The Intractable Autodidact

You are your own best teacher

Lost & Found—the Atala Butterfly

Let’s look at another Lazarus species (believed extinct but found alive). This time, let’s choose an animal:

I present the beautiful little gem that is the atala butterfly.

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The atala butterfly, Eumaeus atala

This sparkling South Florida beauty, black with metallic aqua spots and cheeto-orange markings and abdomen, is a classic case of interdependence, where removing one piece of the puzzle affects all the other pieces. You see, the atala lays its eggs on a particular plant, the host plant on which its larvae depend for food. That plant is the coontie, America’s only native cycad. Coontie looks like a small (a foot or so tall) palm tree, with tough pinnate leaflets. As a gymnosperm, it reproduces by producing a cone, somewhat similar to a pine tree.

Extinction loomed for the atala because coontie root could be made into a flour of sorts. Florida’s Native Americans grated, washed, and pounded the root into a starch for generations. When settlers/invaders settled here in Florida, they did the same, but on a modern, industrial-revolution scale. The result, arrowroot starch, fueled a small industry from the late 19th century into the 20th. (Note: cycads are toxic. The thorough washing of the “flour” supposedly removes the toxin, but over time its accumulation is harmful.)

The ratio of coontie to starch was about 5:1, so if you want a pound of starch, it takes five pounds of coontie root. This decimated the plant’s population, and consequently, the atala. No coontie means the atala caterpillars have nothing to eat, though I (and others) have seen them eating the foliage of closely related, non-native cycads—no where near enough, however, to support the species.

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An atala caterpillar consuming coontie foliage

Still, into the 1920s atalas were noted as common. A sudden population crash must have happened soon thereafter, since the last record of them was made in 1933.

Then in 1961, George W. Rawson wrote*:

Within the last three or four years there have been “guarded reports” of small colonies of atala in wild or secluded places in southeastern Florida; but the first authentic record was obtained on 28 February 1959, by Mr. JACK DEMPWOLF’S father, of Westfield, N. J., who secured a few specimens from a small colony while on a vacation trip. This locality has been kept a secret for what might be termed “Security Reasons”.

Mr. Rawson, lepidopterists and Everglades National Park staff apparently captured atala females in a re-introduction attempt in the Everglades. He states that although they were successfully reared in captivity, no populations were established in the wild.

On saving the atala, he wrote:

“I therefore hope that this paper will create sufficient interest so that we can, either individually or collectively, organize or formulate plans for further action.”

This has indeed happened. At my place of employ, Fairchild Tropical Botanic Garden, there is a thriving, self-sustaining atala population. The larvae absolutely decimate the coonties on display, but the dedicated horticulture staff replenish them regularly. It’s interesting to notice the adult atalas feeding from plants they’d never naturally encounter, like the flowers of Triplaris cumingiana, the tropical longjohn tree. I have yet to discover who introduced these atalas to Fairchild, and when, though they were introduced. They are a wonderful sight to behold.

* “THE RECENT REDISCOVERY OF EUMAEUS ATALA (LYCAENIDAE) IN SOUTHERN FLORIDA,” by GEORGE W. RAWSON, Journal of the Lepidopterists’ Society, 1961, Vol. 15 (4) 237 – 244.

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