Deer, Bears and Pigs: the Apples, Oranges and Pumpkins of Ecology

By Bob Ferris

 

In the mid-1980s I served as an ecological consultant for the University of California, Santa Cruz when they compiled their 20-year development plan.  I was making my living as a wildlife ecologist at that time and was excited by this departure from my normal set of consulting projects such as critter surveys for housing or energy developments.  I also was happy to be working both for my alma mater and on one of the wildest college campuses in America.  The campus at this point not only had live versions of UCSC’s banana slug mascot, but had habitats supporting coyotes, foxes, bobcats and an occasional mountain lion.  My job was to help keep these natural features and functions in the face of planned development.  

 

As I was writing my recommendations I received a phone call from a local reporter.  She kept asking me about deer: What was I going to do about the deer?  The 2001-acre UCSC campus is a little like a lop-sided bowtie with wildness at the top, open spaces at the bottom and a “knot” of development focused at the center.  In light of that I was most concerned about creating wildlife corridors that would allow predators to move freely from the upper campus to the lower to provide a biological counter-point to the burgeoning deer and ground squirrel populations.  

 

My frustration grew as the interview continued.  And, unfortunately, I had recently watched Woody Allen’s Stardust Memories and loved the line about pigeons being likened to hungry rats with wings.  Thinking that hyperbole would get us back to talking about fence design, light pollution, and dedicated vegetative corridors, I substituted deer for pigeons and earned one of my first memorable and controversial quotes as an ecologist. The episode taught me much about dealing with the press and educating the public about complex concepts and relationships.

 

Nearly a decade later in 1992 Jared Diamond wrote much more sensitively about the biodiversity tragedy unfolding in the Fontenelle forest near Omaha, Nebraska.  In his seminal article he asked the question on the minds of many in the conservation community: Must We Shoot Deer to Save Nature? (Natural History August 1992).  Now some at the time rightfully debated management approaches and methodologies, but the writing was on the wall in terms of ungulates in the absence of controlling factors degrading habitat for themselves and other species.

Over the intervening years these problems persist.  They linger and worsen largely because they are often very complicated and they call on society to make decisions and take actions that make many uncomfortable.  Moreover, the natural manifestation of the problems themselves are much like X-rays and CAT-scans in that the “fractures” and “tumors” are obvious to the trained and practiced eye, but little more than blurred images to others who might not understand, for example, the promise of migratory geese versus the peril of resident honkers. 

 

All of this comes to mind because my wife recently told me of an article about problem wildlife in Time magazine.  In the December 9, 2013 issue award-winning journalist David Von Drehle wrote an article called “America’s Pest Problem: Why the rules of hunting are about to change.”  I read Von Drehle’s piece and was happy that he raised many of these same issues once again.  But there were also parts of the article that I was bothered by.

 

 

My sense is that Von Drehle’s comments could have been more surgical in regards to apex predators, clearer in identifying comments about wild populations in wild places versus those in urban or suburban settings, and differentiating between native species and forms as opposed to those that are neither.  How so? First off his characterization that wolf populations are expanding so quickly that the US Fish and Wildlife Service (USFWS) is considering delisting the species, for instance, is problematic for anyone paying the least amount of attention.  A little research would show that wolf populations are declining in some areas, are not an urban or suburban issue because they have a low tolerance for humans and that the USFWS’s decision to propose delisting was driven more by wildlife commissions packed with agricultural interests and trophy hunters than by any population-driven imperative or crisis (please see peer review post).  

 

While we are on the topic of numbers, the piece also contains a quote from Dr. Maurice Hornocker that is a little sensational:  There may now be more mountain lions in the West than there were before European settlement.  Wow. That is a quote guaranteed to capture attention, but should it?  Right now elk populations in the West—in spite of protestations from chicken-little trophy hunters—are certainly near an all-time high and much higher than what was observed during the Lewis and Clark Expedition.  At the same time competing predator populations (i.e., wolves and grizzly bears) are seriously depressed hovering just above historic lows.  Then you take away 30-60 million migratory bison and throw in more than 20 million relatively stationary cows and a bunch of low IQ sheep and you have a recipe that results in more mountain lions.  

 

But all of this is more about the problems with predator control programs and public management of forests and grasslands than it is about exploding mountain lion populations near concentrations of humans.  Granted this quote by one of the foremost experts on mountain lions is true and there are issues with mountain lion populations near human settlements but mountain lions (panthers) are also an endangered species in Florida and missing from most of their historic habitats in the East.  My concern is that folks “reading” by looking at pictures and highlighted quotes might walk away from this piece thinking that a war on mountain lions in wild areas is justified when it is not (please also see blog about delisting peer review). 

 

 

Likewise the proffered argument about bullying grizzly bears driving black bears into settled areas seems almost silly in its insignificance and relevance in that there are so very few of these bigger bears in the lower 48 states and black bears are so readily and broadly recolonizing suburban habitats in the absence of their bigger, more aggressive cousins.  This is not to say that grizzly bears do not displace black bears and that there is not some readjustment taking place where recovering grizzly bears are reclaiming past haunts, but brown bear re-colonization happens at a relative snail’s pace so this is hardly in the nature of a black bear stampede.  

 

 

I also found the graphic on page 41 of the piece entitled “Beasts on the Rise” disturbingly simplistic to the point of being misleading.  Take the deer element of that graphic.  While some deer species in some areas such as white-tailed deer in suburban areas may be on the rise and a problem, other deer species including mule deer and black-tailed deer in the West are on the decline.  

 

Also these numbers themselves—out of context—are meaningless without addition information.  The fact that wolves have increased six-fold since the 1970s is interesting, but relatively pointless unless we understand what historic populations were or what current capacity for the species remains.  The 618% increase in wolves does not, in fact, support the article’s central thesis that wildlife are superabundant in certain urban and suburban areas and therefore additional management steps—including hunting—need  to be taken.  

 

While on the topic of “deer” it is interesting that elk were not covered in this piece.  Elk populations have gone from zero to 60 in a number of places through natural increase aided by habitat modification (e.g., timber cuts and fires) and aggressive reintroductions with significant impacts to agriculture, private property and human safety.  My sense is that most homeowners, farmers or drivers would much rather deal with a testy tom turkey occupying their backyards, visiting their fields or landing on their hoods than they would a bugling bull elk in the same circumstances.    

 

The piece and the page 41 graphic blur the lines in terms of native species and ecological function as well.  Wild pigs are not a native species and strike me as an entirely different issue than abundant or even superabundant native wildlife in urban and suburban settings.  In addition, wild pigs are not cousins to domestic pigs they are directly descended from domestic pigs that we released into the wild.

 

Moreover, while Canada geese have increased and are a problem in many areas, this is certainly not an issue of abundance or numbers, but rather one of behavior.  We have a shortage of migratory geese and an overabundance of resident geese that are polluting water systems and lowering the carrying capacity of wetlands by cropping aquatic vegetation at times and at levels that interfere with food supplies needed by migrating waterfowl during late fall and winter.  Here is where the informed lens sees peril in the US goose swimming in summer and that same heightened understanding prevents some from seeing the non-native, invasive mute swan as in any way equivalent to a migrating trumpeter swan.  

 

And beavers too.  The piece does beavers a disservice in terms of the ecological services they freely provide to characterize their increases solely as detrimental.  When we look at the drought-challenged West, restoring a critter that helps slow cascading water down on its rush to the sea so that it can sink down and recharge surface waters or even aquifers—while creating badly needed habitat for fish and waterfowl at the same time.  And as much as I like Microsoft folks, it seems of more value than some ornamental trees in Redmond.   That is not to say that I have never been angry when seeing a beaver-girdled tree in my backyard, but this is a case of making slight adjustments so that the much better benefit can be achieved across a larger landscape.  We do not live in Disneyland after all and we must take the good with the bad.

 

Now I have heaped a lot of criticism on this piece, but I am also glad that it was written.  I am glad, because we must talk and think about these issues.  Good and bad articles in this context become teachable moments in a world badly in need of teaching.  In recognition of this, we all need to recommit ourselves to education and not view environmental education, science and math as expendable as some view these important species.