Monarch Lifespan

The Monarch butterfly is the most beautiful butterfly in the world, thus the name “Monarch,” honoring it as the “king” of the butterflies. Its orange color might have also contributed to its name in honor of the Prince of Orange.

It is also very unique because unlike all the other butterflies, this is the only species that migrates. The female butterflies have wings that are orange in color, with black margins and veins. The margins have small white spots. The forewings of the butterflies have spots near the tips that are orange in color. The hind wing of the butterflies has yellowish brown tips with larger spots than those located on the margins. The males are also brightly colored, with a black patch of scales on each hind wing. Their wing veins, however, are different from those of the females, because they are lighter and narrower.

The beautiful Monarch butterfly transforms from a caterpillar into a butterfly through a process known as complete metamorphosis, via four stages. The first stage is the egg, followed by the larva or the caterpillar, which transforms into a chrysalis, and the final stage in the cycle is the adult butterfly. These stages are completely different from each other. For instance, the caterpillar feeds on solid food while the adult feeds on liquid food.

But how long do Monarch butterflies live? Keep reading as we explore the Monarch lifespan and their life cycle stage by stage.

The Monarch Egg

The first generation of Monarch butterflies arises from the final generation of migrating butterflies, who return to their original location after escaping the winter. They mate before the migration commences so they only return to lay eggs.

While most of the other butterfly species lay their eggs in clusters, the Monarch butterfly’s eggs are laid singly. The most common location for laying is under the leaf of the milkweed plant, near the topmost part of the plant, close to its tender shoots. The laid egg is oval to almost conical in shape and it is very small in size. It is only as big as the tip of a pencil. The egg has a color that ranges from white to yellow, with ridges that run from the top to the bottom of the egg. The Monarch butterfly releases a sticky substance that helps attach the laid egg to the plant life glue.

An important characteristic of the Monarch eggs is that they are fully formed, with an outer shell, inside the butterfly before mating and fertilization occurs. The outer shell is known as the chorion and it aids in offering protection for the unborn larva. A layer of wax is lined all around the egg to prevent dehydration, which could lead to the drying up of the egg.

At the top of the egg is a tiny, funnel-shaped opening that is called a micropyle. The opening serves as an entry for the sperm in order to fertilize the egg. Oxygen and water also use the same hole while the larva is growing inside the egg. The egg shell contains ridges, which are raised areas on the egg’s shell. They are also formed before fertilization occurs.

The eggs take about 3 to 5 days to hatch. This is highly dependent on the temperature of the environment. If the temperatures are low, the egg will take longer to hatch. Before emergence, the caterpillar’s head can be seen at the top of the egg.

Since these eggs are laid singly, the Monarch butterflies have to mate several times in order to lay more eggs. During the entire reproduction stage, the average Monarch butterfly lays between 290 to 1180 eggs, of course depending on the number of times mating occurred.

The Monarch Caterpillar

After emergence from the egg, the Monarch caterpillar goes through five stages in order to grow and become a chrysalis. After completing each stage, the caterpillar molts to shed off overgrown skin because the skin cannot stretch. These stages are completed in a span of 8 to 15 days depending on the warm summer temperatures. It takes longer when the temperatures are low. The caterpillar growth periods are known as instars.

The first stage occurs immediately after emergence, where the caterpillar is translucent, meaning that it has no meaningful skin cover. During the first instar, the caterpillar is pale green in color. It looks fairly odd as it has no coloration or hair.

As soon as it emerges, it starts by feeding on the egg remains from which it emerged and then proceeds to feed on the leaf of the host plant. In order to avoid the sticky, milky substance, or the latex, the caterpillar feeds in a circular manner. At this particular stage, the caterpillar becomes toxic to predators . This arises from feeding on the milkweed.

In the second instar, the caterpillar begins to develop setae, which are short but very stiff bristles. A pattern of black, white and yellow bands also starts to form. The caterpillar grows two pairs of black tentacles , one pair on the abdomen and the other pair grows on the thorax. The third instar has the tentacles becoming much longer and the patterns on the caterpillar becoming more visible. In this stage of the growing caterpillar, legs are differentiated, where the ones on the thorax become a smaller pair and are now located close to the head. The larger pairs on the abdomen also move a little further away from the thorax and are located on the far end of the abdomen. At this stage, the caterpillar is big enough to eat the edges of the leaf of the milkweed.

The fourth instar involves the improvement of the band patterns of the caterpillar. White spots appear on the pro legs, which are next to the back of the caterpillar. Pro legs are small, leg-like structures that many caterpillars have, but they are much smaller than the actual legs. In the fifth and last instar, the caterpillar is fully grown and the parts are now very clear. The banding pattern is complete. The caterpillar has white little dots on the pro legs.

The front legs are quite close to the head compared to the other instars, and they also appear smaller. The fifth instar caterpillars have stronger jaws, and they can chew through the midrib of the milkweed leaf, disrupting and stopping the flow of the latex, meaning there is no longer a sticky substance to attach them to the plant. They therefore eat more tissue from the plant, growing much larger.

After about 10 days of continuous feeding, the caterpillar finally stops eating as it has finally completed its growth. It looks for a pupation site, usually a shoot or a leaf, and, after it has found one, it uses its hind legs to latch onto the plant. Using some silk, it hangs upside down. In this state, it molts one last time, remaining a blue to green opaque chrysalis, with small gold dots on the hard outer skin.

As stated earlier, the caterpillar feeds continuously during all the above stages, molting after the completion of each. After the fifth instar, you will find that the caterpillar is very large. In fact, it is 2,000 times the weight of the first instar. The caterpillar has also increased in length and width. During the first instar, the length of the caterpillar is 2-6mm long and it is usually 0.5 to 1.5mm wide. After it has completed growing, the caterpillar is now 25-45mm long and 5-8mm wide.

The Monarch Chrysalis

The chrysalis is the sessile part of the Monarch lifespan. This is the most delicate stage during the Monarch lifespan because all the parts of the caterpillar are broken down to form new structures that make the adult butterfly. This takes around 10 days. When the butterfly is formed and ready to come out of the shell, the chrysalis becomes transparent, clearly showing the butterfly in the chrysalis.

The primary method for determining the correct emergence time, however, is by looking at the top of the chrysalis, where the butterfly’s abdomen is located. This part expands, begins to separate, and slightly pleats. Not very long after this, the butterfly emerges, using two techniques. First, the butterfly uses the help of a liquid found in the shell, known as cocoonase, which aids in softening the hard chrysalide shell in order for the butterfly to come out. Secondly, the butterfly makes use of its two claws which are located at its joints under the front wings to rip open the hard shell.

If the chrysalis stays transparent for more than 48 hours, your butterfly will not emerge as it is probably dead. If you have a school kit or a home butterfly kit, and you notice the butterfly struggling in the chrysalis, you can carefully tear the chrysalis to help it emerge.

The Monarch Adult Butterfly

After the emergence of the adult butterfly from the chrysalide shell , it does not adapt to its new body immediately. On the contrary, it is a bit of a challenge for the butterfly to even fly. This is because it’s a damp mess, with its small wings stuck to the abdomen. The butterfly is also plump with an abdomen full of a fluid known as the hemolymph.

To repair these unfavorable conditions, the butterfly has to hang downwards in order for the wings to expand and dry up. Expansion occurs through the distribution of the abdomen fluid to the wings, which makes the wings stronger and stable. At this drying stage, the butterfly also forms a proboscis through the fusing of the mouthparts known as the labial palps.

There are certain precautions that accompany the new transformation that must be keenly observed as they determine the future of the Monarch butterfly. If the newly formed butterfly does not hang downwards after emergence from the chrysalis, the wings will remain small and wrinkled and the butterfly will never fly. If the butterfly falls while it is hanging downwards, it has to be returned to this position in order for the wings to completely expand.

Besides secreting the abdominal fluid, the butterfly also expels a fluid from its anal opening, known as meconium. This is metabolic waste that accumulates during the transformation inside the chrysalis. It is completely normal for the butterfly to release this fluid. It is reddish in color and it is released about an hour after emergence.

After the butterfly has survived the delicate chrysalis stage and hardened its wings, it flies around and feeds on nectar from different flowers using its proboscis. It unfolds its proboscis to siphon nectar and when it is done feeding, it safely folds its proboscis back to its place under its head.

Most generations of the Monarch butterfly takes 4 to 5 days to attain sexual maturity, while the migrating generation does not reach sexual maturity until the winter is complete, and only then can they mate and lay eggs.

Reproduction and Monarch Life Span

Reproduction for the Monarch butterflies is different from the other species of butterflies. It is made unique by the migratory behavior of this particular species. Mating occurs several times per generation in Monarch butterflies in order for them to lay many eggs. When mating occurs, the males not only release the sperm to the female, but they also transfer some nutrition to them, which comes in handy when the female needs to lay her eggs. The sperms of the Monarch butterflies vary in size, with larger spermatophores producing larger butterflies and vice versa.

During summer, the adult butterfly mates and undergoes a complete life cycle to give rise to the second generation of butterflies. The normal Monarch lifespan is two to six weeks. The third generation follows the same pattern. These butterflies mate and, as fall approaches, they lay eggs which produce the fourth generation of Monarch butterflies.

These are the butterflies that will migrate south from November to May. They will fly to their winter grounds in Mexico and California. These butterflies are non-reproductive, meaning that they do not reproduce until the following spring. Due to the thousands of miles that they will have to travel, they store lots of fat in their abdomens for the trip and for survival through cold areas. They stay in their winter breeding grounds for five months, inactive while forming clusters as it gets colder.

When the winter is over, they gather nectar, reproduce, and their life cycle ends. In total, the Monarch lifespan of this generation is months compared to weeks. Their offspring make the trip back north with the fifth generation returning to their ancestors’ original home in the spring. Then, the process starts all over again. The Monarch butterfly migration is different from other animals because it is a one- way migration.

How Long to Monarch Butterflies Live?

There are many factors to take into account regarding the Monarch lifespan. The eggs could be eaten by birds. That’s why the mother butterflies lay and stick them to the underside of leaves.

The caterpillars could be eaten by birds or rodents. The toxicity from the milkweed helps ward off repeat predators.

The chrysalis could be damaged or disturbed. The chrysalises are green, helping them to blend in with surrounding plants to protect them from interference.

The butterfly could fail to emerge from the chrysalis. When they do emerge, they are very vulnerable until their wings expand and dry. But even during flight, Monarch butterflies are delicate creatures that can’t survive cold weather or rough handling.

But if all goes well, the Monarch life span from egg to butterfly is approximately 40 days. But that’s only for the first 3 generations of the season. Monarch lifespan for the fourth generation can be as long as 7 months. This gives it time to migrate in the fall and then reproduce in early spring.

Conclusion

The life cycle of the Monarch butterfly is highly dependent on the temperature and density of their environment. While the normal Monarch lifespan only lasts for 40 days, when it gets cold, it can be up to 7 months.

The Monarch butterfly species is unique and special, and due to the many risks that it has to endure in order to survive, it is justified as being the most beautiful butterfly in the minds of many.

If you have kids, help them learn about the Monarch lifespan and answer the question, “How long do Monarch butterflies live?” by giving them a copy of National Geographic Kids 'Caterpillar to Butterfly' Issue . It’ll answer all their questions with the high-quality photos the magazine is known for.