Story Behind the Science
Butterflies, specifically those of the Nymphalidae family, enjoy basking in the sun near mud puddles. This curious behavior may be for multiple reasons: butterflies open their wings to capture sunlight and bask in the heat to raise their body temperature, and they also like to drink the water that gathers in mud puddles.
Butterflies are cold-blooded insects, so their bodies cannot produce heat without an outside source like the sun. This is also a potential explanation for why many butterflies have dark-colored wings, since darker colors attract more heat. The water may seem dirty to humans, but for butterflies it is rich with nutrients that are crucial for their survival. When a butterfly is given the choice to drink from clear freshwater or salty rainwater, it will more than likely choose the saltier option.
This practice, called mud puddling, was first reported among moths and butterflies (which make up the higher classification Lepidoptera) in the 1800s. It wasn’t till the 1900s, though, that scientists suspected that the water’s sodium content was the reason.
Because nymphalid butterflies are so delicate and sensitive to environmental changes, they are highly affected by threats like habitat loss and climate change.
Millions of monarch butterflies, for example, migrate to warmer climates during the winter season, resting in the mountain forests of Mexico. Local communities depend on these same forests for agriculture and tourism, which has disturbed the natural order of the monarch butterflies’ migration. Additionally, illegal logging in Mexico has caused devastation for monarch butterflies during the winter months, as it is one of the primary causes of habitat loss concerning their seasonal migration. In the U.S., increased use of herbicides has negatively impacted the milkweed plant, the only source of food for monarch caterpillars.
If not regulated and helped, the monarch migration, as well as the migration of other nymphalid butterflies, may be severely threatened in the coming years.
Did You Know?
- Nymphalid butterflies are commonly known as brush-footed butterflies because the adult’s forelegs are small, hairy and resemble mini brushes. Nymphalids often appear to have only four legs because their forelegs are extremely small.Learn More »
- Nymphalidae is the largest and most common family of butterflies.Learn More »
- Most nymphalid butterfly species have long antennae that have rounded clubs at the end.Learn More »
- If a monarch butterfly’s body temperature drops below 86 degrees, it can no longer fly. To warm up, the butterfly will “shiver” its wings while basking in the sun.Learn More »
- The migration pattern of the monarch butterfly is so highly evolved that it is unmatched by any other moth or butterfly, and perhaps even by any other insect.Learn More »
- Monarch butterflies can travel up to 3,000 miles during migration each winter.Learn More »
|Compare & Contrast||Nymphalid Butterflies||Monarch Butterflies|
|How many species?||About 6,000||1|
|Where do they occur?||Nymphalids are common worldwide. This group includes so many species that they can be found in a wide range of habitats.||Monarch butterflies are located mainly in North America (typically south of Canada) and throughout South America. They’ve also been introduced to Hawaii and Australia. Monarchs are most common in forest and mountain habitats.|
|What do they eat?||Nymphalid caterpillars feast on a variety of plants, but adults usually sip nectar, tree sap or the juices of rotting fruits. Many nymphalids are attracted to the mineral-rich mud found near river beds.||Monarch caterpillars only feed on milkweed. As adults, they can feed on the nectar of a variety of flowers and juices from other sources, such as fruits.|
|Do they have predators?||Wasps, bees, ants, mantids, spiders, beetles, frogs, rodents and birds||Few birds and insects. Some predators have adapted to the poisonous nature of monarchs, such as a species of mantid and various birds. Some of these birds include jays, orioles, robins, cardinals, sparrows and more.|
Discovery, “Life - Monarch Butterfly Winter Migration | Insects”
Conservation Organizations for Butterflies & Monarchs
- Butterfly Conservation: Saving Butterflies, Moths & Our Environment
- Butterflies & Moths of North America
- The Butterfly Conservation Initiative
- Protecting Monarch Butterflies & Their Forests, World Wildlife Fund
- Monarch Butterflies, The Xerces Society for Invertebrate Conservation