirals form mass migrations in the fall to overwinter, in warmer countries.
Most species of red admiral butterflies that live in warmer regions don’t migrate. The butterflies live for between six and nine months and use their time pollinating woodland and garden flowers.
How Common Are They
These beautiful butterflies are a common, especially in areas where their host plants are in abundance. So, you often find them in open areas near woods where plants such as milkweed, asters, and stinging nettles are common.
Usually, you will see them fluttering from flower to flower in mid-afternoon and evenings. The males are very territorial and will defend their territory from other males. This type of behavior also makes them attractive to the female who only mates with males that have their own territory.
Because there are many species of black and red butterflies, it can be easy to confuse red admirals for other butterflies.
For example, admiral reds are similar to the related species, painted lady butterflies (Vanessa cardui). The difference between these two species is that the admiral’s wings are predominately black to dark brown. Painted ladies have orange and black wings with white speckles.
Also, some people confuse the famous monarch butterfly (Danaus plexippus) with them. However, monarchs have orange wings with black lines and a series of tiny white dots along the wing margins.
In conclusion, this butterfly is a common butterfly species in many countries. These black and red flying insects are useful pollinators where they feed on the nectar of many flowering plants.