Born on the Fourth of July

In the sweltering heat of this sultry Independence Day, we managed to get some very good pictures of a Zebra Longwing butterfly ovipositing, or laying eggs, on our passionvine.

A close-up of the eggs reveals the ridges and pointed oval shape. This egg shape is common to the three heliconian species (Zebra Longwing, Gulf Fritillary, and Julia Longwing) that lay on passionvine, though the colors and laying habits differ among species.

In the photo below, note the butterfly's proboscis - it's completely covered in pollen. Zebra Longwings are among the very few species of butterflies that can digest pollen in addition to nectar. (They digest it externally, on their proboscis.) The extra energy from this pollen protein extends their lifespan dramatically - most butterflies live about two weeks as adults, but Zebra Longwings can live as long as six to nine months. As I tell kids at the museum where I work, imagine if you only drank soda all day long - how long would you live? Then imagine adding daily steak to your diet - now you have the extra nutrients you need to live a much longer life.

Zebra Longwings seem to be a fairly permanent fixture in My Florida Backyard these days, for the first time since we moved in nearly five years ago. It's fun to have Florida's State Butterfly hanging around as we celebrate our national holiday!

Differences

After discovering our first Zebra Longwing caterpillars ever in My Florida Backyard a few weeks ago, we're now noticing clutches of eggs on the passionvine too. Passionvine (Passiflora spp.) is a popular host plant. In Central Florida, it's used by Gulf Fritillaries and Zebra Longwings. Further south, it's used by Julia Longwings, and to the north by Variegated Fritillaries. (Learn more about all these butterflies and caterpillars here.)

The eggs of Zebra Longwings and Gulf Fritillaries look very similar, but due to the laying habits of the butterflies, you can actually tell them apart pretty easily. Zebra Longwings lay eggs in clusters at the ends of vines, while Gulf Fritillaries lay their eggs singly, often on the upper sides of leaves. (The pictures below aren't of the greatest quality, but they help explain the point.)

Zebra Longwing Eggs

Gulf Fritillary Egg

Once hatched, the caterpillars have similar feeding habits. It takes them about two weeks to grow full-size and pupate to chrysalis. They then spend about two weeks hanging in chrysalis before emerging as butterflies. Gulf Fritillaries round out the life cycle by spending about two weeks feeding and mating before they die, but Zebra Longwings are actually much longer lived as adults. They are one of the few butterflies that possess the ability to digest pollen in addition to nectar, allowing them to expand their lives as butterflies to as much as six months or more. The pollen collects on their proboscis and is digested externally (click here to see a picture of a Zebra Longwing with collected pollen) - a cool and unusual process in the insect world.

We love nature of all sizes in My Florida Backyard, but we're especially fond of it on a small scale. It's endlessly fascinating to flip a leaf and see what's beneath!

Skipping 'Round the Garden

Not all butterflies are big and colorful. Some are small and need to be seen up close to be truly appreciated. Case in point: the Long-Tailed Skipper (Urbanus proteus). This diminutive butterfly is only a couple of inches in size, and seen in flight might appear to be a drab brown. But take a closer look - there's more than first meets the eye.

Long-Tailed Skippers lay eggs on a variety of plants in the pea and bean family (Fabacae). In the past, we've had Long-Tailed Skipper caterpillars on Hairypod Cowpea (Vigna luteola) and Creeping Beggarweed (Desmodium incanum). We've grown green beans and peas for them, too. This year, we have a new "volunteer" host plant for these skippers, Dixie Tick Trefoil (Desmodium tortuosum), a non-native that has naturalized in the southern US. A seed from this plant most likely hitched a ride home from the butterfly garden where I work, and has taken hold and grown... and grown... and grown. This plant is now well over six feet tall, and the leaves are kind of like condominiums for skipper caterpillars.

Skippers are leaf-rolling caterpillars. They use silk to pull the leaves around them to protect them while they eat. The leaves of D. tortuosum are soft and textured in a way that actually makes them stick to each other very easily, rather like Velcro. Perhaps this helps the caterpillars with the rolling?

Long-Tailed Skippers lay their eggs in stacks several high. We managed to catch this one in the act of ovipositing the other day - if you click the picture to enlarge it and look very closely, you can see the eggs she's already laid on the leaf at the end of her abdomen.

The light wasn't great, but we didn't want to disturb her, obviously. We did flip over the leaf and get a better shot of the eggs themselves when she was done.

Long-Tailed Skipper caterpillars have fun little heads, shaped almost like the peas and beans from their host plants. This caterpillar looks similar to other skipper caterpillars, like the Dorantes Skipper, but is easy to distinguish due to its bright orange hind end.

When ready to pupate, the caterpillar rolls itself up one final time for a safe place to transform into chrysalis. The chrysalis of the Long-Tailed Skipper is coated in a powdery substance that is a actually wax (click here to see a picture). After a couple of weeks, they emerge as butterflies to begin the process again.

Big or small, the butterfly and its life process is fascinating. We're so glad to have such a wide variety of species in all parts of their life cycle here in My Florida Backyard!

Pink Houses

This weekend, a splotch of pink suddenly appeared on the trunk of our little cypress tree.

Upon closer inspection, we discovered a clutch of apple snail eggs.

Apple snails (family Ampullariidae) are freshwater snails that are able to survive both on water and on land. By laying their eggs above the water line, apple snails protect the eggs from predation by fish and other water dwellers.

Apple snails are the primary food source for limpkins, a common wading bird in My Florida Backyard. Limpkins have specially adapted beaks that curve slightly to one side, allowing them to easily extract the apple snail from its shell. Limpkins will only live in areas with large apple snail populations, so they are found only in scattered locations throughout Florida in the United States. We feel very lucky to have this bird as a regular visitor here in our yard, and we owe that to the apple snails and their pretty little pink eggs.