wildlife

How Roads Impact Wildlife – The Environmental Impact

rocarroll Wildlife , , , , , , , , , , , , , 0 Comment
How Roads Impact Wildlife – The Environmental Impact

Roads have become increasingly common across our globe as people utilize them to travel to places they want to go, increasing the reliability on cars for transportation needs. These large and wide networks of roads we know today severely alter a landscape and can impact wildlife in numerous ways. As seen in my previous blog posts, roads can cause impacts to wildlife such as mortality, wildlife-vehicle collisions, and limit their movement from place to place; however, roads can also shift the population demographic of a wildlife species and become a source of pollution into the environment. Roads impacts extend well beyond the surface of the road itself, causing many ecological impacts to the environment and the wildlife within it.

Habitat Fragmentation & Alteration

Roads can cause direct mortality to wildlife, causing other factors to occur such as wildlife shifting their population demographic farther away from the road, losing vital habitat space. Roads also pose a number of indirect effects onto wildlife, such as habitat fragmentation and alteration. This is due to either wildlife not being able to cross a road due to the risks of mortality or through avoiding the road altogether, shifting their habitat farther away.

Roads also create barriers that limit the movement of wildlife, one of the main issues being barriers prohibit gene flow. An example of this was seen when a group of researchers studied the genetics in timber snakes; snakes that were blocked in their movement from roads had a much lower genetic diversity than other snakes across continuous habitat types. Along with this, the male timber snakes are known to follow pheromone trails to find mates; roads disturb this trail and make it difficult for the males to be able to find mates, affecting reproduction and survival of the species.

Wildlife being affected from habitat fragmentation and alteration are also susceptible to not being able to access specific habitats. An example of this is during dry seasons; when there is a drought occurring, road prohibit wildlife from reaching vital water sources. Roads can also prevent some wildlife from reaching nesting sites, such as turtles; these species end up laying their eggs in habitats where there is more predation, meaning their is a decreased chance of reproductive success and survival of the species.

Constructing a road also alters the habitat altogether. If a road is running through a forest, the road creates an edge habitat along the parts of the road that fringe the forest itself. This can have severe consequences for wildlife, especially birds; when an edge habitat is created, birds become more susceptible to predation. This is due to predators being able to prey on birds much easier in the edge habitat, as the forest canopy at the edge offers less protection to the birds and their nests. Other wildlife susceptible to edge habitats are turtles; some species of turtle prefer to nest along edge habitats because it is an ideal habitat for their nest. However, turtles utilizing the edge habitat are now posed to a greater risk of mortality when crossing roads, and their hatchlings could also be susceptible to this when they disperse after hatching from the nest.

Pollution

While roads can alter habitats and cause fragmentation to occur, they can also channel pollutants onto the environment. Debris from tires on the road can cause things such as a decreased amount of time to metamorphosis for the wood frog species. Salt that is used to deice roads runs off the road and into adjacent ponds that can decrease the survivorship of species such as spotted salamanders and wood frogs. Deicing salts can also change frogs behavior and decrease their performance in locomotion. Frogs are one the species that have been shown to have greater skeletal abnormalities when they are closer to roads; researchers suggest this is a result from the road contamination. This is turn affects the frogs fitness, making them potentially less adept to catch prey or elude themselves away from predators.

Roads polluting the environment extend far beyond introducing chemicals into the environment; they also introduce noise and light, which can be detrimental to wildlife as well. The noise from traffic on a road can effect species of bird, causing declines in bird populations living in proximity habitats close to the road. However, not all species of bird are equally affected, such as how birds having song frequencies similar to that of a car frequency being found as absent from habitats near roadsides. Noise from a road can also change bird species’ community composition, meaning that some species of birds are differentially excluded from a particular habitat near a road.

Along with noise polluting the environment, light can as well. Some species of wildlife rely on light to control biological activities, and this can be impacted by lights along a road. For example, robins use sunlight as a cue to begin their morning songs and can mistake lights on a road for the sun and begin their song in the middle of the night. Lights from roads can also alter flying routes for bats, as well as expose some frog species to artificial light during the night that could delay their metamorphosis time. Along with this, sea turtle hatchlings use light in order to navigate themselves to the sea and can become confused by lights on a road and go toward a road instead of the ocean; this can cause the hatchlings to die from dehydration, predators, and /or wildlife-vehicle collisions, and they will never reach the ocean. This goes for the females that nest their hatchlings as well, sometimes becoming disoriented from road lights and have a difficult time getting back to the ocean.

A final note on pollution from roads is that is can facilitate the spread of invasive species when land is cleared for a road. An example of this was seen in Australia with cane toads; these species of toad are very invasive in the continent and use roadside areas to move, causing an increase in their range as a population. Along with this, species such as fire ants may also build their mounding nests by areas cleared for roads because this is an ideal habitat for them. Roads can facilitate the invasion of invasive species, and alter or fragment a habitat; all of this impacts are detrimental to both wildlife and the land they live in.

Mitigation Strategies

There are numerous solutions and mitigation strategies being developed to help decrease the amount of harmful impacts our roads cause to wildlife. In instances where the pattern of mortality can be predicted for a specific are during a specific time of year, roads are either closed or reduced in their speed limits to decrease the rates of wildlife mortality. Another solution is creating artificial nesting sites for gravid species that need them; this can reduce species from needing to potentially cross a road, the distance they need to travel, and/or their chances of mortality.

A main issue with roads is the traffic volume on them. Though decreasing traffic volume is not very likely to be effective for a mitigation strategy, constructing alternative methods to cross a road could become more successful. For example, culverts can be used for smaller animals to allow for a safe passage under a roadway; this has been shown to be highly effective in decreasing mortality rates of wildlife. For bigger animals, overpasses can be used to cross a road; this overpass would need to have specific features of the wildlife’s environment, such as vegetation planted over it to mimic the habitat type.

There are many factors that need to be taken into consideration when ensuring wildlife can effectively and efficiently cross our road structures. We need to implement and create new ways to protect and preserve our wildlife, as well as the environment they live in. From this post, we have learned that roads not only impact wildlife through things such as mortality or vehicle collisions, but roads also create very real and severe threats to the environment that in turn affect wildlife. We as humans have a job of conserving our planet, and that includes the wildlife within it. Without the wildlife, there would not be an environment for us to destruct upon, as wildlife naturally disperse seeds, nutrients, and vital resources the environment needs to keep going.

“We are part of the environment, just as much as wild animals are. They do not seek to kill us, we seek to kill them. It’s surely our responsibility to do everything within our power to create a planet that provides a home not just for us, but for all life on Earth.” – David Attenborough.

How Roads Impact Wildlife – Raccoons in Our Neighborhoods

rocarroll Wildlife , , , , , , , 0 Comment
How Roads Impact Wildlife – Raccoons in Our Neighborhoods

It’s the end to a wonderful day. You just finished cleaning up from a delicious dinner and start getting ready to take the trash from the day outside. As you walk outside to your trash barrel, you notice a pair of eyes peering out from inside the barrel. Pausing, you slowly grab your phone to turn the flashlight on, only to be met with a bandit: a raccoon! Raccoons are known as trash pandas or bandits, sneaking into people’s yards and going through their trash, only to disappear into the night. What people are not aware of is that we are attracting raccoons right into our suburban and urbanized areas. How you might ask? Read on to find out why!

Image of a raccoon standing on a tree stump.

Why Raccoons are in our Humanized Landscapes

Raccoons are very smart and intelligent creatures, seeming to be increasing in their abundance within urbanized landscapes; the question to ask is why? Why are these creatures becoming established in our urban landscapes rather than hiding in the forest where they are from? The answer to this question is one that has been discussed among wildlife biologists for years, and the reason seems to be that humans are unintentionally participating in the education of raccoons. Over the past 80 or so years, raccoons have made this astonishing surge in their populations, having their highest densities within suburban areas and slowly increasing in cities. Raccoons have well-adjusted to living with and among human beings, and this has what’s resulted in raccoons increasing domination of our humanized landscapes.

How This Issue was Established

Researching this issue lead me to Suzanne MacDonald, a biologist and psychologist from York University located in Toronto, Canada. She has been researching this issue and her work suggests that raccoons living in cities may actually be smarter than rural raccoons due to them forced to navigate man-made obstacles, such as roads. Using GPS collars to track raccoons, MacDonald found that these raccoons started to avoid major roads that crossed, almost suggesting raccoons have learned how to avoid cars. From this, it seems humans have inadvertently created a mini classroom within our cities for raccoons to learn from and become “perfect urban warriors” within human landscapes. But the question still remains, how do these creatures navigate their way into our human landscapes?

Crossing the Divide

Raccoons typically live in forested habitats that are heavily wooded with access to many trees, water, and vegetation. They make dens out of hollowed out trees or abandoned burrows made from other animals. When they search for food, they can travel up to 18 miles per day while foraging. However, over the past several decades, we’ve seen these creatures make there ways into our humanized landscapes and become successful at living quite efficiently within cities and the suburbs. The question still remains, how did raccoons make there way into these landscapes, away from their natural habitats? The answer to this question is roads; have you ever been driving down a road and noticed two glowing eyes peering out from a storm drain? More than likely, this pair of eyes belongs to a raccoon, as they use storm drains as a safety underground tunnel before crossing a road from one side to the other. Storm drains, also called culverts, were originally created for channel streams to pass under roadways. Now our wildlife creatures have found a safe and useful way to cross roads, without interacting with the traffic or cars up above. If these culverts or storm drain systems were set up on each and every road ever made, then animals would have a safe and efficient way of crossing our man-made obstacles without the repercussions of things such as mortality or vehicle collisions.

Family of raccoons in a storm drain on a roadway.

An example of this was seen on a highway in Maryland, where a researcher noticed raccoons using the storm drains for coverage and wanted to investigate why. Low and behold, other species such as reptiles and small mammals also use these storm drains to cross under roads as well, with a study being conducted showing 57 species of wildlife using all 265 culverts in Maryland. From this, road ecology researchers can now understand how drainage structures can be formed to allow for channel streams to pass under roads as well as wildlife; this will in turn help to decrease the amount of roadkill we see on out highways and roads, especially with raccoons.

Raccoons are intelligent creatures, finding ways to to stay safe and efficiently move from place to place through our drainage systems implemented in our roads. More roads need to have the features that drainage systems pose for our wildlife if we want to keep the amount of mortalities and wildlife-vehicle collisions at a decreasing rate. Wildlife are beginning to learn the ways of our man-made obstacles, and if we research how they are doing so, we can effectively ensure that the proper features of roads are in place so our wildlife are safe.

Demotivate Yourself – Second MEME

Demotivate Yourself – Second MEME

This meme idea was sparked from my blog topic about how roads impact wildlife. I was thinking of an idea for a meme and started looking up in Google Images, “wildlife and roads”. This is when I found this picture of a brown bear sitting in the road with a car pulled over to the side; my initial thought when I saw this was, “Huh. It looks like this bear is protesting the road by just plopping itself right in the road.” This is what began to spark my caption for the meme: wildlife don’t have a say when it comes to roads being placed into their environments; they’re expected to “deal with it” or “become accustomed” to it as our society continues to build upon the environment. Animals can’t fight back against humans or the infrastructures built on their land, meaning they become susceptible to mortality or harm when coming face to face with a car driving down a roadway. I chose the caption, “Protesting roads because killing wildlife with your car isn’t enough anymore” because this seems to be what the case is these days; wildlife are now constantly susceptible to mortality, vehicle collisions, or other factors from roads (i.e., destruction to habitat, pollution, erosion, etc.), and the only way that people would seem to start becoming aware of this issue is if the wildlife started protesting (if they could). However, the point of this meme is to become aware of the fact that wildlife may not be able talk about how they are affected by roads, but how they are being affected is what matters and what needs to cease.

ds106assignment

How Roads Impact Wildlife – Considering Already Existing Roads vs. New Roads

rocarroll Wildlife , , , , , , , 0 Comment
How Roads Impact Wildlife – Considering Already Existing Roads vs. New Roads

Roadways act as barriers to the movement of wildlife populations as they attempt to move from habitat to habitat, sometimes making them susceptible to things such as mortality, wildlife-vehicle collisions, fragmenting and/or destructing habitat, interrupting ecological processes, and increasing pollution and erosion. To find solutions to the issues roadways pose, one thing researchers in road ecology have found is debating whether to keep the number of road’s already existing and expand off of those, or to keep increasing the number of roads that already exist by implementing new ones. From your perspective, what would you do?

In the Real-World

Researchers studying road ecology and attempting to understand the impacts roads have on the adjacent environment or wildlife populations have used various methods to understand how mortality impacts wildlife populations through road systems, such as through increasing the number of roadways or traffic volume that already exists. Studies conducted on this found increasing traffic volume on existing roads have a lower impact on wildlife than creating new roads (Rhodes et al, 2014). When measuring levels of traffic volume, researchers assess impacts to wildlife; this can be done by accounting for risks towards wildlife populations along with various species that could be affected. Researchers investigating this were able to determine that traffic volume creates very substantial and negative consequences for wildlife, even as traffic increases (Charry & Jones, 2009).

What This Means for Wildlife & the Environment

When researchers in road ecology are developing plans to either extend an already existing road or implement a new road into the environment, there are a lot of considerations to be factored: how the road will be implemented to cause the least destruction possible, how the road once implemented will impact the surrounding environment (i.e., roads fragment the edges of an environment, causing an edge effect to occur), how the road will cause wildlife to potentially use it for crossing, etc. These factors are important, and from the studies described above attempting to understand this more, it is seen that extending already existing roads is much more beneficial to wildlife and the environment than creating new roads. Traffic volume is another consideration that goes into the plans of road ecology; the amount of traffic on a road can create very substantial and negative consequences for wildlife, such as increased wildlife mortality or wildlife-vehicle collisions on the road. However, when considering the pros and cons between the two options – either implementing a new road or extending an already existing one – the latter seems to have less consequences for the land and the wildlife surrounding the road. Road ecology should be broadened to consider how extending already existing roads rather than creating new roads would benefit wildlife and the environment as a whole, such as less instances of mortality and vehicle collisions while also increasing ecological processing in the environment overall. Road ecology could also broaden itself by implementing solutions into new road plans to create a new road that is wildlife and environmentally friendly, such as the ecopassages discussed in the previous post; this in turn would help the issues of traffic volume by giving wildlife an alternative to cross the road. Wildlife and the environment deserve to be tread upon lightly with care and compassion, as we have little left of what we started with. Roads are helpful for humanity to get us where we need to go, but in the end, is it worth sacrificing the land we have left for new roads, or leave the land for the wildlife to use and for the purposes of producing more of the natural environment and resources needed in the world today?

How Roads Impact Wildlife – Ecopassages as a Solution

rocarroll Wildlife , , , 0 Comment
How Roads Impact Wildlife – Ecopassages as a Solution

As I’ve driven along highways, interstates, or roads, I can’t help but notice the amount of roadkill I see at times; a raccoon here, a turtle there, but wait, there’s also a turkey vulture up ahead. It’s disheartening to see the amount of wildlife that have been susceptible to colliding with a vehicle on a road. Roadways act as a barrier to the locomotion of animals moving around in their environments; they have been shown to increase wildlife mortality and decrease the quality of their habitat. Roads have ecological impacts as well, including, but not limited to, fragmenting and destructing a habitat, interrupting ecological processes, and increasing pollution and erosion.

Looking at the Big Picture

To reduce the impacts roads have on wildlife populations, ecopassages have become integrated into the planning of roadway systems, or road ecology. Road ecology provides an integrated and solution-oriented framework for addressing the environmental effects of roads. The goal of road ecology is to provide planners with practical advice on how to avoid, minimize, or mitigate negative environmental impacts of transportation. From this, ecopassages have become well-known and improved upon by implementing effective steps into road ecology research. Ecopassages are overpass or underpass systems that are used to enhance wildlife movement over or under roads and have shown to lessen the impacts of road ecology; they reduce situations of wildlife morality, wildlife-vehicle collisions, and limited wildlife movement. Ecopassages are thought of as a solution to the impacts wildlife populations face from roads, and have been found to be effective and efficient in aiding wildlife to cross roads safely.

In the Real-World

An example of an effective and efficient ecopassage already implemented is the Payne’s Prairie Ecopassage located on US Highway 441 in Payne’s Prairie Reserve, Alachua County, FL. This ecopassage has a series of eight culverts – a tunnel under the road carrying an open drain or stream – that underlie the highway system with entrances and/or exits on either side (Figure 1). The researchers who studied this ecopassage found that it was effective and efficient through finding reduced number of roadkill on the road after the ecopassage was implemented. This ecopassage is just one example of how there are solutions to minimize the risk we pose to wildlife with implementing roadway systems into areas of land.

Figure 1: US Highway 441’s barrier wall-culvert system with eight underlying culverts spanning across the highway.

Wildlife have a place on this Earth, the same as humanity does. However, the biggest issue we face with coexisting with wildlife is that we pose threats to them from implementing things such as major transportation infrastructures. When humanity makes these big-scale plans, it’s important to remember the impact the infrastructure may pose to both the environment and to the wildlife populations within that environment. Roads are a useful infrastructure to humanity, as we use them to travel to all kinds of different places. Despite this, humanity also needs to take into consideration what’s around the roads as well: the created fragmentation of the habitat left surrounding the road, the wildlife attempting to live near these roads, and the possibility of the wildlife attempting to cross roads to travel from habitat to habitat. With these factors kept in mind and the continuing of implementing ecopassages into road ecology plans, hopefully the future will provide less impacts to wildlife populations so them along with humanity can coexist in more peace.

css.php