Shifting Baseline Syndrome

 John Cebula had a good point.

Many years ago, the retired college professor and amateur herpetologist would respond, in a somewhat discouraging manner, to field notes I had broadcast on social media.  At least that's how I saw it at the time.  I was committed to seeking reptiles and amphibians in the northwest corner of DuPage County and then share my findings.  If I had observed, for example, two fox snakes, two smooth green snakes, a milk snake, and a handful of common garters, I was on cloud nine.  But John's response was invariably a more sophisticated version of "that's cute".  He made sure to talk about all the herps he'd find back in the 80s while assisting Dan Ludwig & company with a county herp survey.

"Back in those days, we found smooth green snakes by the dozen.  I found a Blanding's turtle at the intersection of North Avenue and IL Rt. 59.  Fox snakes weren't uncommon as they are today."

Mentally, I dismissed these remarks.  John was a very nice guy, but really, with all of the natural areas around, how much could have really changed in nearly forty years?

Wisdom comes with time.  It would be years before I realized the fallacious nature of that old perspective I had been holding tight to.  Experience taught me that I had suffered a bad case of shifting baseline syndrome.

I mistakenly saw the 2017 landscape as THE baseline by which I gauged how well - or poor - nature was doing in suburbia.  That's the year I left the big city and settled in a semi-rural patch of suburbia 30 miles to the west.  The further west I drove on North Ave (IL. Rt. 64), the less developed the land was.  There were still some old homesteads, barns, and other features reminiscent of yesteryear and I just assumed that since they had been there this long, they're not going anywhere.

But since 2017, I've borne witness to big changes.  Some of the old homesteads had outstayed their welcome and were torn down to make room for detention basins and car washes.  Weedy lots that held a lot of biodiversity potential have been purchased and developed.  The southwest corner of Roosevelt Road and Winfield Road in Winfield, once a mature woodland directly across the street from Cantigny, was completely cleared to make room for a gas station.  It was clear to me that there was no such thing as permanence.  What originally appeared to me as a "finished piece" was in fact changing the whole time.  It made me wonder about the changes I wasn't aware of that had occurred in the area 5, 10, 20 years before.

Forty years ago, there were many, many acres of undeveloped land in my area.  In those days, John reveled in the richness of snake species and numbers, maybe so much that even he couldn't imagine a better time and place.  I enter the picture, working with what's available, and what I see as a good day would have been pathetic in John's day.  

When I read naturalist's accounts about the 19th century Illinois landscape, it is abundantly clear that we are living in a whole different era.  The ease at which Robert Kennicott procured Blanding's turtles in and around Glenview in the 1850s is remarkable (they are state-endangered today).  He found so many Graham's crayfish snakes within walking distance of his home that his pal Spencer Baird, at the Smithsonian, told him to stop sending specimens - he had more than enough.  And the Kirtland's snakes were probably everywhere nice, wet patches of prairie existed.  Kennicott of course is known for his discovery of the species in 1855 and likely didn't have to walk far from his home at the Grove to find it.   In 1892, Harrison Garman acknowledged the dramatic reduction of Kirtland's snakes in Illinois within his own lifetime.  He described the species as "formerly common in the north half of the State; rare at present" and added "A handsome snake, which ten years ago was not uncommon along prairie brooks...tiling, ditching, and cultivation of the soil have destroyed its haunts and nearly exterminated it."  Of course, in the decades since, with the implementation of mechanized agricultural practices, Kirtland's snakes are even more rare.  I'm confident I would have had a veritable field day counting Kirtland's snakes in 1892, and today a "good" population might occur on a scrap of habitat an acre in size and nowhere else beyond its artificial borders for many miles.

Entire landscapes have transformed into something unrecognizable, mostly due to human encroachment.  Most of the time, these are not good transformations.  H.S. Pepoon documented Chicago-area landscapes for his 1927 book "Flora of the Chicago Region".  These landscapes look almost pristine even though Europeans had been in the area for a century previous.  

Take this photograph, for example.  It is a view from Edgebrook Forest Preserve, located on the northwest side of Chicago.  It is beautiful. The caption states, "The trees are white ash".  Judging by the width of the path, these trees are mature and quite large.  Beside some (presumably native) shrubs, the woodland appears to be open and free of brush.  The lush herbaceous vegetation appears healthy; ample sunshine is reaching the duff layer.

I do not currently have an updated view available from this same or similar perspective, but I can assure you that these woods no longer look like this.  Most if not all of these ash trees are gone, victims of the emerald ash borer which has wreaked havoc on the regions' ashes.  In their places are mostly successional vegetation, including young green ash trees but also maples, buckthorn, honeysuckle, and various others.  Some large oaks remain alongside young oaks that have been planted in recent years.  The forest structure has undergone a substantial overhaul, and not for the better.

Now, check this out.  I took this photo at Rubio Woods south of 143rd Street back in 2014.  This is what a lot of the region's woodlands look like today.  A layperson might walk by this and feel a connection to nature.  It's green, it's lush.  The song of a raucous blue jay sounds from somewhere overhead.  All is good in the world.

But ecologists are screaming inside because there is lots wrong here.  I can go on and on about it (invasive species, fire suppression, etc etc) but my point is, little or no familiarity with what we consider to be our baseline for what a given ecosystem is supposed to look like can be dangerous.  

Henry Cowles was a pioneer ecologist who studied vegetative succession in the Chicago area

A skeptical college professor (from the same institution that had once had Dr. Robert Betz on staff, ironically) would ask, "From what period of the past should we be restoring land to?  A hundred years ago?  Two hundred?  A thousand?  THE ICE AGE??  Should we re-introduce wolves, bears, and mountain lions?"  A complicated problem to solve, actually.  No, we are well past the point of releasing large and potentially dangerous predators into our little scraps of greenspaces.  And no, we cannot change the trajectory of the Chicago River back to its original course (nor can we restore it back into a sluggish little stream).  No, we cannot bring back the Skokie Marsh, the Winnebago Swamp, or the Grand Kankakee Marsh.  Even our best efforts at restoring prairie create something of a shadow of the real thing; intact soil horizons and hydrology are key and these have too often been interrupted.  The simple answer to that question is, we can do the best we can - within reason - with what we know from history.

John Cebula's complaints over not not seeing enough snakes in 2025 doesn't mean he's bad at finding snakes.  It means he knows that once time, there were a lot more.  And that maybe one day, there won't be any at all.

History matters.