Kirtland's snakes are highly fossorial, living a secretive and subterranean lifestyle. They are very much associated with crayfish, since they utilize their burrows as refugia in all seasons. Because of their dependence on crayfish, Kirtland's snakes are never found far from wet areas such as mesic prairies, meadows, fens, open woodland, and similar environments. Living in holes underground, it isn't very difficult for the Kirtland's snake to find its food - chiefly worms. During heavy rains, Kirtland's snakes will surface, but usually avoid exposure. Sometimes they can be found underneath logs or artificial cover such as discarded boards, roofing shingles, or sheet metal.
Long ago, prior to the draining of wetlands and the destruction of prairies for agriculture, the Kirtland's snake was much more common than it is today. Nowadays, their occurrence is very sporadic. In the Chicago area, they are restricted to a few tiny patches of habitat - a mere fraction of what they once enjoyed. Not very long ago, it wasn't unusual to find them in empty lots in Chicago, as well as smaller cities and towns in the region. Kirtland's snakes were known for persisting in less-than-ideal habitat, that is, until degradation become so severe that one of several things happened - the water table sank, the crayfish died, or in some cases, all the snakes were captured or killed off. Though some Kirtland's snakes today can be found in degraded habitat, the habitat must include at the very least fair enough conditions to allow crayfish to survive, and must be large enough to ensure a viable population of snakes. The smaller the population, the less variety of genetic material to pass on to the next generation.
In my opinion, with the exception of perhaps the plains garter snake (Thamnophis radix), no other snake best embodies the spirit of Chicago area herpetology as it pertains to natural history as the Kirtland's snake. The Kirtland's snake's storied beginnings as we know it all started with famous naturalist and explorer Robert Kennicott, who collected the type specimen in what is today Glenview, IL, and described it in 1856. He named it in honor of Dr. Jared Potter Kirtland, a mentor of Kennicott. As Kennicott became famous as both a naturalist and explorer, so did the Kirtland's snake, to leagues of herpetologists and amateur field herpers who sought out the elusive denizen of swampy areas and wet fields. To this day, the Kirtland's snake remains a target for many who have an interest in local snakes. Many have never seen one. Their unwillingness to appear during searches, coupled with their rarity, has turned the Kirtland's snake into a sort of "white whale" for many. Ideally, the last few strongholds for the Kirtland's snake in the Chicago region should be restricted to all but the most appropriate personnel - land managers, researchers, herpetologists - both they aren't. Some populations have been stomped down by well-intentioned (or sometimes, not so well-intentioned) folks who seek the snakes for photographs or for the pet trade. As Kirtland's snakes make poor captives, there doesn't seem to be any rhyme or reason for capturing Kirtland's snakes to sell in the black market pet trade. People will still do it for status or ego boosting. Each Kirtland's snake that is harmed is another hit to the already perilous wild population (remember that natural predation doesn't go away just because the Kirtland's snake is rare; though there are less to be seen and therefore eaten, a heron or raccoon would not hesitate to take one as a snack if the opportunity arose).
In my field excursions, I always look for telltale signs of Kirtland's snake habitat when the opportunity arises. It would be very surprising if any additional populations were discovered in the Chicago area. As early as the 1940s, the species was known to be rare in the Chicago area (Pope, 1947). Pentecost and Vogt (1976) also noted its rarity. A population in northern Cook County that once persisted in a power line cut hasn't been observed since 1986 (Anton, 1999). A population in southern Cook County persists in a small, well-managed restored prairie (this could represent the final stronghold for the species in Cook County). Other known populations have been exterminated due to development in the area (T. Anton, M. Ignoffo 2014, pers. comm.), and any possible remaining populations would be under heavy threat of extirpation due to development or invasive species. (An ongoing study I've headed up over the last few years, and particularly this past year, is the survey of an urban scrap of undeveloped land [DRCA] for any proof of the existence of Kirtland's snakes.)
Without a doubt, the best population of Kirtland's snakes in the Chicago area occurs in Will County. With two known localities located on Forest Preserve District of Will County (FPDWC) property (Anton, 2007), it is imperative that the snake's habitat not only remains protected, but properly managed. The snakes in Will County are consistently found during cover board surveys, but low rates of recapture along with other variables ensure that monitoring will remain challenging (Mauger and Anton, 2015).
In early September, I went down to the Will County habitat to observe the snakes' habitat, in part to learn more about how I might find Kirtland's snakes in my own surveys of urban plots. I met once again with Tom Anton, who is one of the top minds when it comes to the species' status and distribution in the area (and the state). First, we walked around a pond carpeted in duckweed that was chock-full of young bullfrogs (Lithobates catesbeiana) while looking for Northern water snakes (Nerodia sipedon). We then headed toward one of the areas where the Kirtland's snakes have been found. I noticed that the area in general contained perched wetlands, a component of the DRCA that I know Kirtland's snakes can be associated with. Numerous prairie crayfish burrows and chimneys dotted the mini-landscape. This locality was very small and provided hope that maybe there could be Kirtland's snakes at the DRCA, which is small itself but larger than this particular locality.
Next, Tom and I drove to an area off-site, where he had laid out cover boards over a decade ago. It had been a long time since he checked them, and so even finding them proved to be a minor challenge. But Tom is a human GPS and he found them in short order; together we ripped them up from under tall vegetation that had established itself in the intervening years since he was last here. No snakes were found. And so then we were off to another site located on FPDWC property where we hiked through very tall grass, saw a couple of Northern leopard frogs (Lithobates pipiens) and a single midland brown snake (Storeria dekayi). As the temperature rose to a sufficient level, we decided to road cruise a few back roads in the area. A few DOR Eastern garter snakes (Thamnophis sirtalis) were found, along with a single live specimen. It was a particularly attractive garter snake. A few more scattered snakes and frogs were observed, live and dead, including a fresh large DOR fox snake (Pantherophis vulpina) that was collected as a voucher, and a neonate of the same species found live on the crawl. Following lunch, we ended our day, both having collected some data and me with a better understanding of Clonophis.
A few final thoughts I had on the way home: What is to become of the Kirtland's snake? Will the species be around in 50 years? 100 years? How practical would it be to attempt a translocation of the species to suitable habitat in the region? Would a captive breeding program work for this species? How will population increase affect the snakes? These kinds of thoughts plague my mind all the time. Tom is confident that the Kirtland's snake is "doing okay" in the state. If anyone else assured me of that with any degree of confidence, I'd be critical of that perspective, but I do trust Tom's outlook. Still, I can't help think about how much we've reduced the species in the Chicago area, the state, and in its entire historic range altogether. We are content that most of the Kirtland's snakes in the state occur in protected areas, but is what's out there enough in the long term? All we can really do is try our best to right the wrongs we've committed, and that means to protect as much suitable habitat we can, make sure that land remains in good condition, and educate others about why these things are being done, and maybe help others understand why Clonophis is such an iconic symbol of our region's heritage.
The Kirtland's snake remained unseen, but this beautiful garter snake provided some excitement on the trip.
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