cc  >> Nadia Dominguez: Welcome to  Wednesday Nite at the Lab  at the UW-Madison  Biotechnology Center.  Tonight we welcome  Dr. Don Waller of the Department  of Botany here at the  UW-Madison.  Dr. Waller is an ecologist  in the Department of  Botany here at the UW.  He teaches courses in ecology,  evolution and  conservation biology.  His educational background and  training spans several  institutions and fields.  He received an AB in biology  from Amherst College  and a PhD from Princeton  University in biology  and population biology.  He received post-doctoral  training from Harvard  University.  He has also authored and  coauthored over a hundred  journal articles, as well as  nearly 20 book chapters.  He's also coauthored a book  titled "Wild Forests:  Conservation Biology and Public  Policy."  He has also recently co-edited  yet another book.  And he has worked with numerous  state and federal... 

 There we go.  Here is his recent, in 2008,  he co-edited  "The Vanishing Present."  Is that correct?  >> Yes.  >> All right.  He has worked with numerous  state and federal agencies and  environmental organizations that  his work has impacted both  forest as well as game  management.  He also holds many prestigious  roles and positions.  He is a fellow of the American  Association for the Advancement  of Science, a former editor in  chief of the journal Evolution  and former president of the  Society for the Study of  Evolution.  He also told me, I talked to him  briefly beforehand, one very  interesting and fun fact that I  think is related to his topic  today, he recently took up  bow hunting, actually recently  meaning four years ago he took  up bow hunting.  So tonight's seminar will  highlight the economical and  ecological impacts of high  deer populations.  So please join me in welcoming  Dr. Don Waller to Wednesday Nite  at the Lab.  [APPLAUSE]  >> Don Waller: Thank you, Nadia. 

 And a pleasure to be here.  And so many coming out on 12th  night to hear a talk on deer.  Of course, deer are very popular  in Wisconsin, and in fact across  the country.  And they're popular for  different reasons.  But I want to get into, also,  the issues associated with their  popularity and their current  abundance.  On the one hand we look upon  whitetail deer as blessed from  on high, and this card from the  Missouri botanical garden, the  character from childhood stories  were all familiar with like  Bambi.  The most popular game animal and  the source for licensing revenue  for the Wisconsin DNR and other  state agencies.  The only large mammal most of us  are likely to see at all  commonly in the wild.  And a very popular animal to  watch and to feed.  On the other hand, we also  associate whitetail deer now  with a number of problems. 

 Issues like disease risks,  expansions in the incidence of  Lyme Disease carried by this  deer tick, bovine tuberculosis  which has broken out in the  lower peninsula of Michigan, and  of course Chronic Wasting  Disease which has broken out  here in southern Wisconsin and  has resisted all attempts to try  and contain it these past eight  years.  In particular, this shows a map  of where Chronic Wasting Disease  is.  Now the initial outbreak was  just west of Madison but as you  can see now it's expanding down  into Illinois.  And this Chronic Wasting Disease  zone tends to keep expanding  despite efforts by the DNR to  step up hunting, and to try and  reduce the deer herd in that  area.  In fact, deer densities remain  at close to 35 per square mile  in that area which is one of the  contributors to the spread of  that disease.  We also know that deer cause  many collisions on the state  highways.  This is not an occasional or  rare thing.  In fact, it happens somewhere  between 30,000 and 40,000 times  each year in both Michigan and  Wisconsin and numbers a bit  below that in many other states.  One in 39 drives is likely to  hit a deer in West Virginia.  One in 230 Illinois drivers hit  a deer this year because of most  of them are driving around  downtown Chicago, I assume. 

 [LAUGHTER]  What I'd like to speak with you  about tonight is a bit  of ecological history  to start with.  How did we get into the  situation that we're in.  As an ecologist I have become  more and more aware of the  importance of history, and as  well as our need to understand  things that occur at larger  scales over longer time periods.  After discussing shifts in  landscapes that are associated  with colonization and use of the  landscape by European settlers  in the late 19th and early 20th  century, we'll talk about shifts  in predator populations and the  ungulates, that's another word  for deer and their relatives,  and shifts in hunting  regulations that have led to our  current situation.  And then I'll discuss research  I've done over the last 15 or 20  years assessing the ecological  impacts of deer.  And it turns out there are  several different ways of doing  this and I think I've tried them  all one way or another.  I've looked at forestry  regeneration, we've looked at  patterns of plant diversity,  we've looked at exclosures,  we've looked at regional  comparisons, and this is giving  us a fuller picture of what the  ecological role is of this  keystone herbivore.  But the question I want to  emphasize and that I want to  leave you with tonight is can we  manage forests and wildlife  together as a system?  Because they're intimately bound  up with one another even though  we tend to think of them in  isolation from each other.  So let's start by taking a look  at the north woods.  This is a nice spot along the  Brunsweiler River in northern  Wisconsin not too far from  Mellen. 

 It's a landscape that looks a  lot different now than it did 80  years ago when it was acquired,  by the Hanson family as it turns  out.  And it was so cut over and ugly  looking that many people  questioned why anyone would want  to buy the land.  Of course another hundred years  before that and it would have  been an even more mature forest  than what we see here.  The original forest that existed  across northern Wisconsin, and  in fact much of the north  eastern United States, was  predominately an old growth  forest.  It was a forest dominated by big  old trees.  It's a forest that had trees  living a hundred, 200, up to  more than 400 years old.  It was a forest that was  primarily in steady state with  small scale disturbance.  The canopy was more or less  intact.  The natural death that opened up  patches in the woods were often  signal tree falls or groups of  trees falling over in response  to windfall, ice storms and so  forth.  Here's a botanist for scale. 

 In one of the very few of these  old growth forests that we have  left in Wisconsin.  This one's on outer island in  the Apostle Islands on Lake  Superior.  Emmett is the director of the  herbarium at UW Stevens Point.  And you can see that a big tree  going down like this makes a big  opening and a lot of soil  disturbance that provide  opportunities for other trees to  colonize and regrow in that gap  once the light gets in.  Interestingly, many of the trees  that lived in this old growth  forest were specialized for the  conditions that existed there.  In particular, they had  seedlings that benefited from  the coarse, woody debris.  The downed logs and big branches  that would occupy maybe 5% of  the forest floor but often have  upwards of 60% or 80% of the  seedlings of yellow birches and  hemlocks and other lake  successional, shade-tolerant  trees on them.  We call those nurse logs.  Sometimes disturbances occurred  at a larger scale, of course.  In areas with sandy soil  dominated by the pines, we  tended to have fires recur at  regular intervals. 

 In the more mesic forest that  I'm talking about mostly, it  would be larger scale wind  storms that would open up bigger  gaps in the canopy.  Like this one shown at Kemp  Station in Vilas County from  about eight or ten years ago.  Typically, these larger gaps  would be occupied by the  shade-intolerant, early  successional trees like aspen  and birch that have small wind  blown seeds that are excellent  at colonizing those sights and  can grow quickly.  But it's been estimated by  Charles -- that no more than  about 15% to 25% of the  landscape at any given time were  in these earlier successional  phases.  Most of them were that mature  old growth forest I had talked  about before.  At that time, it was a landscape  not just of big trees but it was  a landscape of big animals as  well.  The big animals included not  just whitetail deer but, in  fact, a whole guild or suite of  large ungulates including elk,  primarily in the southern  savannas and prairies; moose,  especially favoring in wetlands;  woodland caribou were in  Wisconsin; and deer probably at  a density that's estimated at  four to eight or maybe five to  10 deer per square mile.  We also, of course, had large  predators at that time.  The big cats like cougar and the  big dogs like wolves and  wolverines.  Wolverines have been extinct in  the wolverine state and the  state of Wisconsin through most  of the 20th century. 

 And cougar, likewise, are not  considered to be present,  although occasional tantalizing  glimpses or photographs even of  them have turned up.  There was a cougar that I think  was tracked into suburban  Chicago a few years ago before  it was shot by a policeman.  Great wolves are a success story  here in Wisconsin.  Although they were exterminated  by bounties by the mid-20th  century, they recolonized on  their own and from Minnesota  starting in the early 1980s, and  now number a bit over 600  animals.  Of course, what brought the  European settlers to the upper  Midwest during the Paul Bunyan  area were the giant trees,  especially the large softwoods,  the big white pines, that they  could float on the rivers down  to their sawmills that supported  the growth of agricultural in  cities here in the Midwest.  A very well-told story by my  colleague Bill Cronon in his  Nature's Metropolis book about  the growth of Chicago.  There were connections, of  course, between those growing  cities and farms of the Midwest  and the north woods.  The cheap land meant that a lot  of the loggers moved into this  area, cut the very largest, best  trees out as quickly as they  could, and then often simply  skipped town rather than pay  taxes on their land or attempt  revegetate.  George Weyerhaeuser got a start  here but ended up in the Pacific  northwest, for example.  Of course loggers do a lot of  hard work, and that makes them  hungry and they filled the pot  in those logging camps often  with local wild game which  included, of course, whitetail  deer. 

 But it was also an era of market  hunting, in the 19th century I'm  discussing now, where you can go  out and shoot a lot of animals  and ship the meat into the  cities and make money.  Probably the railroads and the  telegraph spell the end of the  passenger pigeon which were  ecologically extinct in the wild  by the year 1900.  But at any rate, the loss of so  many huge forests in such a  relatively brief period of time,  really just one or one and a  half generations, in the late  19th century and the decimation  of game heard herds, of bison  and elk and the demise of the  passenger pigeon I think did a  good job of waking many people  up in the United States to the  dangers of over-exploitation of  natural resources.  So we saw calls to establish the  forest preserves in the 1880s  and 1890s, what became our  national forests.  We saw the establishment of our  first national parks with  Yellowstone and others  following.  And we saw in particular at the  turn of the century, effective  laws to protect wildlife.  The landscape will look  something like this at the time  of the great cut-over.  After the large softwoods have  been cut out and floated down  the rivers to the sawmills,  railroads were punched through  allowing them to cut first the  hemlock for the tanning trade,  eventually the hardwoods as  well.  And at that point the land was  clear cut.  It was also the time of the  great fires like the Peshtigo  fire of 1873 that burned over,  what is it, parts of a couple of  counties, killed more than 1400  people. 

 It occurred on the same day of  the great Chicago fire so we  don't tend to hear as much about  it.  But a scene of incredible  devastation.  In some places, I've seen in  sand plains in the upper  peninsula of Michigan where no  trees have been able to grow  back since then because the  intensity of the fire was so  great that they burned through  all the organic layer, and  there's not enough nutrients  left.  But in most of the landscape  things weren't quite so dire,  and the Civilian Conservation  Corps and other groups moved in  in the early 20th century to  revegetate the land.  We had county forests and state  forests established on some of  those tax-default lands.  We saw the CCC planting  especially red pine plantations  for the timber trade.  And much of the timber interest  in the Fox River Valley and  north of there turned to aspen  because aspen was one of the  predominant trees to recolonize  that devastated landscape.  It's a premiere colonizing  species.  Wind blown seeds.  It moves in quickly after fire  or clear cutting. 

 It grows quickly.  It can be harvested at an early  age for paper pulp.  And so a lot of our paper  industry now, and we are the  paper basket for the nation,  depends on this aspen forest  type that now grows over much of  northern Wisconsin.  In addition, those wildlife  protection laws established  prohibitions against shooting  migratory birds and strict  hunting regulations involving  limited hunting seasons, bag  limits, favoring bucks over does  and so forth.  So to summarize, we had a time  of cataclysmic ecological change  in the late 19th and early 20th  century where we went from a  mostly old growth matrix with a  continuous canopy dominated by  maple, hemlock and yellow birch  with some red and white pines  and oaks mixed in, to a very  different landscape.  It was, in a sense, inverted.  It was turned inside out.  Now the landscape and most of  northern Wisconsin and the UP  consist of early successional  aspen and birch.  Old growth forests are down to a  percent or two of the landscape  instead, islands in an early  successional ocean, if you will.  And we've replaced wind throw  and ice storms and occasional  fires by logging as the  predominant disturbance in the  north woods. 

 Logging and this satellite  photograph in the Ottawa  National Forest is typically  done with scattered clear cuts  which tends to maximize the  amount of edge in early  successional habitat in the  landscape.  This has profound ecological  results the conservation  biologists spent much of the  late 20th century trying to  understand.  So with this inversion, we went  from mostly old growth and few  early successional trees to  mostly early successional trees  and very little old growth.  So what are the implications of  that landscape change for the  wildlife populations?  It was Aldo Leopold who taught  that the way to manage game is  to manage habitat.  And that meant, of course, that  you could manipulate vegetation  and favor particular favored  game species.  He was also the first one to  discover what was referred to as  the edge effect, the positive  effects of edge habitat on  popular game species like  whitetail deer and grouse and  other fast growing herbivores.  Keith McCaffery of the Wisconsin  DNR created this graph some  years ago showing that the more  you have of aspen or early  successional trees in an  environment and the more  openings you have in edge  habitat, the more deer you can  expect in a given township.  If you're not into  three-dimensional scientific  graphs, you can go into Nick's  Family Restaurant in Spooner,  Wisconsin, and get exactly the  same message in a more simple  form in terms of the place mats  there.  Early successional aspen,  openings, grass, lots of  whitetail deer.  We have other reasons why  whitetail deer have become more  abundant. 

 I mentioned the absence of  predators already.  In addition we do have conifer  stands that still provide deer  yards in winter.  And we now have a very popular  pastime across much of northern  Wisconsin, as you'll see in any  convenience store or gas  station, the bags of deer food  that they have stacked up.  So what I'm painting for you  here is a picture of a changed  landscape with a changed set of  animals.  We've got mostly old growth  where most of the green foliage  to eat was up high.   Deer are not giraffes, although  I've seen them standing on their  hind legs to reach up as high as  they can to eat foliage.  So when they have a situation  with continuous dense forest  cover, they don't have a lot to  eat, their densities are fairly  low, also because of their  predators which included  American Indians of course  before European settlement and  then Europeans after that, what  that meant was that deer impacts  tended to be relatively limited.  Again, a fairly low deer density  through most of the landscape.  After most of the big old forest  was cut down and you had that  proliferation of openings and  edge, you got superb positive  habitat conditions favoring an  explosion of the deer herd.  Once game seasons effectively  restricted the take, once we had  a hunting ethos that emphasized  the shooting of bucks instead of  does, especially in the '80s and  '90s you started to see more and  more feeding in northern  Wisconsin, we got a situation  where deer populations  multiplied and have stayed now  at chronically high levels for  several decades. 

 And so this led me to the path  of research that I want to  describe next.  What are the impact of having so  many deer on the landscape, on  the plants that they ultimately  depend on, the regenerating tree  seedlings and understory plants  in general?  Before I go there though, just a  reminder, we had this suite of  large cats and dogs, predators  and large ungulates and now  we're left with a very different  system.  Essentially one predator limited  in its population to a few  hundred, a deer herd of between  1.4 and 1.7 million in the  state of Wisconsin.  And it's that situation that  needs studying.  Deer populations climbed through  much of the 1960s and '70s in  response to those favorable  habitat conditions and the  absence of predators.  Deer that used to be below eight  or 10 deer per square mile are  at 60 deer per square mile on  Madeline Island.  They're at 45 deer per square  mile at many parts of Wisconsin.  They're at 35 deer per square  mile, as I mentioned, west of  Madison in the Chronic Wasting  Disease zone.  They're closer to 15 deer per  square mile in parts of far  northern Wisconsin near the Lake  Superior snowbelt and now in  northeastern Wisconsin in the  last year or two.  As you see from these numbers in  Michigan, one reasons that deer  numbers are high is that hunters  have absorbed the lessons of  their grandfathers to shoot  bucks and not to shoot does. 

 That was originally, of course,  intended to replace subsistence  hunting and market hunting with  sport hunting.  It was considered more sporting  not to interfere with  reproduction of the herd by  shooting does.  There was an emphasize on  shooting a buck with a large  rack of antlers.  There's a Boone and Crockett  scoring system.  Hunters salivate this stuff now.  If you go into a bar in northern  Wisconsin and want to play the  big buck video game, you get  lots of points for shooting big  bucks, but if you shoot a doe,  your score goes down.  And there are all kinds of  messages right now emphasizing  in tendency to shoot male  animals instead of female  animals.  And this has put the DNR into a  bind.  Hunters and the Wisconsin DNR  exist, whether they like it or  not, in an intimate symbiosis.  The DNR manages the deer herd. 

 Their primary management tool is  hunters.  Each side depends on the other.  Hunter numbers have been static  in Wisconsin and declining in  most other parts of the country,  however.  And we've seen, as I said, a big  increase in deer herds across  many areas.  Deer are now chronically over  the target goal density in many  deer management units throughout  the state of the Wisconsin.  In fact, in most deer management  units.  I made this graph a couple of  years ago, and I know deer  numbers are down in the last  year or two, but you can see  it's that chronically high deer  population that led the DNR to  implement many of their recent  policies including bonus tags  and extra antler list permits  and eventually the Earn-a-Buck  system which they used as a tool  of last resort.  So Chronic Wasting Disease  presented them with a huge  management challenge in southern  Wisconsin.  If we have prion disease in the  deer herd, many hunters are less  inclined to hunt, worried about  possible human health affects.  This, in turn, reduces hunter  effort exactly at a time and a  place when the DNR is attempting  to step up the intensity of  hunting. 

 So you've got some real issues  here.  So let's turn to the ecology  side of things.  How do we assess deer impacts?  There are several different  approaches.  The one that predominates,  historically and in fact in many  of the discussions today, are  anecdotes.  I'm not against anecdotes.  They have a lot to recommend  and, in fact, I'm trying to  organize a deer monitoring  consortium right now that would  ask hunters to report how many  deer they've seen, where they've  seen them and what impacts  they've noticed on understory  plants.  But that's not the only way to  look at deer impacts.  As a scientist, we have a lot of  other tools in our tool kit and  we can use these.  We can use natural experiments.  We can compare areas like  islands that have more or fewer  deer or no deer at all. 

 We can compare parts of the  landscape, regions that have  high deer densities like many of  the forest public lands, and we  can compare those with areas  that we know have lower deer  densities like several of the  Indian reservations in the state  of Wisconsin.  We can use experiments.  We can build fences in the woods  and keep the deer out or stock  an area with a given density of  deer.  This is a good way to get good  information.  And we can also look at long  term shifts or changes in the  composition, in the demography  or age structure of trees or in  the abundance and diversity of  the understory plants.  So this is what I'm going to  talk about next.  So anecdotes.  I'm sure all of you who've paid  attention when you've traveled  in northern Wisconsin or the  upper peninsula or elsewhere,  have noticed things like a  conspicuous browse line on these  northern white cedar trees here.  Or you may have noticed a  sandwich tree next to my former  student Tom Rooney here that has  a lot of foliage up high and  some good foliage down low and  nothing in between.  Now that's because snow tends to  be about three feet deep or four  feet deep in the wintertime in  many parts of northern  Wisconsin, protecting that  foliage down there. 

 And deer, like I said, haven't  become giraffes yet to stretch  up too high.  But there's this molar zone in  between where foliage is very  vulnerable.  We can also look at the  condition of deer yards.  And the DNR has been doing this  for many decades.  The good thing about anecdotes  is that it's a completely  democratic process.  Everyone can participate,  everyone has their own favorite  stories, their own observations.  They did or did not see any  bucks or other deer during their  sit on a deer stand in this past  gun season.  Or they've noticed that the deer  that used to be abundant are  more dispersed now or they  seemed to have moved somewhere  else.  However, the problem with  anecdotes is that they're  anecdotal.  They're often a very sample  size, the end of one problem. 

 They're unsystematic, they're  often unverified.  People see different things at  different times and places.  They leave room for argument.  It's not systematic enough to  satisfy the criteria that most  scientists have.  We need to systematize and  collect more of those anecdotes  to really make them more useful.  So let's talk about how we can  study deer impacts by looking at  islands.  This, by the way, has been  studied not just here in  Wisconsin and the Apostles, but  it's also been studied in Haida  Gwaii, the Queen Charlotte  Islands off the coast of British  Columbia where there has been  first rate work on the impacts  of introduced -- blacktail deer  on the understory plant  communities there and on trees.  They have a white cedar very  closely related to our own, in  the same genus.  It's been decimated on Haida  Gwaii.  But I'll talk about my own  results here. 

 We've noticed in comparing  islands that have deer to  islands that do not have deer,  that we've seen a big decline  particularly in Canada yew, taxa  canadensis, striped maple,  yellow birch, mountain ash, the  blue bead lily clintonia and  wild sarsaparilla aralia.  These are all species that are  conspicuously lower in abundance  on islands with deer than on  islands without deer which are  otherwise similar.  So we're pretty sure that's a  deer signal that we're picking  up.  In addition, and this is the  most interesting part of the  finding for me, if you ask which  species are present and what  their abundance relates to, it  turns out that deer abundance in  the 1950s and '60s predicts the  abundance of these species  better than the abundance of  deer in the 1980s and '90s.  Implying, to me anyway, that on  these islands the impacts that  deer at 40 or 50 years are  persisting for many decades, and  there hasn't been enough time  yet for recolonization or  reestablishment.  That is, we have some islands  where deer have recolonized  after going extinct and other  islands where the deer have been  driven off or gone extinct more  recently.  The Ojibwa word for Canada yew  means that which grows  everywhere.  Canada yew is a conifer.  It's sometimes called ground  hemlock.  It was so ubiquitous in the  landscape that the Ojibwa were  tripping over it all the time. 

 It was an impediment to move  around.  If you look for Canada yew now  in northern Wisconsin, I predict  most of you will have a hard  time finding it.  It's become rather scarce.  It's become vanishingly scarce  or completely absent in areas of  whole counties, in fact.  And this particular population  on Raspberry Island, where I've  heard you can walk across it in  snow shoes, exists there because  that island is free of deer.  Likewise, you see it in the Lake  Superior snowbelt, you see it on  cliffs, you see it sometimes  along roads where deer don't  tend to browse quite as  commonly.  Let's look at hemlock.  This particular exclosure in the  -- creek area of the Chequamegon  National forest was established  back in the 1950s, I believe,  and you'll notice, I won't have  to tell you which side of the  fence is inside and which side  of the fence is outside.  Exclosures like this are very  informative.  They tell us what might be  possible if deer weren't chewing  down the tree seedlings all the  time. 

 This particular exclosure, when  I showed it to some colleagues  in the DNR in the early '90s to  plead for lower target deer  densities, said, well, you can't  make anything of that because  everyone knows that exclosure  was built in a deer yard.  We would expect deer impacts to  be large in areas where deer  tend to yard up in the winter.  They congregate under coniferous  trees because they have some  thermal cover, they don't  radiate as much heat to space  and especially because there's  less snow under those conifer  trees so they can move around  more easily, as well as the fact  that they eat author conifers in  the wintertime.  So eastern hemlock is a slow  growing, late successional tree.  As you've already learned, it  was once a co-dominant over much  of northern Wisconsin.  Regeneration of this tree is now  becoming problematic.  It's a serious issue.  People are not finding the young  hemlock seedlings and saplings  that they would expect to.  So we began exclosure work.  This is my colleague Bill  Alverson, now at the Field  Museum, putting up one of these  exclosures in the Lac du  Flambeau Indian reservation. 

 We planted, in fact, a couple of  dozen of these hemlock seedlings  in two patches.  Then we'd flip a coin and put  the fence down on top of one of  the two patches.  And then we've come back every  five or six years since to find  out, not surprisingly, that the  ones inside the fences are  growing fine.  It's not something with the  soil, it's not the climate, we  have conditions that would allow  hemlock to regenerate, but the  ones outside are being browsed,  in general, at a rate that's  proportional to the number of  deer piles we find in the  vicinity.  And they're dying, of course, at  a higher rate too.  Exclosures in the Dairymen's  Club near Boulder Junction in  Vilas County was enough to  convince them that they had a  serious problem with deer.  They had, essentially, a  grassier sedgy area outside.  And you can see that dense  regeneration they got inside.  After prohibiting deer hunting  for a period of 30 or 35 years,  the Dairymen's Club actually did  an astute about-face and began  hunting in earnest, recognizing  that they were going to lose  their forest if they didn't do  something about it.  Research we had done there also  indicated that Piney Point there  had lost half of its original  understory plant diversity in 50  years, primarily in response to  deer browse. 

 So exclosures are in some ways  the gold standard, but they have  the disadvantage of being an  extreme comparison.  You got a lot of deer outside,  you've got zero deer inside,  typically.  They're also very local and they  tend to be expensive to  construct and maintain.  So a lot of people get excited  by building an exclosure, and  then they don't do a lot of good  work to maintain it.  So another approach we've taken  is looking at these regional  patterns.  A little bit like that natural  experiment on islands, but here  you're just using the regional  landscape variation in deer  abundance.  So here is Tom again standing  near a nice patch of  regenerating hemlock.  It gets some nice side light  near Star Lake.  A hemlock hardwood stand near  --.  But in many areas you see  hemlock seedlings that are  getting so heavily browsed they  can't possibly make it. 

 They're slow growing.  They can't tolerate more than  one or two bouts of browsing  before they're dead.  You just get a skeleton.  So we studied hemlock  regeneration at 142 sites spread  over the landscape.  We included Indian reservations  and the islands to give us  variation.  Right away we noticed from our  sugar maple index, counting the  number of twigs on sugar maple  that were browsed or intact,  that there were big differences  between the Lac du Flambeau and  Menominee and Lac Courte  Oreilles Indian reservations and  the Apostle Islands over here  and what we were seeing in those  other public land bases, which  typically had 40% or 50% of  their twigs getting browsed off.  Likewise, we saw a strong  connection, correlation, between  the mean number of hemlock  saplings we saw and our index of  summer browsing on sugar maples.  Most of the hemlock browse  occurs in winter versus the  summer browse on sugar maple.  But this is a pretty tight  relationship.  Again, very strong evidence that  deer are having a major affect  on this particular tree species. 

 We also did demographic models  where we looked at the  recruitment of seedlings into  small saplings and larger  saplings and discovered that  even though light and soil  conditions could strongly affect  the initial abundance of  seedlings at a site, that it was  deer browse that was the only  factor or the predominant factor  affecting survivorship to those  larger size classes.  We did similar work on northern  white cedar.  Like hemlock, this is a  slow-growing tree that's a  favored deer food.  Very susceptible to browse.  Also it's home to some of the  state's rarest plants like this  ram's-head lady's-slipper.  And you don't have to do a fancy  statistical model to realize  that this demographic profile on  the Nicolet and Chequamegon  National Forest is quite  different from the demographic  profile on the adjacent Indian  reservations.  There's some fundamentally  different going on in areas  where you have high and low deer  densities, as you do there.  This particular shot is the  Sylvania Tract.  Initially I'd assume if you had  an old growth forest that was  large enough in extent, that  that would naturally bring down  the deer densities because there  would be less for them to forage  on compared to those early  successional edgy patchy  habitats.  The Sylvania Tract, at 15,000  acres, appears not to be large  enough for any such effect to be  present. 

 In fact, deer tend to congregate  in this area because of the good  conifer cover in the wintertime.  Great place to ski and canoe, by  the way.  Again, you don't need fancy  statistical models to recognize  when your forest that used to  look like this has become a  somewhat different place.  Things like this have been  reported over and over again in  many regions around the Midwest  and across the northeastern  United States.  Trillium is kind of a nice  example.  It's a member of the group, the  Liliaceae, the lilies, that tend  be favored as deer food, they're  palatable to deer along with  lobeliads and orchids.  Some of our favorite understory  wildflowers are, in fact, also  popular among deer.  That showy white flower also  acts probably as a flag to  attract the attention of deer,  let them know where they are.  So some people have suggested  that we could use yew or lily as  indicator species, and we can  monitor the abundance or the  height or the number of flowers  we see on these species to track  how many deer there are in an  area or what their impacts are.  It has a lot of advantages. 

 It's quantitative, it's a very  simple approach.  My dream again is to establish a  deer monitoring network across  the state of Wisconsin where we  ask high school and even middle  school teachers and students to  plant trilliums or orchids or  tree seedlings in their school  forest or another nearby patch  of woods, and they can track  that over time and they can  record and share with others the  information about how many of  them are surviving and or  whether those patches are  growing.  I think we have a lot of  potential to do important work  at a relatively low cost.  The disadvantages of using  indicator species is that  because browsing is so patchy,  individual animals browse one  patch and not another, you need  a big sample size.  You need a lot of people looking  in the woods at once to go  beyond anecdotes to make this  useful scientific information.  You're also looking mostly at  summer browse on trillium; you  actually could look at winter  browse on yew if you wanted to.  And it's also true that each  species is only really useful  over certain deer densities.  And that's because yew and  trillium disappear once deer  have been over 15 or 20 deer per  square mile for a few years.  So I want to bounce back now to  the bigger picture again.  I've shown you a variety of  evidence of different kinds to  support this idea that deer are  having impacts in the woods. 

 I've shown you browse seedlings.  When we began this research, we  focused on hemlock and white  cedar, knowing them to be  susceptible to deer browse and  they were slow-growing.  We thought they'd be slow to  recover.  The surprise for us in doing  that field work was to discover  that red oak, yellow birch,  sugar maple and even balsam fir  are being strongly affected in  many areas by deer browsing now.  Balsam fir, in particular, is  considered a poor food for.  They only eat it as sort of a  last resort.  It doesn't support good growth  of deer.  And yet it is being heavily  browsed in some areas.  An indication that deer are at  or beyond their caring capacity  in many areas, and we may be  facing fawn starvation in the  woods in parts of northern  Wisconsin except for the fact  that they're all being fed in  backyards, that is.  Aldo Leopold said, I love all  trees but I am in love with  pines. 

 And that's why he planted all  those ones next to his shack  near the Wisconsin River, most  of which died in the drought  following after that.  But if you go to the north  woods, these giant white pines  that were so abundant once that  they brought all those Paul  Bunyan loggers into the region  have now become so scarce, the  big old ones, that they get  individual titles.  Let me introduce you to the  General Sherman white pine.  People revere these huge trees.  The white pine used to grow up  to six or eight feet in  diameter.  Up to 200 feet or more in  height.  It was the redwoods of the  eastern and Midwestern United  States.  But now if you ask where the  next generation of white pines  is, you look at these as kind of  punk-haired teenagers, they've  got a little bit of foliage, a  tuft maybe on top, but they're  bereft of foliage lower down.  They're already on their way to  becoming a sandwich tree.  Again, we've got indications of  deer having a big impact on the  regeneration of white pine. 

 The last technique and approach  that I'll describe to you  tonight is to look at the whole  understory forest community and  ask how is that changing over  longer periods of time.  This has a lot to recommend it  to.  If we look at all the species  that are present we don't have  to worry about the disappearance  of one or two or three species  that are highly palatable and  favored by deer.  We can look at what are called  community indicators.  We can look at overall species  diversity and overall density of  plants.  We can look at whether the  communities are becoming more  similar to one another, what's  sometimes are referred to as  biotic homogenization, and we  can look at patterns of relative  abundance of the deer sensitive  to the deer resistance species.  And then we compare all these  things to some kind of baseline.  We can look at an Indian  reservation or we can look at  these same forest communities,  if we had the data, from say 50  or a hundred years ago.  And then we can ask are the  sensitive species, the ones that  are declining in abundance and  disappearing, does that give us  a signature of deer impacts.  The problem with working with  understory or basis vegetation  is there's no woody structure. 

 If all the tree seedlings  disappear, I still know there's  a standing white pine or a bunch  of hemlocks in the canopy.  I can still figure there should  be seedlings so I can get down  on my hands and knees and look  for those tiny seedlings.  But if an herbaceous species  disappears, there's sort of no  history there.  We don't know if it was there  previously or not unless we have  a baseline.  So we need a baseline and we  need monitoring to figure out  what's going on in the woods,  and this is where I'm doing a  will the of my current research  right now.  My colleague John Magnuson in  the limnology section here at  the University of Wisconsin has  written movingly about what he  refers to as the invisible  present.  He's concerned about the  ecological changes that are  going on all around us but are  occurring just slowly enough for  most of us not to notice.  They take longer than the three  to five years of an average PhD  project or -- studied research  grant.  They occur over a period of  decades maybe or a century or  two.  We can't use paleontology, it's  not that old yet. 

 But this slow-moving catastrophe  that we see right now in terms  of the demise of biological  diversity is exactly what  Magnuson's referring to here as  the invisible present.  And that, of course, was also  the reason I stole the idea for  the title of the Vanishing  Present where we tried to  collect together a few of these  tales to lift the veil on the  vanishing present to see what's  really going on.  Our own particular chapter in  this book is about what's going  on in the woods.  I'll just talk about the north  woods here.  John Curtis, a famous Wisconsin  plant ecologist and the author  of the Vegetation of Wisconsin  book, fanned out across the  state and surveyed sites with  his students over a period of  1948 until about '58 or '59 when  he died.  He surveyed the overstory, he  surveyed the understory in each  of these stands and, bless his  heart, he compiled all this  data.  He was a very careful scientist.  It was all sitting in files in a  room in my building in Birge  Hall for me to discover with  delight and reuse when I could  revisit, sometimes 50 years to  the day after they were  originally sampled, and using  his original maps and drawings  and species information, revisit  the same locale and ask how had  this community changed from what  it had been 50 years ago.  What we discovered is that there  are big changes in the woods.  In the overstory, hemlock and  cedar have become less abundant. 

 We knew that already.  Sugar maple is becoming more  abundant.  We're seeing an explosion, big  increases on the order of  hundreds of percent, for several  grasses and sedges and a couple  of ferns.  So the understory is becoming  grassy and sedgy and has some  ferns in areas.  It's also got many more of the  weedy invasive plants from other  parts, generally Eurasia.  Exotics like hawkweed and these  others listed here.  So these are the winners over  the last 50 years.  But they come at the expense of  many losers.  The losers outnumber the  winners.  We're seeing big declines in  lilies, orchids and essentially  the pretty wildflowers that used  to populate the woods. 

 Twisted stalk is down more than  75% across northern Wisconsin in  the last 50 years.  Same thing for some of these  other lilies.  This is Carl's favorite plant,  twin flower, seriously down over  the last 50 years.  So something's happening.  And, in general, a lot of these  species that have declined are  the same ones we already know  were susceptible and palatable  to deer.  The signature points to  whitetail deer.  Animal pollinated species have  declined, but these are also  just the species that have showy  flowers and showy fruit that  make themselves conspicuous to  deer.  We know the ones that are  sensitive to deer or attractive  to deer decline.  We know that grasses and sedges,  because they have their growing  points down low right at the  ground surface, they can  tolerate repeated grazing and  continue to grow.  That's why the grasslands are  grasslands in response to those  in the Serengeti or our own  Great Plains. 

 We also know that unhunted sites  across northern Wisconsin have  lost, on average, a third of  their plant species over the  last 50 years.  Whereas hunted sites have lost  about 10%.  The Indian reservations have not  lost any diversity at all, on  average, over the last 50 years.  Bruny Island State Park has lost  half or more of its plant  species over the last 50 years.  Plant diversity is crashing and  burning at exactly some of those  places where we thought we had  set aside nature in order to  protect it.  Bruny Island is also allowing  deer hunting now after not  allowing it for many years in  the '60s and '70s.  So that's the smoking gun.  These state parks that  originally prohibited hunting  having lost so many of their  plant species.  No net declines on deer-free  islands or in the Indian  reservations.  Again, all these data tend to  back each other up. 

 We're not getting any data  that's an exception or is  standing out here.  Everything is consistent with  the view that whitetail deer  acting as a keystone herbivore  to fundamentally restructure the  forests of northern Wisconsin.  Again, pros, lots of statistical  power.  We have species abundances.  Not just missing demographic  stages.  It works across a broad range of  deer densities.  It takes a bit of taxonomy.  You've got to be able to  identify sedges, that's not  easy.  You've got to be able to  interpret the date carefully.  You need a computer and some  statistical sophistication. 

 And most importantly of all you  need baseline knowledge.  And that worries me because  we're not collecting the kind of  basic data that we need in the  woods.  We have no statewide monitoring  program.  No one is going into the woods  to regularly record numbers of  hemlock seedlings or saplings or  the abundance or diversity of  understory plants.  We published this paper a few  years ago just pointing out how  much of a keystone herbivore  whitetail deer are.  The fact that they influence  acorns and oak abundance by  browsing seedlings and acorns.  The fact that they favor grasses  and sedges.  The fact that these, in turn,  can inhibit the growth and  regeneration of some of the tree  species.  They've been referred to as  recalcitrant understories  because these grasses and ferns  can prevent regeneration.  So let's finish up, let's wrap  up here. 

 Let's look at the whole system  that we have.  Deer are at the center of what  I've painted for you here.  We have some of the mildest  winters on record through the  1990s and the 2000s.  This has contributed to over  winter deer survival.  We have massive land use change  of the kind I laid out at the  early part of my talk.  Landscape structure that's  fragmented with lots of edge  habitat.  Predators that have become far  less abundant.  Feeding of deer.  All of these are causing deer  densities to be higher and to be  sustained at higher densities,  and now I've also shown you  these impacts on tree  regeneration, forest diversity.  And probably, we're working on  this link right now, the link  between invasion of exotics and  the abundance of deer, they  spread the plants as well as  creating openings for them to  grow. 

 Eventually, of course, if tree  regeneration is inhibited long  enough, the forest canopy begins  to suffer.  It shifts in composition, and if  deer eliminate all tree  regeneration, the forest breaks  up into a savanna and starts to  disappear.  And I'm not making this up or  making dire protections of the  kind that are purely  speculative.  This is exactly what is already  happened in the parts of the  Allegheny Plateau of  Pennsylvania where they've had  more than 40 deer per square  mile ever since the 1960s.  They're getting what they refer  to as fern parks, where the  understory is just ferns and the  overstory begins to break up and  they get more open conditions as  the old trees die and there are  none to replace them.  So I lay this out to you now as  a dystopia, as where Wisconsin  forests could be headed if we  maintain chronically high deer  densities and cannot figure out  some way of changing our deer  management philosophy and  approach to match deer  populations more suitably with  the ecological caring capacity  of their habitat.  Some people when they hear about  overabundant deer tend to take  Band-Aid approaches.  Let's put repellents around a  particular tree seedling or a  deer tube or an electric fence  around a plot.  Those tend to be expensive, they  tend to be local, they tend to  be temporary.  What we've got is a bigger issue  here. 

 Something that will require a  more comprehensive approach.  It's not a local or temporary  problem.  It's pervasive across our  landscapes.  It's existed now for decades.  We need to do something about  it.  It's not a minor problem,  affecting one or a couple of  species; it's completely  restructuring a whole plant  communities.  The impacts are not simple.  It's taken me and my students a  lot of time and effort to try to  piece this picture together and  I'm giving it to you in a short  period of time.  But what we're concerned about  is that these impacts of deer  could persist for decades and  possibly for centuries.  At the same time that we're  becoming aware of all these  impacts that deer are having,  the DNR is having this spat with  hunters, and hunters are  faulting the DNR for not  delivering on that high density  that they've become used to and  that they expect the DNR now to  produce year in and year out. 

 And the DNR in turn is trying to  lean on hunters to their part,  to think of themselves as part  of an ecological system and to  realize that they play an  ecological role, that of the a  predator, that's necessary in  the absence of other predators.  Deer populations have been 50%  over goal for many years in many  deer management units.  When the DNR tried to implement  the Earn-a-Buck program, they've  been slapped back, not just by  hunters but by politicians who  are listening to hunters.  There was a hearing in 2009  where hunters marched in to a  legislative hearing protesting  the implementation of  Earn-a-Buck even though the DNR  had given advanced warning that  they would only use Earn-a-Buck  as a tool of last resort in deer  management units that were  chronically over goal for  multiple years were the hunting  was not sufficing short of  Earn-a-Buck to bring it down.  Again, the DNR board decided in  response to political pleasure  to eliminate Earn-a-Buck this  past year.  So now they're starting at  ground zero, they're starting  all over again to try and figure  out what can we do.  What kind of arrangement can we  patch together with hunters, the  DNR is saying, to make this  work.  The hunters, of course, are  arguing that deer numbers are  down, and they are down  especially in parts of northern  Wisconsin probably in response  to possibly severe winter,  heavier snowfall.  Possibly also, I'll suggest to  you, because of deteriorating  habitat conditions.  Chronic high abundance has  reduced the amount of forage for  deer in many parts of northern  Wisconsin. 

 So we should be monitoring bone  marrow in deer as well as deer  numbers, I would argue.  So that brings up the whole  issue of what do we monitor.  The DNR spends a lot of time and  money monitoring deer numbers  via something they call the SAK  model, sex, age, kill.  It's based on the deer that  hunters turn in.  Hunters don't believe the data.  The data themselves tend to be  imprecise.  They have to be aggregated over  a large geographic area.  On the other hand, we have very  few resources, if any, as I've  said, to be devoted to what  impacts the deer are having in  the woods.  All the research I've described  to you was not funded by the  state of Wisconsin.  It was funded by federal  research agencies, primarily the  National Science Foundation. 

 So even though the DNR has been  very cooperative in doing some  of this work.  So I argue that in fact we're  missing the boat here.  We're perhaps needing to spend a  little less money up here and  arguing over deer numbers and a  little bit more money down here  to really understand what's  going on in the woods.  Let's use a little bit of  science in our management.  It's interesting to me that this  is again exactly what's happened  already in Pennsylvania in  response to this document a  review of monitoring deer  affects on forest ecosystems in  Pennsylvania.  They concluded that it was  inefficient and expensive to  monitor deer numbers, and it  made more sense to monitor the  deer impacts directly in the  woods and to base management  decisions on those impacts and  not to worry about whether  it was 14.2 or 17.5 deer  per square mile.  Likewise, we've started here in  Wisconsin to try and pull  together a deer impacts  monitoring consortium.  We could monitor the deer in  more detail taking advantage of  hunter data.  As well as monitoring seedlings  and plants in the woods to learn  more about what their impacts  are.  So to summarize, game management  was historically based on the  need to protect and enhance herd  sizes. 

 Deer went extinct in southern  Wisconsin.  They became rare in northern  Wisconsin.  We needed those hunting  regulations that we had, with a  short season favoring buck  hunting, in the early 20th  century.  But all those things that made  perfect sense then make a lot  less sense now in a landscape  where deer have become  hyper-abundant.  Forest and deer management are  working now synergistically to  create overabundant deer herds  in many parts of the state and  throughout the eastern US.  Deer acting as a keystone  herbivore with serious  ecological impacts.  Conventional hunts, just when we  need them the most, are  appearing less successful in  controlling deer numbers in the  Chronic Wasting Disease zone and  in chronically overpopulated  deer management units.  And increasingly, we have deer  management becoming a political  football of controversy.  Just at a time, again, when we  need a more cooperative  approach, a more scientific  approach to management.  So if you're interested in  reading more about ecological  change in the state of  Wisconsin, pick up a copy  of "The Vanishing Present."  The 34 chapters were written at  a level to make them accessible  and understandable to as many  people as possible. 

 There are some disturbing  chapters but there are hopeful  chapters too.  We have wonderful success  stories.  The sandhill cranes and now the  whooping cranes coming back into  the state.  We've got recovery of water  quality in many areas.  So a lot be to proud of.  Wisconsin has been at the  vanguard of wildlife and habitat  and natural area management.  I think we need to maintain that  forefront position.  How can we decrease deer  densities?  Well, it's fairly obvious.  Favor doe hunting.  Emphasize the key ecological  role of hunting. 

 I would like to see hunter  education actually involve  ecology for some segment.  I think everyone who is  considering becoming a hunter in  the state of Wisconsin should  learn something about the  ecological system that they're  becoming a part of and the  ecological role that they're  playing as a hunter.  I'd also like to see, well these  are all techniques that the DNR  has been using, special seasons  and zones, doe permits.  You need a booklet now to keep  track of all of this, it's  gotten pretty complicated.  Meat donation programs help  hunters who are able and  interested to take more than one  animal.  It's possible too that wolves  will continue to increase in  abundance to some extent.  It may be that in parts of  northern Wisconsin they are  helping, if not to bring down  the number of deer, at least to  change their behavior so that  they're impacts on plants are  reduced.  Deer tend to move around more  when they're in areas where  wolves are hunting.  It's also possible, I think we  should consider this, whether we  could run habitat in reverse for  some place larger than that  Sylvania Tract, that 15,000  acres.  Something more like 50,000 or  80,000 acres, where you can get  a patch of old growth that was  large enough actually to bring  down deer densities over time. 

 But my basic message is just the  need to integrate our general  approach to managing forest with  our approach to managing  whitetail deer.  So thank you, very much, and  thank you to the funding  organizations that have made  this possible and my current and  former students that have worked  so hard on these projects.  It's been a real pleasure.  [APPLAUSE]