MONARCH Butterfly
An iconic and loved species, monarchs are easily recognizable by their striking orange wings laced with black lines and bordered with white dots that can reach nearly 5 inches. They are one of the planet’s most recognizable and well-studied butterflies. Their distinctively colourful pattern and colours warn predators that they’re foul-tasting and poisonous – a poison derived from feeding on the toxic Milkweed (Asclepias syriaca) that they have evolved to tolerate and use to their advantage by storing the toxins in their bodies and making themselves poisonous to predators, such as birds.
Male Monarchs tend to have larger wings than females and can be distinguished by a black patch on their hind wings; even the Monarch caterpillar (larva) is boldly patterned with black, white and yellow banding.
While the origin of the monarch butterfly migration from the US and Canada to Mexico each year is shrouded in mystery, scientists estimate that it takes three to five generations to repopulate the return journey from the overwintering grounds to the United States and southern Canada, however, they aren't sure how the migrating monarchs are able to find their way to their annual hibernation spot in Mexico each year since they live only a few months and none make the journey more than once.
COMMON NAME: Monarch butterflies or simply monarch, milkweed, common tiger, wanderer and black-veined brown depending on the region. SCIENTIFIC NAME Danaus plexippus
TYPE: Invertebrates
WEIGHT 0.0095 to 0.026 ounces
SIZE Wingspan, 3.7 to 4.1 inches
AVERAGE LIFE SPAN Six to eight months HABITAT In spring and summer, monarch butterflies can be found in open fields and meadows with milkweed. In winter they can be found on the coast of southern California and at high altitudes in central Mexico.
DIET Herbivore
GROUP NAME: Flutter
REPRODUCTION A female Monarch butterfly lays from 100 to 300 eggs that hatch about four days after they are laid. When they first hatch the larvae are less than 1 centimetre and grow to be about 5 centimetres. In as few as five days, the monarch completes the four stages of the butterfly life cycle from egg, to larvae (caterpillar), pupa (chrysalis), and adult butterfly.
PREDATORS Birds such as black-backed orioles and black-headed grosbeaks are common predators at monarch overwintering sites.
THREATS TO SURVIVAL The disappearance of milkweed and climate change are among the reasons for the decline in Monarch butterfly populations.
DISTRIBUTION Monarchs are divided into three separate populations: The western monarchs, which breed west of the Rocky Mountains and overwinter in southern California; the eastern monarchs, which breed in the Great Plains and Canada, and overwinter in Central Mexico and the third, a non-migratory population in Florida and Georgia.
There are also introduced populations of Monarch butterflies in the Hawaiian Islands, Portugal, Spain, Australia and New Zealand from where they are thought to be spreading around to other islands in the Pacific ocean on their own.