Fragmentation, Roads & Wildlife Corridors (Fall 2011, part 1)

Fragmentation, Roads & Wildlife Corridors (Fall 2011, part 1)


>>Let’s go on. So our next lab — you know, we’re going to do the midterm
here, but our next series of labs, when we get back
to our labs next week, are going to start to address
this issue of fragmentation. We already started that with
the lab that was due today, that I moved to being
due on Wednesday, which is our Google earth lab, to start to look
at fragmentation. And again, for that lab
I just said we’re looking at apparent fragmentation. So I don’t expect that you know
that color patches dark green and one’s light green, I don’t
expect that you went down and analyzed what species
of trees those are. This is just gross
visual landscape elements. This was our first lab activity
to start to look at this; to look at the large
scale of what’s going on. One of the most — this is a
badger out on about three miles from campus here, out
on the Oxnard plain. So badgers are not exactly
— they’re not endangered, but they’re not common. We’ve had them reported
for decades in this area but you don’t frequently
see them. In this particular case,
this guy’s out in the middle of the agricultural fields. He was probably — so
this is a little bridge with a little drainage ditch
underneath this section of road.>>[inaudible question]>>I think it’s right
after the stop. I think it’s on that side
of the stop, I think. And so don’t know exactly,
but it seems very likely that he was going up
and down this waterways as a disbursal corridor. It was kind of cruising down
and then for whatever reason, decided he wanted to go over
the road and was bad news for this guy and he got whacked. So roads are a real
challenge for mobile animals. Again, as we’ve been saying
the last couple lectures, these themes are popping
up over and over again. These landscape-ecology themes. The scale of which something
is happening, energy’s flowing, animals are moving
,what have you. Spatial variations —
special heterogeneity and how that community is
stuck together. Disturbance in the inverse
which is stability and now that we’ve had our
discussion on metapopulations, this part starts to make sense. Number four, which
is patch-orientation. We have a bunch of patches. Are they in a daisy chain? Are they shot gun splattered
across the landscape, etc.? And this idea of species area
curves as we sample larger and larger areas we tend to
get more and more things, more and more categories
of our subject of interest. So currently, Caltrans
in California, whatever the [inaudible] you
want to pick, our county roads, our county public works,
etc. Folks that think about transportation
and planning cities and urban corridors and things of that nature are currently
really big on wildlife corridors and why might that be? Why are wildlife corridors
a hot topic these days? Any thoughts? [ silence ]>>No. I didn’t sleep last night. You guys slept. You should have some
kind of answer.>>Cassidy: [inaudible comment].>>Okay. Okay, so the
public safety thing and stuff like that. But why now? Why are people suddenly in
the last few years, decade, or so really into this stuff? All the things Cassidy
said were right. Gene flow and all these
kind of good things, but –>>[inaudible question]>>Yeah. I’m just telling you that they’re increasingly
popular. Things to think about;
have a conference about, have a planning session about. I’m asking why.>>[inaudible question]>>Right. Right. Because we’ve come — we’ve finally come around to
realizing what a massive imprint we are exhibiting
on the landscape. This is a great paper. This came out a few years ago. This is a very simple — a
great example of a study. A very simple thing. This is something you could
have done in a senior thesis when you guys are capstones,
something of that nature. All they did was go and get
publically available GIS data for roads in the 48 states,
in the continental — the contiguous United States. And they just grabbed all those
roads and threw all those roads on the GIS — threw them
on a map and said, okay. It’s the area of the U.S.
and for those of you that are in GIS, they created a bounding
function; an area around each of those lines, each
of those roadways. Said, how much of this land is
within x distance of a road? And this is the summary. So on this x axis
this is distance from the nearest road in meters. On this axis, this is the
proportion of all of the land in the lower 48 states that
falls that distance or closer. So for example, if
we were curious, we want to know 50% we
could come here, drop down, and we find that about half of
the land in the United States of America is within about
500 meters of a road.>>[inaudible question]>>What’s that?>>[inaudible question]>>Yes. Well, so this
isn’t even all the roads. These are just major roads. This does include some
trails and some forest roads, but it’s by no means every
little teeny tiny trail. This is just sort of
the relatively easy to get data that’s out there. So it includes some dirt roads,
but by no means all of them. So this is freakazoid. Check this out. So this says that within
about two kilometers, about 90% of the land, the
area in the lower 48 states is within about two-ish
kilometers of a road. That’s insane. That’s crazy. This entire continent. That is amazing. We don’t perceive
that typically. We’re in the car driving to
the store and school and stuff and maybe it doesn’t
seem like that big a deal because we don’t drive
this massive network. The only way you really
get a feel is if you — like I was just on an airplane. Coming in, you look out. Or, if you have a
tool like Google Earth where you can actually spend a
half hour, just screw around, zoom in zoom out, and you
can actually start to begin to appreciate how ubiquitous
this road network is. Here’s another way of
saying that same thing. In this case looking
at water sheds. Same idea. Here’s the lower 48 states
and this is the proportion of water shed area that is
essentially close to a road or has roads in the water shed. And so we go from pull, meaning
that to the water shed has roads in it, to the hot colors meaning
a lot of almost the entirety of the watershed
has roads in it. Yeah?>>[inaudible question]>>Yeah. Great question. So the question, is what,
for example, this guy — what were the roads and are they
cement, asphalt, dirt, gravel. And this is — they
just grab stuff. This is primarily paved roads but it does include some
unimproved roads, some gravel and dirt trails, fire roads
an stuff, but includes most of all the main roads. But it doesn’t include all
the little teeny tiny arteries and stuff. So it definitely is
biased towards paved roads. Yes. So that means if we do add in all the different
possible roads, this would go even higher. This is the bottom-most part. And we do not pull up roads. We only build more roads. So if we did this
a decade later now, if anything it’s going
to be even higher. So what’s the pattern
you see here? Again, blue not that much of
the water shed contains road; hot means a lot of the
watershed contains a road. What’s the pattern we see?>>[inaudible comment]>>Okay. What about
spatially speaking? Where are the most
fragmented roads — where are the most
fragmented watersheds?>>[inaudible comment]>>East Coast, right. This whole Eastern
Seaboard zone. Anywhere else?>>[inaudible comment]>>Us. Us. We’re incredibly hot. Same as Seattle, kind of
Pacific Northwest, kind of deal. And where’s the least
fragmented zone — zones?>>[inaudible comments]>>Right. The inner
mountain zones. So between the Sierras
and the Rockies, right. The desert area. We have the lowest population. We definitely have roads, but
because they’re fewer people, it’s not like San Francisco
or San Diego or something where you just these mesh
networks overlying everything. It’s more like one big
road going from this valley to the next kind of thing. So roads are ubiquitous
but there is some amount of spatial segregation
to these — to where the fragmentation
is occurring. [ silence ]>>Just have a large
picture here, sorry.>>[inaudible question]>>I’m not sure. I’ll go back; but this thing
will take forever to load back. So this is not a North
American phenomenon only. We see this all around
the world. So here’s an example of major
arterial roads in Europe. Europe totally innerv — Europe probably the most
innervated large region on the planet with roads. The Romans started doing this and they were experts
at building roads. And many of the roads in
Italy and Spain and many parts of Europe — the
roads are still — the roads used are still
things built by the Romans. So one of my old technicians
up at Stanford — we talked — it was some conversation one day and we talked about
the old road. And I said, oh yeah,
let’s take the old road. He goes, you do not have
— he’s from Portuguese — you do not have an old road. I’m like, what do you mean? Like, we have an old
road in my village. I’m like, really. So like what’s the old? Our old road was
built by the Romans. This was built by the, you
know, whatever he said. They’re Spanish, whatever,
they’re not old or something. So these road networks are real and they have real
consequences to critters. So roads have a couple
different types of impacts. First and foremost, they’re
effecting the immediate local zone around the road itself. And one of the most
obvious things — the thing we’re going
to start looking at after our midterm is
absolute direct killed critters. That’s going to be
called direct mortality. It can be called road kill. And it’s very easy for
us to see road kill if we have our eyes peeled. Roads also are the starting
point for the erosion in many cases of ecological
community integrity. So we can have that erosion of
these ecological communities if we fragment an area, or even if the road isn’t
actually fragmented – if it’s on the left side
of the site or whatever, it can degrade; lead
to a degrading of an ecological
function of an area. And then in some cases if
the road is big enough – let’s say we had
a small frog pond, the road could just absolutely
straight up obliterate it. So we can cut it in half, we
can be near it and mess it up or we can just completely
remove it. Another major local scale impact
of roads would be pollution – facilitating pollution. Now pollution can happen in
a couple of different ways. The most obvious is air and
soil pollution via deposition – via particles coming
from our vehicles, either because we’re
braking with our foot and we have our brake
pads which squeeze onto this fast-spinning object
and that causes friction and we have little particulars
of copper and things come off. And that material falls on
the ground, kind of thing. That can be from the stuff
coming out of the tailpipe. The atmospheric material that
goes up and then deposits in the shrubs and stuff,
say alongside the road. So we can have air and
ground pollution, basically. We can also have
water pollution. And that comes from
when this deposition — so the oils from our leaking
pipes and such, or whatever, go on to the road
bed and they sort of stay there may be initially
they’re just on the road but when we have
the next rain event, it pulls that material off. And, in fact, in some
places like deserts, even if there’s no pollution
at all, if there’s no oils or anything else, the very fact that we have a hard road
will change how water flows in the desert. So the shrubs will be different
sized right next to the road versus 20 feet away because
essentially you’re collecting all the water that hit the
road and shutting it right to the side so you’re actually
watering the plants along the side of the road. So you can change the ecological
interactions that way. And then something that we
don’t typically think of but is hugely important is
this notion of noise pollution. And we’re so used to hearing
obnoxious blowhards like me talk when my voice isn’t hoarse. And music and video
games and TVs and stuff; it’s really instructive. As one of the activities
you’ll do when we do our road
kill lab is you’re going to do some vehicle counts
and just stop by the side of the road a couple of
times just for a few minutes and count the number of cars. And when you do that just chill
out with your iPod playing. Just sort of side of
the road, safe place and everything and just listen. I mean these roads
can be incredibly, incredibly loud things. And for us it might be annoying;
for an animal trying to breed or reproduce or call a mate,
whatever it is, that can drown out their ability to
do that communication. And there’s all kinds
of ultra-hydrology and nutrient cycling and
all that kinds of stuff. So local scale impacts
from road fragmentation. Next, we can talk
about regional scale. So we’re getting a
little bit farther away from the immediate direct
vicinity of the road. So in this sense, roads frequently
facilitate invasive species. Roads are the route
– the free pass, the freeway in to bring things
we don’t necessarily want into more intact systems. There’s a huge interplay
between urban sprawl and roads. So the notion’s, oh my god,
we can’t drive and traffic is so horrible, let’s
build some more roads so that we can drive
more quickly and then because we can drive
more quickly, it’s like, hey let’s put another
city out here. Because now, it’s only 15
minutes to get to that city. And this sort of feedback
loop thing goes on.>>[inaudible question]>>I’ll show you another
picture in a second. Roads facilitate invasive
species because right here. So this is a place up in
the San Francisco Peninsula that I used to drive every day. And the cars we’re driving — and I have a better picture in
a second, but since you asked, very heavily trafficked road. Lots of vehicles, you
know tens of thousands of vehicles a day, if not more. And eventually somebody’s
going to break down. You know, laws of
probability and nails in the road, whatever it is. Flat tire, bad engine,
something. You cruise to the side —
you cruise to the side — if this is all dried — late
summer dried grass and things of that nature, and you pull
off the side of the road with a super-hot wheel,
because you had a flat tire, or your tailpipe is super-hot,
and you touch that grass, there’s an excellent
chance you’re going to start a fire, right. So what our roads maintenance
folks do is they go, oh my god, let’s go and clear
all this stuff. So we go and we whack
down all the vegetation and so there’s nothing in
the way that might ignite. Or if there is a fire,
it’s very low vegetation and it will just smolder. In doing that, we’re knocking
down long live things. We’re knocking down trees,
we’re knocking down shrubs, we’re knocking down perennial
long live plants, in many cases. The things that come in
are disturbance-loving; disturbance-filling things. And many times those
are weedy things. And many times weedy things
are non-native things. Does that make sense? We also sometimes come in and herbicide the
heck out of the place. And we can get into
whole discussion about Roundup resistance
that is now spreading — now spreading amongst
across our roadways thanks to Monsanto that’s like to
create crops that are resistance to Roundup so that
you on your crop — or you on your lawn can
go and spray Roundup and kill everything
except for what you want. The problem is that resistance to Roundup gene is
now getting out. And so that’s a whole
other conversation. Okay, so facilitates
evasive species primarily by being the disturbance
vector and humans continuing to disturb the roadsides. Major interplay with
urban sprawl. It’s oftentimes the initial step
in regional resource extraction. If you’re going to go in a do
a mine, if you’re going to go and log that forest, almost always the first
step is put in a road. And those things often
very deleterious effects on ecosystems. And then lastly in
this slide, at least, roads and trail impacts
never are contained. Road and trail impacts
are ever expanding. At least roads and trails in natural landscapes
meaning we drive. Or whatever — a hiking trail. Pick a hiking trail
up in Santa Monica. Hiking [sound effect] all
good and everybody’s walking, single file and nobody’s
going out. Right, that never happens. But assume that happens. All of sudden, you know, three
weeks from now, it rains. Oh my god it’s all muddy. Are you going to walk
through the puddle and get your shoes three
inches deep in water? No. You’re going to step
to the side and walk around which is only natural. But then what happens
is that trail – the start was this
wide; goes to this wide. Because you’re walking in there
you’re creating little divets. Now it’s going to be muddy. So the next guys that
come through in a month or so are oh my god I
don’t want to get my — so roads are every expanding. Intentionally, unintentionally, just the effects are
constantly spilling over — spilling over and widening. So here’s an example to show
what Steven was asking about. This picture — what’s
this picture? This picture’s up on
the way to Vincent Beach up in Northern California,
north of San Francisco. And this is a nice shot. This is springtime. You see all of our mostly
invasive grasses from Europe and Asia and the
hillsides growing. But what you see here
right along the side of this small road
— two lane road — is all this yellow stuff. Very pretty — looks
very pretty. This is actually a non-native
species this is Brasican Nigra. This is a pernicious weed and
it is growing where the road is. On the other side of the fence,
where there’s cattle to eat it, it’s definitely there, but it’s
nowhere near this abundance. So in this case, we have all
the disturbance that comes through in Caltrans or park
service or whatever it is, comes and herbicides this,
sprays this pesticide to kill all the plants so
that there’s less plants to potentially start fires
if someone goes off the road. And so all the native guys
that might occupy that space and the longer live
guys that might occupy that space are disturbed and
knocked down and knocked down. So who comes is the
disturbance-loving or the disturbance critters. And in this case, if
the cows had access to the full road it would keep
them down too but they don’t. So in some cases, like
Robert was saying, also in some cases
along the roadside, we intentionally plant
weedy non-native. And so this is a term that
we’ll talk about later but NIS, which stands for
non-native invasive species. This has to do with the
terminology, which we’ll talk about later but you can
just write non-native invasive species. So sometimes we intentionally
stick in these things like ice plant ; like
this beach dune grass from Europe and other things. Because we put this road in
maybe this soil was denuded and we wanted something
to hold the soil. And people are like, I want
something that grows instantly, like tomorrow, let’s
plant this stuff. And so we’ve directly
facilitated the introduction of some of these things. And then, independent of those
things, this is just easier for things to move
up and down here. So it’s easy disbursal corridor. And I already said selecting
for disturbance-filling species and roads are a factor. In North America, something like
about 50% of endangered species, roads factor into why
they are becoming rare. They are killed with road kill
or their predators are coming in through the road or
something of that nature. And we already talked
about this. There’s this positive
feedback loop with urban sprawl where we start with congestion
and then it goes, oh my god, we need more roads to
alleviate the congestion. Let’s build more roads. And because we can build
more roads you can drive more quickly. That tends to foster
more cities and then because those cities
get occupied all of a sudden there’s more
cars and it’s congested, and it’s this positive
feedback loop. So this slide just
represents that, don’t worry about copying
all this stuff down. This is just sprawl
facilitated with roads. I mentioned also that roads
are often the first step in resource extraction. This picture is in the Amazon. And you can see there
was an intact forest, at least on the left. And on the right it’s starting
to be cut down and burnt and all that horrible stuff. And the mechanism for that is
this dirt pipeline of a road. Most of the time these roads
go into a straight line or pretty straight
line to the mine or the dam, or whatever it is. Or a pinch point if we’re
talking hydrological stuff. Increasingly, roads in the developing world
especially are put in to serve multiple functions. So first and foremost is often
for economic development. So very poor folks — we
want to start mining an area so we can get some money so we can build some
schools that kind of stuff. But they’re also a factor
in a whole variety of things like projecting military power. The reason we have
our highway system is because people wanted
to kill the Russians. So in the Cold War, we
made these new things — these intercontinental
ballistic missiles. And people wanted to be able
to move those missiles on semis and stuff all around the
U.S. and/or move troops around as the Reds came in
and invaded the country. So the initial impetus for funding the interstate
highway system was national security. There was all these extra
benefits helping the economy and stuff, but the real
initial thing was to be able to project military power
around the U.S. better. People often talk about
poverty alleviation; that’s what they’re doing
in Turkey right now. So there we go. So let’s talk now
specifically about road kill. So all those things are going
on but let’s just pick road kill because that’s an easy one
to wrap our heads around and see some of the examples. Any questions about
this stuff so far? Make sense to everybody?>>[inaudible question]>>Sure. Sure, yeah. Right. I mean so it is — a fire
can be a bad thing, absolutely. I’m not saying that
you shouldn’t clear — that you shouldn’t chop down the
weeds on the side of the road. But this is an example of this
road factor ever expanding. You never just put in a road. You put in a road and then
have to do the maintenance. And then because there’s
something come off the hill you have to do something
with the culvert. And the effect is
always expanding, expanding, expanding, expanding. Road kill — this is
tough to really measure. Because we, and we will
do this in our class – we will measure road kill rates. It’s hard to figure out
some of the other rates. The death rate of
rabbits due to hawks. The death rate of rabbits
due to coyotes and things. But road kill at least we
can see and the suspicion is for at least several different
species that the source of mortality that is cars is
greater than almost all, if not, other aspects in the life
of these mobile animals. So the most likely way
they will die is via a car. This is especially true for
large, slow-moving things that are the kind of things
we are most likely to note or see an article in
the Ventura County Star or something like that. So bear, deer, mountain
lion, coyote, but even the smaller
things like rabbits — like this rabbit here on the top
of the trail grade and snakes. So there’s a couple
crazy things about this. One, the bear’s going out. Two the people appear to be
swerving towards the bear. So, you know, I’ll
just say that. So there you go. Good times. Animals, when they want to move
and we fragmented their habitat in many cases they
will find a way around. So here’s a case where
we have put in a road where we put some
type of barrier to try to exclude the animal from
crossing — in this case a fox. A fox doesn’t care. He’s going to go and
look around the whole way until he finds the little
gap that maybe to you and I doesn’t appear to
be that big, but get under and then he might be screwed. Here’s another one where
the fence actually did — was contiguous with the
ground but some animals – that wasn’t enough for
them so they actually dig – they excavated their
own way to get across. They were so interested in
going from one side of the road to the other which suggests that
something – mates, food, water, you know, whatever
the case may be — they needed to go across there. If they had all of their
requirements on the side over here, they wouldn’t
be spending all this time scratching and digging through
rocks to try to go under and through a death
maze, basically. So this is a wolf in
Croatia that was killed. We’ll talk about
these in a second. We note when this happens, we
note when it’s something big that — Now, a rabbit
is sad and is bad, but you probably don’t care
too much about a rabbit. And most people probably don’t
care too much about a rabbit. This thing, if you hit this
thing, doesn’t matter if you like warm fuzzies or not,
if you hit this thing, there’s an excellent chance
that your car is screwed up and you might get
into an accident. You might actually die. Right. So this notion
of wildlife-human, wildlife-vehicle encounters is
not a totally esoteric thing even for folks that don’t
perhaps value natural populations as much. It’s a true risk to themselves
as well to the critters. This is not only an issue with
roads, this is also an issue with any kind of linear
transportation system and the most obvious
one is railways. And so this is a bear. This is in Croatia as well. Or — yeah, I think
this one’s in Croatia. So we’re going to do, next
week after our midterm, but we’re going to essentially
take a look at our county. Our county is pretty
cool for many reasons. One, cause we’re here. Everybody say “yeah.”>>Yeah.>>There you go, see? You guys are good. But we’re really
interesting and for a study on road kill we’re
particularly well-suited. We have coast, we have inland. We have about a third of
our county is wilderness. About a third of
our county is ag. About a third of our
county is urban suburban. We have wet lands,
we have rivers, we have coastal mountains,
inland mountains so we have — it’s kind of a neat place. Very few — we have snow — we can be in the snow and then
half an hour later be outside surfing, right. So we have this really
interesting cross-section of different communities and
things and so it’s a nice place. So the question is — so
one of things we’re going to be spending time looking
at is trying to figure out what’s — how many animals
die in our part of the world? And as a focal region —
we have two focal regions – one is the Santa Monica
National Recreational Area. And so it would be interesting
to know how many animals die, plus or minus some
error, each year? Is it 50 animals? Is it 500? Is it 5,000? Is it 50,000? What’s the deal? Secondly, we’re going
to be interested in asking what’s the kill
rate of animals on roads across the entirety
of the county? Same thing. What’s the average
number of things whacked, plus or minus some error? If we take again only
the major roads — this is not all the roads, this is not a little
teeny forest trails. This is just the major roads,
county roads, state roads and throw them up on a map. So here’s the pink — here’s
the Santa Monica Mountains we’re going to look at but for
this figure I just put up Ventura County. And the roads are
a little line here. The yellow is the area within
one hundred meters of a road. The darker burnt
orange color is the area within 500 meters of a road. And what pattern do you see?>>[inaudible comment]>>Right. So the only place
where’s there’s some decent, not massively, completely,
totally fragmented area is up in our wilderness and
that part of the county. You know, Oxnard, Thousand
Oaks, wherever you want to pick. Everywhere else, it’s almost
the entirety of the landscape is within 500 meters of a road. So if you’re a critter,
if you’re a rabbit, if you’re a snake, if
you’re whatever the heck, that’s a real threat to you. That’s why road kill is either
the greatest source of mortality or one of the very high ones. And again, it’s something
we don’t appreciate. This is one measure of how
fragmented our ecosystems are. And this is what started me
thinking about this and working on this and doing
the lab for you guys which was a female coyote
I saw a couple years ago up on Potrero Road here. And for various reasons I was
leaving sort of late in the day for a couple of weeks
and I saw her like four or five times cross the road
from going up Potrero here up the right, cross over onto
the land just to the left of the road and she
was a pregnant female. And then one day I
drove and she was dead on the side of the road. And her pups were
obviously dead, too. And it was very sad. And it got me thinking, like,
how often does this happen? And when I asked
folks, nobody knew. And so that’s why we
started in with this project. As we’ve already
heard, the roads act as a constricting factor
to disbursal and movement, etc. So as we now know, unfortunately this slide
is a couple years old, but it serves to make the point. As we now know, our last
tagged mountain lion was killed approximately 7 weeks ago
by someone maliciously, intentionally, that just wanted
to kill it, and took the collar and all that kind of stuff. And it was killed over here. And as you know, right about
that same time, a juvenile one of its offspring was
killed over here on the 405. That was road kill. And what you see here, these
are the radial track — this is a collar; animal’s
moving around and this is over the course of a long
period of time their range. So this is where the animal
routinely going to walking around looking for
food, mates whatever. And what we see is basically
for this guy, this male, this dark sort of oval shape – essentially the territory
is the entirety of the Santa Monica Mountains. So as know these
guys are asocial and they don’t really do well
with overlapping territories. So this says that the entirety of the Santa Monica Mountains
is habitat for maybe one or maybe a few mountain lions. And what’s bounding it, the
Oxnard plain here with all of our roads, PCH, and the
Pacific Ocean – so right there. Santa Monica and all those roads and this thing right
here is the 101. So the 101 is a real
barrier to movement. And the long-term, if we
don’t do something about that, there will not be mountain lions in the Santa Monica Mountains
except for some actors, you know, Hollywood
retreat studio or something like that, right. So a real challenge. A real challenge to
figure out what to do this. Okay so here’s our
first example. Let’s look more in
depth at road kill. In this case, we’re going
to jump over to Florida and we’re going to talk
about the Florida black bear. The Florida black bear
lives in a forested area. It prefers closed
understored vegetation so you know the dark
forest thing – not so much an open
meadowed type critter. These bears are omnivorous
so they’ll eat dead animals. They’ll eat plant
materials, whatever. The bulk of this bear’s
diet are mostly nuts and roots and berries. They particularly
like palmetto hearts, which is these little sort
of palm-shaped looking things that are small but we don’t
really have them around here, but they are common
on the southeast. The male – the adult
male is something on the order of 220 kilos. Females, roughly
about half that size. And it’s Florida’s largest
remaining terrestrial mammal. They have manatees and things but on land the largest
remaining mammal. They’re asocial just like those
mountain lions we talked about. The males have territories
on the order of about 175 square
kilometers and again, similar to the mountain lions , he females have a
smaller habitat. In this case the females have a
quite significant smaller home territory I should say. Moms give birth to
somewhere between one to three cubs around
the new year. And Mom takes care of that
cub or cubs for about a year and a half, at which point
she goes in estrus again and kicks the juveniles
out and she mates again. A black bear in Florida,
we think historically, had something on the order of
a one to two decade life span. That’s a pretty long
lived critter. They were declared
federally threatened. We haven’t gone in depth
into endangers species yet, but real quickly, suffice it to say we have not
worried candidate for listing threatening
endangered and extinct. So these guys first went
on this warning of level that we call threatened in 1974. We think that historically,
meaning on the order of five hundred odd years
or so ago, in the state of Florida we had something
like 12,000 bears, you know, kind of pretty disturbance
basically. And the last estimate that I
know of from 2007 estimated that we had somewhere
between 1,000 to 1,500 bears. So but a fraction – about 10%
of their historic abundance. This is some data for
bears killed by cars. You can see this on the right . If it’s a little low and
you can’t quite see it, this is time back in
the date until now. They’re listed as
threatened in 1974 so right around then they
started monitoring this. So the first day that we
have is 76 and this data goes up to 2004, but the
pattern remains. And over this 28-year period, about 1,350-ish bears
were killed. So over this 30 year period,
and again the lifespan is about 20 yearsish, we as many as we think are alive right
now died by cars alone. So cars are a major source of
mortality for this critter. Also note that the kill
rate by cars is going up. It’s not staying stable
it’s not going down. And that’s because more
people are moving to Florida. More roads. More vehicle trips. All that. More shopping malls
,all that kind of stuff. And so this is typical
— – oh, shoot. I took my son and dad to go see
the last space shuttle launch this summer and i went here and actually have
better, new pictures. And I just realized I
forgot to put them in. I apologize, but you
guys get the idea here. This is a closed
forest on either side. There’s no barrier. There’s no wall. There’s no fence. And so you can see how it’s
relatively easy for the bear to [sound effect] walk through
their desirous place and all of the sudden in the
middle of a killing zone. And for this poor guy,
that’s what happened. So here’s the distribution — the remnant black
bears in Florida. Pink is their remnant,
primary best habitat best place where they can hang out
the blue represents areas where they can hang out but
it’s not idea and so they’re in various spots but this area
right here in the northern part of the state has more than
half of the road kill depths. So this even though
they are everywhere, there’s this huge hot spot here. So if we’re talking about road
kill as we are today this is where you got to start or this
is where you want to start to figure out what’s going on. So these are kills over about
a two-year period in the early to mid 90s and this is the
Atlantic Ocean on the far right, right here this is Daytona Beach
where you know spring break and you so know big
urban center, big you know hoity toity Daytona
500 and all that kind of jazz. And then as we look off to the
left, as we’re looking more into the interior part of
the terrestrial environment, the light gray color here
represents forested area that’s potential bear habitat. The lines obviously
represents roads. The colorization is a little
– I got this from a PDF and it wasn’t the highest
quality PDF, so I apologize, especially if you’re
in the back. It might be a little
hard to see, but the red triangles
represent a bear kill. So a bear was whacked in this
approximately two-year period. The pink dots represent what’s
called the bear nuisance report, meaning someone saw a bear
on the side on the road and maybe it was wounded. Maybe they just saw it
and they called the cops or animal control or whatever
but they never found a body. So therefore, stare at this and you guys tell me what
the pattern is to bear kills in this part of Florida. So just take a minute and just
stare at this for a second. [ silence ]>>So they’re around
roads, okay, okay. But what else?>>[inaudible comment]>>Okay. Okay.>>[inaudible comment]>>Okay so Alex is
saying that the area — if we look over to the
left part of the map here, where we have more of the
lightish gray color that appears to be more kills
in that area, okay. Maybe. What else?>>[inaudible comment]>>Say again.>>[inaudible comment]>>Okay, so roughly
the number of lanes — the size of the road is related to the thickness
of the line here. So we have the observation that where there’s thick line
roads there’s more kills, is that right? So it’s definitely associated
with the roads, absolutely. But it is always with
the thicker lines?>>[inaudible comment]>>Okay, so these
are like two lane — like that picture I showed you. These are one or two
lane back country roads. These thicker ones are more like
the 101, you know, like four or five lanes each
way kind thing. So which kind of
roads have more kill?>>[inaudible comment]>>Why?>>[inaudible comment]>>They’re in the bear habitat
but here’s a bear habitat. Here’s a bear habitat as well.>>[inaudible comment].>>Right. Good. Robert?>>[inaudible comment]>>Right. So you guys
are saying — Robert and Cassidy are saying
basically the same thing.>>[inaudible comment] Right. Exactly. So you guys are
all basically hitting on the same thing.>>[inaudible comment]>>Yeah, this appears to be
a fairly realistic barrier to bear disbursal, right? There’s one, two, three,
four maybe that are not. You know that are to the
east of that major artery. So that’s true. That’s good. And so the thing that you
guys are picking up on is if you have the 101
what’s the 101? Right? The 101 is even
if you’re on it at 2 in the morning, zing,
with the low. So one time, when I was
just a new graduate student, the Northridge earthquake
happened. There was a whole crazy story
– I could tell you the story if you want me to tell the
story, but basically I thought that I left this totally nasty
evil gas on my desk and it was in an office and it wasn’t — it was like an office
– it wasn’t labeled. And I heard that they’re going
door to door at UCLA checking to see if there’s
wounded people. And I was freaked out. There was going to be like
this 50 year-old secretary lady like going, hello, is
anybody there, open the door and die from this gas. So I jumped in my car because
I couldn’t get through to UCLA because the lines
were screwed up. And I drove to campus to make
sure that no one was going to open that door and die. And long story short, I was
living in Manhattan Beach and so I got on the freeway
and drove from Manhattan Beach, which is south of
LAX, all the way to Westwood and passed two cars. So it was like the
end of the world. It was like Omega Man. It was like very,
very disturbing. You like never see that again. That was pretty much
one of the only times when that road segment
in the last who knows decades didn’t have
gazillion million cars going on it so even at 2 in the morning its
zoom, zoom, zoom, zoom. And then most times of
the day [sound effect]. So you’re right. A bear or a whatever is going to
walk up and kind of go uh, what? It’s essentially a wall
of moving metal, right. You had to be chased by
a predator to even think about bolting in
there in most cases. So in effect, these thick
roads have relatively speaking, relatively speaking, fewer
kills because they’re so intimidating sound
wise, visually, however you want to slice it. It’s these smaller roads
where it is more like zoom and then nothing for a while and
the bears like [sound effect]. You know, like looking
right, looking left and then like hey I’ll guess I’ll
go across here and then like some you know [sound
effect] some Don Johnson and his Lamborghini comes by, or whatever the heck,
and whacks you. So over this one section of
road again the same period. These are the kinds of things that during the intensive
survey they found in terms of road kill. Organisms that they encountered. Yeah?>>[inaudible question]>>Correct. Correct. And we will have
a lot of question marks. Cause things get smushed.>>[inaudible question]>>Oh no. Don’t know what
species of snake it is. They can tell it’s a snake
but it is too smushed to tell. So that’s unknown
snake, unknown bird, and that’s unknown
unknown, kind of thing. So yeah turkey vulture, a
gray fox, a water moccasin, which is a kind of snake, a
hawk, a cardinal, snake, owls, alligator, you know different
birds, turkeys, the cooter is like a duck kind of things. Egrets, snakes, deer,
bear, turtles, tortoises, armadillos, rabbits, possums. All this stuff, right, from
this one section of surveying. So you can imagine if
you extrapolate this out how many critters are
killed and the diversity of the things that are killed. In our surveys we’ve been
doing our surveys now for about five years
— five and half years. I think we had 78 categories of
things that we’ve seen killed. So there’s potentially a lot
of stuff dead on these roads. So this is how this can
be helpful for planning. This isn’t an activity, right. Conservation biology is not
an activity where we go up and say you dummy
stop doing that right? It’s really about
providing tools to help people minimize
the impact. And this is how we can turn
that data into something useful. So for example, on this
particular case this study was done because these folks wanted to expand this particular
roadway – state route 46. And so by doing this
road kill survey by quantitatively measuring
the mortality on this stretch of road they were
able to determine in measuring the traffic
volume on this section road, different times of the year
and stuff, they were able to correlate the
number of dead bears, for example, with the flow rate. And so we have on
the bottom here — this is a daily traffic volume. So this range is from 2,000 cars
per day to 16,000 cars per day. And then on this axis, this
is the number of bears killed. And so it’s a very
simple regression. You can do it much more
elegantly but for quick and dirty they do a
simple regression and show that as the traffic
volume increases, more bears are going
to get whacked. So what you can do is you can
take the slope of that line and you can use it as a
first gross approximator. And what that line tells us
they’re starting with X roads of X size and we want to
say add two more lanes. Say we want to double
the capacity or whatever the case may be. This simple relationship tells
us in this case, from this data from 76 to 99 that if we
expand the road we’ll get one additional bear death per year for every additional 2,5000
more cars per day on the road. So that’s cool. Now we can have an adult
conversation about this. Now we can say is
it really important to make this road larger? Maybe it is. But we were going into it
wide-eyed, saying if we do that — if we made 5,000
more vehicle trips per year, we’d expect on average
two additional bears to get whacked each year. And so we say, okay,
well, that’s not good. So yes, we’ll let
you do that expansion if you help us make
paths for the bears or make a bear rearing
facility whatever it is. So we can use this data, which
is not complex, but is very key. And without this data
we’re shooting in the wind. It’s like, I don’t know if
we make it big, is that good? Is that bad? So here’s an example of how
road kill data can truly help us with planning and stuff. The first thing you can do,
the simplest thing you can do with road kill is
to put up signs. Say hey there’s a
lot of animals here. Don’t drive too fast. But people tend to
not read the signs. This is a sign from Australia
and it says watch out road. There’s like kangaroos
and emus and camels. And this emu here did
not read the sign. So signs are the
first thing to do. No problem. Relatively cheap. Relatively easy. You can definitely try it. May it will work. But usually we have to
go beyond simple signage and the invention here which
was really first thought about and really started to use
in Europe is this notion of wildlife crossings. And wildlife crossing is a tool,
is a structure that is intended to connect one contiguous
habitat. It could be forest, it could be
meadow, it could be wetlands, whatever, that are fragmented by
something – a linear structure. A trail, a road, a
railroad, whatever it is. And so in this sense they’re
one type of wildlife corridor. And a corridor is a place where things can move
through the matrix. Associating wildlife
crossings with roads as I said is a European idea. Now people are using it
all around the world. Wildlife crossings include
a variety of structures. Some take animals over the road. Some take animals
under the road. So wildlife crossing is one
sub type of wildlife corridor. This is a fake picture. This is not real. But this is sort of
an idealized version. This is photoshopped up. But here we can see — here’s our road and this
would be maybe sort of more of an ideal type situation
where we need to put a road in for whatever reason; a
railroad, a autobahn, something. And it would be cool if we had
areas that were essentially old, intact healthy landscapes. And it would be great if
there were multiple places where the critters could
go across as opposed to a single pinch point. A single pinch point is
better than no pinch point. But the ideal setting would
be lots of places for critters to safely move across
this dangerous structure than the cars could get to
do what they want to do. The animals can get to
do what they want to do. In the case of the
Florida example – going back to Florida now, we can use existing
structure sometime. In this case in Florida this is
a wet place and so people know that and so they don’t want
their road to be flooded so we have some of
these underpasses that were originally
put in for water to flow under in the wet season. So you put a camera out there. Our site putting
out camera traps in our wetland restoration
there. And these things can be
activated in different ways. They can be activated
in pressure plate which is essentially a
fancy trigger for the camera when an animal of a
certain weight steps on it [sound effect]
it takes a picture. Or they can be infrared
triggered. And so in this case we see an
alligator going underneath the road so he’s not
getting wacked if he were to cross over the road bed. Here’s a different view of that
place in a different season. And we can see what they’ve done
here is the road is elevated, water can go underneath. And by the way, animals can too. And so here’s one thing
that’s very common you’ll see. One, we have this actual
crossing structure. Two, we have something that
helps guide the organisms to that crossing structure. In this case, this is a fence. So this is expensive and
we might only have one of these crossing
structures every so often. And it would have to be pretty
lucky for animal to just kind of [sound effect] and
magically hit this spot. So what you do, is you put a
fence out that way and a fence out that way and now if the
animal hits me I’m golden. Hits my shoulder, he’ll get
directed towards my chest. Hits my hand he’ll
go towards my fore– you know, it’s that
kind of stuff. So it’s a way of
directing animals to the safe place to cross. Okay. We’re almost to
the breaking point here. So I haven’t updated
this in a while, but it’s because we don’t
really have great data so people don’t really
study this. So it hasn’t really
changed that much. But these estimates aren’t meant
to be perfect but they’re meant to rather give you a sense of
the magnitude of road kill. In 2004, we had 253,000
automobile accidents where the car struck an animal. And just FYI, if you ever did — do hit a deer, or something
like that, do not clean your — do not wash your car off. The tendency is people like wham
and it dents their headlight up or whatever the heck. And they come home
and rinse it all off. Wait. Call the insurance
guy to have him come over. Because they want to see
there’s fur on your thing. Otherwise they’re like oh
this idiot ran into a post or something like that right. So anyway that’s a side note. One estimate that’s not really
necessarily backed up by data but it’s more like what
a lot of people say but at least it’s out there. Something on the order of about
a million vertebrates killed in the lower 48 states
on roads every day. That’s huge. Every day. Right? Now, that’s
not all bears. That’s you know snakes
and rabbits an stuff but still it’s a huge, amount. In Yellowstone, in 2004 alone,
6 bears were killed by cars. As of 2004, this thing over here on the right this is
the West Coast version of road kill bingo
they sold 25,000 games. So what this is this
is bingo just like B42. In this case, it’s for when
you’re driving with the family at Yosemite or whatever
the heck and you’re trying to keep the kids
occupied in the back, you can do state license plates,
or you can say, who saw a tire? Who saw a dead squirrel? Who saw a dead deer? Right. And it’s kind
of a novelty thing like a quirky [sound
effect] Christmas gift. But if it was just
a silly game — if it was just sort
a silly joke gift, you’d probably sell
several thousand, or something like that. You wouldn’t be selling 25,000. So this must be at
least vaguely telling us that some people can
use this as a game right which is some indicator of the
level of dead things around. In the state of New
Mexico in 2001, we had 2,349 large vertebrates,
meaning big deer, wolves, like that large kind of animals. In Sward National park which is in Texas they have estimated
they have 51,000 vertebrates killed each year, and these are
mostly the larger bodied guys and then closer to
home, here in the Mohave where we have our
desert tortoise, which isn’t somebody doing
desert tortoise this semester? No. Okay, good. So desert tortoise
used to be abundant. Now, it’s heading
toward extinction and they move very slowly. If you pick them up, they
like oh my god, they urinate. They really die because they
blast out all their water and they usually
die of dehydration. So they don’t move quickly. So in this one section where
we had a lot of dead tortoises and their population numbers
were going down, we put a fence around one 15 mile section
of this highway and just that fence alone reduced the
road kill by 93% which said that most of what was
taking this local part of this population out
at least was this road. I think we will put
it on pause there. So we’ll pick this
up on Wednesday.

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