January 4, 2014

A Tale of Three Hairstreaks

One of our objectives on our recent trip to Florida was to try to expand our Florida butterfly list. December isn't the greatest time to do that, but we figured we'd at least give it a try, and we were actually pretty successful. 

We were especially hoping to see some hairstreaks, butterflies that are usually have hair-like projections on their hindwings that look almost like antennae and are probably designed to make both ends of the insect look like its head. Predators are often fooled into grabbing the wrong end, and the prey flies off with just some tattered hindwings. Most hairstreaks are pretty tiny, and you have to get binoculars on them to tell what they are and to appreciate their beauty. 

One of the hairstreaks that we especially wanted to see is atypical in that it doesn't have the hindwing projections; taxonomists have included it in the group anyway. This insect is called the Atala, and is one of the rarest butterflies in North America. 

At one time it was fairly common, because its larval food plant, the coontie (Zamia integrifolia), was common in the pine flatwoods of Florida. Beginning with the native Americans, however, coontie was harvested for the starch in its large tuberous roots. By the early 1900s, several industrial facilities were harvesting the plant, particularly to make arrowroot biscuits.

Coontie is a cycad, and some people have described it as a "living fossil" since cycads are pretty rare in the western hemisphere north of the tropics today but were quite common in Jurassic times. Coontie is dioecious, meaning that it has separate male and female plants. Here is a picture of the cones on the male plant:



and here is the female plant.



Once the cone on the female plant matures it crumbles and bright orange seeds are revealed.



With the harvesting of so much coontie, the Atala butterfly was thought to be extinct in Florida. Recently, coontie has been recognized as a valuable landscape plant and is appearing in south Florida gardens. Atala caterpillars have been introduced in some areas, and populations have begun to grow where there is plenty of coontie. 

When we were planning our trip, we called around to several nature centers that have butterfly gardens to see if they had any Atalas, and a couple of them sounded promising. First we went to Gumbo Limbo Nature Center, near Boca Raton, which is within Red Reef Park. The beach part of the park was stunning and uncrowded early in the morning:



We weren't disappointed by the butterfly garden at all. Wandering through the paths, we found at least a dozen Atalas in all their gorgeousness. This has to be one of the most beautiful insects around, with its "starry night" wings, orange abdomen and adorable face!


We even found one that had just emerged from its chrysalis, and was still pumping fluid from its abdomen to its wings:


The other place that we saw it was Daggerwing Nature Center, west of Boca Raton. At both of these butterfly gardens the Atalas were there naturally and were not introduced. 

After that excitement we poked around many other beaches and preserves and then headed north to the Titusville area. All along the way we had been reading signs about a very invasive plant, the Brazilian pepper, that is choking out native vegetation. It forms dense thickets, and efforts to eradicate it are extremely labor intensive. It is native to Argentina, Paraguay, and Brazil, and was introduced to Florida as an ornamental.

We talked to some biologists in the Everglades who told us how hundreds of acres had to be scraped down to the bedrock to get rid of the plant, and then the debris was piled into a large hill that we hiked up a couple of years ago! Interestingly, the hill now supports a variety of wildflowers and butterflies. It is attractive, and like Ohio's nemesis, the honeysuckle, many people like the fact that it provides a screen. It is very bad for native wildlife though! Here is a photo of it--we saw dense patches of it all over Florida and it apparently is spreading northward:



Anyway, as we were checking out a natural area near Titusville, we noticed a small hairstreak butterfly, nectaring on a passion flower. It was unfamiliar to us and to the friend we were with, who is quite knowledgeable about Florida butterflies:



I went back to the car and got my field guide and pretty quickly matched my photo up with a picture of the Fulvous Hairstreak (fulvous means reddish). Looking further at the field guide entry, I saw that its caterpillar food plant is none other than the Brazilian pepper, which formed a dense hedge behind where the butterfly was nectaring! The field guide showed its range to be quite a bit south of where we were, but with the spread of the peppers the butterflies seem to be extending their range as well. In fact, our friend was going to check to see if this was a new county record.

A third hairstreak from this trip was memorable because the instant we got our binoculars on it we recognized it from home: the Red-banded Hairstreak:



Here is a picture of another individual that shows the hindwings a bit better:



This lovely insect is near the northern edge of its range in Ohio; we have seen it at Clear Creek Metro Park. It is, however, more common in the southeast. The females lay eggs on the leaf litter beneath the caterpillar food plant, usually wax myrtle (in the south), sumac and oaks. The caterpillars actually feed on the fallen leaves.

So there are three of the more interesting butterflies that we saw, and each has its own unique story. But in each case, their range is dependent on the presence of specific caterpillar food plants.


1 comment:

  1. You tell a wonderful, informative story about plants and butterflies and the photos are amazing -- especially capturing the Atala emerging from its chrysalis. When will we ever learn not to introduce non-native plants?

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