Return to video

>>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? ^M00:03:28 [ silence ] ^M00:03:34

>>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. ^M00:10:35 [ silence ] ^M00:10:49

>>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 ,the 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. ^M00:45:01 [ silence ] ^M00:45:09

>>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.

Return to video