The water snakes of Lake Erie

As long as I've known about the Lake Erie watersnake (Nerodia sipedon insularum), I've been fascinated by them.  It's an oddball of a snake, currently restricted to about fifteen the Lake Erie Islands in the United States and Canada (eleven in the US and four in Canada; the snakes have been extirpated from a handful of islands.  A few other islands are very small and privately owned and therefore difficult to survey.  The total number of islands supporting the snakes in unknown).  In addition, the water snakes can be found along portions of the mainland's shorelines, south of the islands on the southern shores of the lake.  The "classic" Lake Erie watersnakes are grey or weakly-patterned, although some do display a pattern reminiscent of the more common Northern water snake (Nerodia sipedon sipedon) which is found throughout much of the eastern United States.  And just as in other species of Nerodia, these ones are just as irascible, biting and thrashing and musking when caught.  

The Lake Erie watersnake was once abundant throughout the islands.  French explorers referred to the islands as the "Islands of the Snakes" and noted that the snakes were "sunning themselves in heaps, knots, and snarls" by the thousands.  The gradual influx of settlers to the area coincided with a reduction in snake numbers as many snakes were killed by the hand of man.  Beginning in the late 19th century and especially through the 20th century, the islands witnessed an economic boom.  Logging, mining, and farming (and wine production) attracted boatloads of residents.  Later, some of the larger islands became tourist hubs, and still are today (the islands are key components of a portion of northern Ohio referred to as "Vacationland").  South Bass Island, an island with about 125 permanent residents, is host to over a quarter of a million tourists per year.

The surge of residents and visitors had a catastrophic effect on the Lake Erie watersnakes.  Numbers plummeted, and in the late 1990s the number of snakes fell to a mere 1500 adults. On August 30, 1999, the federal government listed the subspecies as threatened.  

Recovery efforts, headed up by the US Fish & Wildlife Service, were soon underway.  Research was conducted to help biologists better understand the snakes and their habitat.  Then, through a multifaceted approach combining habitat protection and public outreach, the numbers of Lake Erie watersnakes began to rebound.  Kristen Stanford, who began working with the snakes on the islands early on and who often went by the name "Snake Lady", became well known to locals.  When she was featured on an episode of Dirty Jobs alongside Mike Rowe, she garnered national acclaim.

But one of the key elements in the recovery of the Lake Erie watersnake had nothing to do with improving and protecting shorelines nor education.  An introduced, non-native species of fish, the round goby (Neogobius melanostomus), is perhaps the most influential factor in the watersnake's success story.  Introduced into the United States around 1990, this European fish had a profound ecological impact on the Great Lakes.  While displacing some species of native fish, the round goby became quite numerous.  As it turns out, Lake Erie watersnakes like them at least as much as the native species they previously preyed upon.  Therefore, the round gobies inadvertently bolstered the snake populations and continue to do so today.  Recent studies have shown that ninety percent of a Lake Erie watersnake's diet is comprised of round gobies.

As a result of the aforementioned conservation efforts and public outreach, Lake Erie watersnakes recovered well enough to warrant their removal from the Endangered Species Act in 2011.  Studies, primarily by Ohio State University's Stone Lab, are still conducted to this day, in an attempt to quantify the results of all of the measures that factored into the waternake's recovery, as well as to improve our understanding of the watersnake's natural history and ability to thrive in disturbed areas.

The Lake Erie watersnake first came to my attention in the mid-90s when I leaned about it in my Peterson field guide.  It was an intriguing curiosity, with its unique appearance and its tiny range, represented by hardly more than a dot on a map.  It dwelled in the back on my mind for a long time, until I had an opportunity to see them this past June while on a family trip to Kelley's Island (KI).

KI is one of the bigger islands in the group, and is touted as being the "quiet" island (especially compared to South Bass Island).  Though nearly the entire island has been clear cut, farmed, developed, or scarred through mining, there are still pockets of natural areas that support biodiversity.  Some of the remaining natural features are stunning.  Shoreline alvars support rare plants communities, an intact inland bay is reminiscent of the Florida Everglades, and an appropriately shaded woodland complete with ancient crumbling limestone harbors salamanders.  And of course the entire island's shoreline teems with watersnakes.  Little natural lakeshore remains, but the snakes have adapted very well to the riprap-lined shores and docks of the islands.  Interestingly enough, the vast majority of watersnakes seen were in Put-In Bay on South Bass Island during a day trip - they were abundant in the churning, turbid marinas and were even seen copulating within a stone's throw of idling catamarans and rowdy bars.  The watersnakes were also observed basking en masse among lakeside vegetation along Cedar Point Drive while we made our way to the amusement park for another day trip. 

This geologic feature known as the "Glacial Grooves" is actually a small remnant of a much larger series of grooves long lost to mining.  The grooves were gouged under the hulking glaciers that once shifted here.  This is a great outdoor classroom - it's only sad that most of what originally existed has been wiped clean, with a large hole left in its place (to the north and west).

After missing my first snake, an unusual inland watersnake on the crawl, the next one was easily captured as it basked among some large limestone boulders at the base of a jetty.  This is an Eastern gartersnake, Thamnophis sirtalis.

    Although the watersnakes can be found pretty much anywhere along the perimeter of the islands, they seem to like these rocky shorelines the best, at least on KI.  The rocks provide refuge and protection from predators and the elements while serving as great places to thermoregulate.

This was the first watersnake I caught on KI.  I spotted it as I traced the shoreline, walking along the top of the ridge.  It was moving quickly and nearly evaded me much like the first one did earlier that day.

 We visited this old quarry-turned-state park to try our hands at finding the state-endangered and federally-threatened lakeside daisy (Tetraneuris herbacea).  The lakeside daisy grows well on limestone and this site was chosen as an "insurance site" for the imperiled plant.  Though it was late in the season, we did manage to see a few daisies in bloom.

Of the jumping spiders we observed, this one was the most brilliantly colored.

When I heard American toads (Anaxyrus americanus) calling, I thought it seemed a bit late for that business.  In northeastern Illinois, they usually begin calling in late April and conclude around mid-May.  But here was a pair in amplexus (right side of photo, underwater) with eggs.

This is what I expected - American toad larvae.  We stopped counting at around 50,000 tadpoles, all hanging around in the shallow pools formed by rainwater.

A panoramic view of what was once lush forest and what is now a rocky desert.

The remains of an old car in the woods.

Very little quality woodland remains on the island.  This is a second-growth patch of woodland, littered with logs, limestone, and old bricks from long-gone buildings.  Eastern redback salamanders (Plethodon cinereus) hide under all of those things but seem to prefer the flat limestone.

Most of the redbacks we saw were of the "leadback" variety.

One of the few redbacks with a red back.  These little lungless salamanders are abundant in many of the areas they live.

The island's inland bay is a sight to behold.  Photos cannot do it justice.  The place was hopping with frogs.

Not all Lake Erie watersnakes ride the choppy waves of Lake Erie; this one was found basking in some branches under the canopy of the inland bay.  Here, it probably feasts on frogs more than fish.

One of two ambystomatids found near the bay.  I think it's a polyploid, a hybrid species drawing heavily from Ambystoma jeffersonanium - but I'm not really sure.  A beautiful little animal regardless.   

Back at the same jetty where earlier I found a garter snake, I found another.  Interestingly this one was near the tip of the jetty, a long way from soil.  I liked the red/orange color along the anterior of the snake's body.

While looking for watersnakes along said jetty, I met someone else who was doing the same thing.  Turns out he's a student with the Stone Lab, researching the snakes.  I agreed to hand over any snakes to him for processing.  It's sort of difficult to catch the snakes on a warm day along these huge boulders.  In order to catch a snake, you have to scramble down toward the water and risk twisting your ankle or worse, slipping on the slimy rocks near the water and twisting an ankle while falling into the water.  This fisherman (left) agreed to help spot snakes while we tried to grab them.  The snakes were quick and agile and repeatedly outwitted us.  Eventually we split up, and shortly after that I was able to catch one and give it to the young researcher.

This is the watersnake I caught that was taken to the lab to be processed before it was later released.  Notice the reduced pattern and lighter color compared to a typical northern watersnake.

One evening, while at the cabin where we stayed, it rained for a few hours, which really set the frogs off.  When the rain slowed to a drizzle, I grabbed my flashlight and headed out across the dark dirt road and into an empty lot where the rain had filled a pretty large depression in the ground.  The lot had previously been scraped of all vegetation in preparation to sell as a house or cabin site.  Clearly this site had been used as a fly dumping hotspot, and it was littered with old roofing material, lumber, drywall, rusty machine parts, and landscaping waste.  The owner of the cabin we stayed in told me it was just a matter of time before the site was purchased and developed.  The frogs that are found here will then be displaced.  This was one of the Cope's grey treefrogs (Hyla chrysoscelis) I photographed (and filmed) while it sang its heart out amongst partially submerged trash.

One of several calling chorus frogs (Pseudacris triseriata, or T. borealis, depending on which authority you subscribe to).

A portion of the lakeshore alvar located along the northern shore of KI.

On our final evening, while beachcombing and watching the gentle waves lap the pebbly shoreline, we noticed a medium-sized watersnake treading water about 20 yards out.  It appeared to be making its way toward land, but as I tracked its every move, it seemed to be tracking mine.  It began swimming parallel to the shoreline, moving away from the pebble beach and toward the alvar.  The water was decidedly rougher there, and after a few minutes of cat and mouse, I abandoned my plan to catch the snake out of concern for the animal.  Defeated, I returned to my wife and daughter empty-handed and resumed fossil hunting.  Maybe thirty minutes later, as we walked past the alvar to make our way up to the path leading into the woods, I spotted the snake out on the exposed limestone, exhausted and torpid.  After skillfully evading me earlier, now it seemed vulnerable as it laid there in a limp semi-coiled position.  I moved it a few feet away from where it crumpled, away from the churning waters of Lake Erie and onto some warmer rocks (I figured that since I likely played a part in its delayed beaching, I could interfere to its benefit).  Pictured is that very snake, a beautiful example of its subspecies, upon its ancestral rocks where countless others have basked for thousands of years.  With the sun setting behind us, the moment felt timeless.  I hoped this snake would live to reproduce and ensure that its kind would live on in perpetuity, in spite of man's ever-bearing presence.