Monthly Archives: March 2015

The Effects of Urbanization May Be More Hopeful Than You Think

Urbanization is defined as a continuously expanding urban area or core municipality [1]. Urbanization is becoming increasingly prevalent as the human population grows. This is the main cause for habitat loss and fragmentation, two driving forces in the current extinction rate, which is 1000 times that of the historical rates [2]. Species capable of living in the urban environment tend to exhibit specific characteristics. These characteristics include high thresholds for fear (cortisone levels), short flight distance, high reproductive rates, capability of maintaining high densities (of the same species), and species adapted to high disturbance and/or edges [3]. Animals without these characteristics (and plants without the last three) are unlikely to thrive in urban development [3]. Over time this may cause a homogeneous landscape where plant and animal species are increasingly more alike and species that cannot survive in these areas to go extinct [3,4].

In a recent study conducted in Southern Australia, Isaac and colleagues used habitat selection to examine the behavioral responses of 6 arboreal marsupial species in Australia to increasing levels of urbanization [4]. There were three similar sized areas used in the study, a highly developed area with mostly impervious surfaces, an urban fringe area with a mix of impervious and other land cover, and a completely tree covered area [4]. Throughout the experiment, each marsupial species selected different habitats based on their development level splitting into three groups across the landscape: a disturbance-intolerant group (3 species), a moderate tolerance group (1 species), and a disturbance tolerant group (2 species) [4]. Therefore the potential for habitat to be suitable for these marsupials was significantly based on the urbanization gradient [4].

This study gives hope for the future of biodiversity, as it can be applied to urban development everywhere. It will be virtually impossible to stop urbanization from occurring more frequently, however people can build a civilization that is more integrated with the native environment. By creating this urban gradient some species diversity can be sustained. However, a critical piece to this is a need for ample area in the urban fringe and forest cover environments like in the marsupial study discussed above [4]. If the urban areas continue to expand, then the urban fringe section for the moderate tolerance group and the forest cover patch for the disturbance-intolerant group can get too small to sustain populations [4].

Now is a time when human development choices can forever alter life on earth. Instead of thinking of humans as a separate entity from nature why not think of them as interconnected? Debating whether something is “natural” due to amount of human influence may be irrelevant to present and future biodiversity [5]. Humans have been altering ecosystems for centuries and some of those changes are positive. For instance, pre-Columbian indigenous people in the Amazonian rainforest would compost to create sustainable forest gardens [5]. These ancient gardens continue to show a positive ecological footprint as Amazonian Dark Earth (ADE) which is one of the only soils rich in carbon found in these forests today [5]. Given the marsupial study, it is possible that present day animals have an ability to coexist with humans based on an urban gradient. This would mean that human disturbance like urbanization is capable of maintaining biodiversity if it is conducted in a sustainable way.

– Savannah Maynard

 

Works Referenced

  1. http://www.demographia.com/db-define.pdf
  2. Carolan, Michael S. “Greenhouse Gases: Warmer Isn’t Better.” Society and the Environment: Pragmatic Solutions to Ecological Issues. Boulder: Westview, 2013. 15-39. Print
  3. http://link.springer.com/article/10.1007/s00442-008-1259-8
  4. Isaac, Bronwyn et al. “Simplification Of Arboreal Marsupial Assemblages In Response To Increasing Urbanization.” Plos ONE 9.3 (2014): 1-15. Academic Search Premier. Web. 3 Mar. 2015.
  5. http://www.freewebs.com/alexlees/new%20uploads/Barlow%20et%20al%202012%20Biol%20Cons.pdf

Illegal Hunting: What’s the Big Deal?

Illegal hunting is an increasing issue around the world, especially in Africa. Africa has many endangered species such as lions, elephants, and rhinoceros. In fact, your favorite animal or an animal you expect to see at a zoo is likely one of these endangered species. Our favorite endangered animals are being further reduced because of illegal hunting practices. So how are conservationists trying to save our favorite animals?

To combat illegal hunting, conservationists first need to know where illegal hunting is taking place. Knowing where illegal hunting is happening can help pinpoint areas to focus on that have an increased prevalence of illegal hunting and effectively reduces the amount of illegal hunting in those areas. In a recent study, published by Animal Conservation, Kiffner and colleagues were able to use animal behavior to determine if illegal hunting was happening in certain areas1. Observing the behavior of animals in certain areas can expose the prevalence of disturbances in that area. Kiffner and Colleagues eliminated other disturbances, such as approaching predators, by specifically observing how eight large herbivore species reacted to being approached by humans 1. The researchers noticed that how the herbivores responded to human disturbances was reflected in their use of the habitat and group size1.

Kiffner and colleagues chose four areas in Africa to observe the responses of these eight herbivore species to humans. The areas that were chosen were: Tarangire National Park, Lake Manyara National Park, Manyara Ranch Conservancy, and Mto Wa Mbu game-controlled area1. These areas were selected because of the differences in location, hunting policy, enforcement and human access1. In Tarangire National Park, Lake Manyara National Park, and Manyara Ranch Conservancy hunting is not allowed. However, hunting is allowed in Mto Wa Mbu with a permit but not of endangered species, of course1. Hunting is strictly prohibited in the two national parks, so rangers closely monitor them. In contrast, Mto Wa Mbu and Manyara Ranch Conservancy areas aren’t closely monitored. The reason why was not specified in the study, but I’m assuming it’s because there is a lack of money to hand out to employed rangers1.

The results of this study showed that many of the observed herbivores changed their behavior depending on the study area they were in. In Manyara Ranch Conservancy and Mto Wa Mbu, the herbivores were more aware of human presence and fled more quickly. These two areas were also less protected and had a higher predation risk. By contrast, in the two national parks, where hunting is strictly prohibited, the herbivores viewed humans as less of a threat and decreased their flight initiation distance. The researchers believe it’s because the animals had some way of knowing that the area is protected and, therefore, there is less of a predation risk1.

Only half of the herbivores that were studied responded to humans in a negative way. Therefore, Kiffner and colleagues could only conclude that observing animal behavior is merely a stepping-stone to revealing if illegal hunting is happening in certain areas1. I agree with their final conclusion that animal behavior can only be a signal for possible illegal hunting. In my opinion, it depends on how familiar the animals were with the areas that were studied. These animals could be displaying high alertness because there is a high risk of predation from other animals, not just humans. To my knowledge, the herbivores’ other predators were not accounted for in this study. This could have given the researchers false-positives of what was making the herbivores behave in the observed manner in these areas. This misinterpretation of the animals’ behavior could potentially lead to ineffective management decisions on how to reduce illegal hunting in certain areas, and in the end waste money that could have been used in other areas that are actually experiencing illegal hunting. However, if these behaviors do pinpoint areas that are experiencing illegal hunting, then conservationists can implement strategies to effectively reduce the amount of illegal hunting that is happening. Reducing illegal hunting practices is not only helping with the recovery of endangered species, but it also gives future generations the opportunity to experience these animals as well.

 

 

 

  1. Kiffner, C, Kioko, J, Kissui, B, et al. (2014). Interspecific variation in large mammal responses to human observers along a conservation gradient with variable hunting pressure. Animal conservation, 17(6), 603-612.

 

Using Behavior to Deter Elephants from Crop Raiding

Standing next to an adult elephant is incredibly intimidating; adult male African elephants can weigh more than 15,000 pounds. Many farmers fear and hate them because cropraiding elephants can destroy entire fields and even threaten farmers’ lives. Imagine an angry farmer going up against a hungry 6-ton elephant! In southern India, during a three-year period 60,939 incidents of cropraiding occurred and 91 people were killed [1]. This also presents a problem for the conservation of elephants because retaliatory killing of elephants often occur and public support of elephants is incredibly important for their survival.

There have been many methods tested to deter elephants from raiding crops, however, elephants are often too big and smart for these deterrents to work: elephants will push over fences or simply go around them [2], culling problem animals just makes way for new crop raiders, and the electrical fences set up by the government will either be destroyed by the elephants or fall into disrepair because of a lack of upkeep [3].

Some new and upcoming methods to deter crop raiders include using elephant behavior to keep them away from cultivated land. It may be humorous to think about the largest land mammal running in fear of a simple bee, but because of the thin skin around elephants’ eyes, trunk, and under their legs, they are actually susceptible to bee stings just as we are. A swarm of bees has been known to send entire herds into flight [4]. Setting up bee hives along well known paths and near key habitat areas, such as water sources near crops, has been proven to deter elephants from those areas, however, often times the elephants will go around them to get to where they want to go: the water hole, or the tasty crops [4]. Although “beehive fences” won’t completely work to deter an elephant from a whole crop, they can be used along well-established paths either to guide them away from a crop or keep them from coming near water sources near crops.

While humans rely mostly on eyesight, the elephant’s most powerful sensor is their nose. Just like a human could be blinded by a bright light, elephants are “blinded” by extremely strong scents, which is why another promising elephant deterrent is the creation of rope fences covered in chili grease. Chili grease fences are created with a mixture of chili essence, motor grease, and sometimes tobacco [2]. One farm encircled by a chili rope went un-raided for two years despite nine attempts [2]. If there is a way around the fence, the elephant will find it. However, when faced with the decision to either go near the fence and get to the crops or leave, all elephants chose to avoid the fence and the crops were protected [2]. The downside to this method is the constant upkeep of the rope: the paste must be reapplied at least once a week, more during the rainy season.

These methods of deterrence that utilize animal behavior are extremely promising because they are specialized for specific behaviors and are non-lethal to endangered animals such as the elephant. Decreasing crop raiding through effective methods that do not harm the animal is one way of improving conservation efforts for elephants. Villages with agricultural practices are much more likely to support conservation efforts when their livelihood and lives aren’t being threatened by neighboring elephants.

 

-Mackenzie Platt

Citations

  1. Gerhardt, K.V., Niekerk, A.V., Kid, M., Samways, M., and Hanks, J. (2014). The Role of Elephants Loxodonta africana Pathways as a Spatial Variable in Crop-Raiding Locations. Orynx 48(3): 436-444.
  2. Sitati, N., and Walpole, M. (2006). Assessing Farm-Based Measures for Mitigating Human-Elephant Conflict in Transmara District, Kenya. Oryx 40(3):279-286.
  3. Moss, C.J., Croze, H., and Lee, P.C. (2011). The Amboseli Elephants: a Long Term Perspective on a Long-Term Mammal. University of Chicago Press, Chicago.
  4. 4.Vollrath, F., and Douglas-Hamilton, I. (2002). African Bes to Control African Elephants. Naturwissenschaften 86(11):508-511.

Look Both Ways! – How Learning About An Animal’s Behavior Can Help Them Cross Busy Roadways

Look Both Ways! – How Learning About An Animal’s Behavior Can Help Them Cross Busy Roadways

By: Michelle Bernecker

Canada's Banff National Park overpass

Canada’s Banff National Park overpass
Image courtesy of The Wikimedia Foundation

Have you ever been driving on the highway when you think you see something out of the corner of your eye, and then suddenly there is a deer staring straight at you in the middle of the road? Well, every year in the United States, an estimated 400 million animals are killed in automobile collisions.  Over 1 million each day [1]! This statistic is reflective of mammals, birds, reptiles, and amphibians.  Wildlife vehicular collisions are not only a threat to wildlife, but also humans.  The most serious of these collisions involve large ungulates, hoofed mammals like deer, elk, and moose.  Fortunately, conservationists studying road ecology have taken action and began to research migration habits of these animals to reduce the number of wildlife-involved accidents.  These studies include capturing and marking of wildlife with GPS collars, recording migration patterns, and pinpointing the most prevalent road crossings of these animals.

In Idaho, along US Highway 20 and Idaho Highway 87 ‘169 recorded collisions resulting in the fatalities of moose, white tail deer, mule deer, and millions of dollars in collision damage to vehicles occurred in a 4 year span’[2]. In efforts to decrease the amount of collisions, studies have begun along these highways to determine the routes of migratory elk and moose. Due to the ungulates migration patterns between their winter and spring ranges they are obligated to cross Highway 20, as no other route is available for them to take.

Between these two seasons, the highest number of elk and moose road crossings took place.  By monitoring these patterns, six high traffic road crossing areas were pinpointed along the highway. Based on these observations, scientists brainstormed ways for a safe resolution of crossing the roadway. Simple solutions such as fencing and signs warning cars of wildlife crossing to more complex ideas such as overpasses and underpasses which give animals their own safe pathway either over or under the busy road have been taken into consideration.

Ideas like over and underpasses have proven to be an effective solution for elk crossings in Canada’s Banff National Park (pictured above). “Canada began installing 8-foot-high fences on both sides of the expanded highway. They then constructed 22 underpasses and two 164-foot-wide overpasses for wildlife. According to the park service, these changes resulted in a 96 percent decrease in mortality for the parks ungulates” [3]. In the first year of implementing this idea the park saw as few as 2 reported crossings by only two different species on the overpass, but after an 8 year period, over 50,000 trouble free crossings have occurred! By studying the behavior of these animals it allows us to create solutions to everyday problems. Without the knowledge gained from studying this unique migratory pattern, there would be no way to determine how to implement an effective solution!

Although wildlife crossings are not yet widely utilized, they have proven to become a viable solution to a worldwide, and somewhat common, issue. Threats due to busy roadways, other than vehicular collision, can also interfere with foraging and mating behaviors, fragment habitats, and divide populations. As more information is obtained on these successful solutions projects like this can begin to take place!

Key Words: wildlife, behavior, ungulates, solutions, roadways, migration

[1] Culture Change- http://www.culturechange.org/issue8/roadkill.htm

[2] Project Successfully Maps Out Wildlife Pathways Across the “Longest Main Street in America”- Wildlife Conservation Society.

[3] National Geographic- http://news.nationalgeographic.com/news/ 2004/05/0512_animaloverpasses_2.html

Interesting extras: 6 OF THE WORLD’S MOST INGENIOUS WILDLIFE OVERPASSES [PICS]- http://matadornetwork.com/change/6-of-the-worlds-most-ingenious-wildlife-overpasses-pics/

A Rare and Endangered species in your own backyard

Black-footed ferret Image by Kasey Burrus

Black-footed ferret
Image by Kasey Burrus

In our growing and ever changing world, extinction rates have soared greater than ever. Around the world, species are threatened with extinction due to many issues that include: poaching, agricultural work, deforestation and urbanization. Most people know about the threatened status of the flagship species like pandas, rhino, elephants and our big cats. However, there are few people that are aware of the endangered species in their own backyard. The black-footed ferret (Mustela nigripes) was once known to freely inhabit what is now known as City Park in the town of Fort Collins Colorado (2). What is a black footed ferret some may ask? These charismatic and ferocious creatures are thought to have descended from the Eupoean polecat (Mustela eversnanni) and are closely related to the domesticated ferret (Mustela putorius) one can buy at a local pet store (1). It is not unusual for most people to have never heard of a black-footed ferret before.

The black-footed ferret has been flirting with extinction since what was thought to be its last know population was found in 1981 (2). It was 36 years ago that this species was on the verge of extinction when the last known population of 9 ferrets were brought into captive breeding to try and save. However, the captive breeding program was unsuccessful and its failure was attributed to a lack of knowledge about the species. Just 2 years later on a large ranch in Meeteese Wyoming, another population of 120 ferrets was found. This discovery was a rare and incredible find since the black-footed ferret was thought to have gone extinct. Biologists were determined to keep this population from plummeting to extinction again. However, an unexpected turn of events happened when an outbreak of K-9 distemper struck the ferret population and killed over 85% of the remaining ferrets. The team of biologists had to make the difficult decision to either bring the last 18 surviving ferrets into another captive breeding program or leave them in the wild and see if they survived (2). This time biologists were careful to observe the behavior, reproduction, feeding habits and life histories of ferrets. These key features are important for the captive breeding and rehabilitation of a species because life in captivity can be so much more fragile than life in the wild.

Another crucial aspect to protecting any threatened species is figuring out what is putting the species on the brink in the first place. After careful research and observations of the ferret’s natural habitat, it became clear that this species relies solely on extensive prairie dog colonies. The prairie dogs that live in the colonies are the black-footed ferrets primary source of food. So, the success of the colonies contributes to the success of the ferret species. Another important contribution to a successful reintroduction relies on the imprinting of killing their natural food source, prairie dogs. The imprinting that happens while still in captivity has a small window of opportunity for it to be successful and must occur within the first 60 days of life. This learned behavior is crucial to their survival in the wild once they are released and have their own kin to raise and teach.

The captive breeding program started in Wyoming but now resides in Northern Colorado Just 20 miles from Fort Collins. The facilities house over 200 ferrets and, as of fall 2014, the 3rd ferret release in Colorado happened in Soapstone, just a few miles outside of the City of Fort Collins. After 35 years, the program is looking to be very successful but still has a lot of work to do. As a breeding facility, they can contribute to the growth of the population of ferrets, but they cannot save their habitat alone. Education on prairie dog habitats and conservation is an important aspect to saving the black-footed ferret and many others species that live in this unique habitat.

– Kasey Burrus

Work Cited

(1) The Animal Files. “European Polecat.” The Animal Files. 5 Jan. 2010. Web. 23 Feb. 2015. http://www.theanimalfiles.com/mammals/carnivores/polecat_european.html.

(2) Gober, Pete. “Black-footed Ferret Recovery. Are We There Yet?” Endangered Species Program. U.S. Fish and Wildlife Services, 23 Feb. 2012. Web. 23 Feb. 2015. http://www.fws.gov/endangered/news/episodes/bu-01-2012/black-footed_ferret/index.html.

 

 

Wildlife Corridors: A Solution to Ending Roadkill?

One million! That is the number of animals killed by vehicles in the United States every day. “On U.S. highways, a vehicle hits an animal at least every 26 seconds” [1]. These animals range from small creatures like turtles and frogs, to larger mammals like deer and bears. This number even includes threatened and endangered species that are already struggling. With thousands of new drivers on the road each day, this is a problem that needs to be addressed before it gets any worse.

One way to effectively reduce roadkill is to build wildlife corridors. Wildlife corridors are “like roads for animals” [2], which help them travel across human roads safely. These animal passages, sometimes called Greenways, come in many shapes and sizes, and are common in some places around the world. Banff National Park in Canada is home to more than 25 wildlife overpasses across the TransCanada Highway [3]. In the Netherlands, over 600 underpasses and overpasses exist, making the country one of the leading experts in wildlife corridor construction [6].

Building wildlife corridors to help animals get past roads and other urban areas has been proven to reduce road kill rates. In Utah, a crosswalk system was created for local deer. After the first installations were completed, 40% more deer were able to cross the road safely than before [4]. In the Mojave Desert in Arizona, a conservation group was able to reduce turtle road kill by 93% after installing fences on either side of the highway and creating tunnels for the turtles to travel through [4].

Renee-fig1

Left: Wildlife bridge in Banff National Park, Canada. Middle: The longest wildlife bridge in the Netherlands, Zanderij Crailoo, which spans 800 meters long and 50 meters wide. Right: A wildlife bridge through the Veluwe natural area in the Netherlands [8,9,10].

Wildlife corridors range from simple bridges planted with grass to vast constructions including trees, shrubs, and sometimes even water. The most common type of wildlife corridor in the United States is the culvert, a large underpass tunnel. In order to understand why wildlife corridors are a sustainable and worthy use of our resources, we must understand something about an animal’s behavior. Why do animals cross roads, and how we can attract them to wildlife corridors instead?

Many species of turtles, for example, have specified breeding grounds which are often far from their usual habitat. In order to reach the area where they will mate, many turtles have to undergo seasonal road crossings. These turtles are not picky about where they cross the road, only that they arrive at the other side, so wildlife corridors for turtles can be relatively simple in design. On the east coast of the U.S., short fences are installed along the sides of many major highways to prevent turtles and other small animals from entering the roadway. In order to allow the animals to reach the other side, either deep buckets or tunnels have been created. In places where buckets are placed, people have been hired to collect turtles and frogs that fall into the buckets and relocate them to the opposite side of the road so that they may continue their journey. Tunnels are preferable because they do not require further human effort, but they are not feasible for roads with many lanes [5].

In contrast, wolves, such as the native populations of Yellowstone, cross roads for a different reason entirely. Packs of wolves have large territories and travel far every day to look for food and other resources. This puts them in danger every day of colliding with vehicles. An effective wildlife corridor for wolves would consist of more than a short fence next to a busy road. For larger mammalian species, bridges are preferred, but since they tend to be more expensive, large culverts are often built instead. These tunnels must be wide enough to ensure the animal feels comfortable, and not trapped. Drainage and flood water should also be kept in mind, so that the tunnels do not become inaccessible in certain weather or seasons [5].

Due to these behavioral differences between species, each corridor must be designed with a target species in mind. An underpass that works for a deer may not be effective for a frog or a bird. Therefore, it is important to understand the behavior of different animal species when considering a wildlife corridor. The behavior of the target species, including the animal’s reasons for crossing the road, must be taken into account when designing a wildlife corridor. Predation must also be kept in mind; an elk will not use an underpass tunnel if predators such as bears are often seen using the same tunnel. A corridor will only be effective if the animal feels safe using it. Therefore, different types of corridors are needed along the same stretch of road. According to Monica Bond, who has done extensive research on wildlife passages, wildlife corridors are most effective when they are placed directly adjacent to a natural area, and are planted with natural soil and foliage. To encourage animals to use underpasses and overpasses, human presence around the entrances and exits should be minimized and the edges of the overpasses should be covered in as much vegetation as possible, to prevent the animals from getting stressed at the sight of cars [5].

Many of the wildlife corridors that exist in Canada and the United States are repurposed bridges and underpasses that were no longer being used by humans. It is difficult and expensive to build new corridors around existing roads. If there are no existing bridges or underpasses available, the easiest way to implement wildlife corridors is to design them along with a new road, and then build both at the same time. This means that existing roads and highways are less likely to be fitted with corridors, because it is an expensive and time-consuming process [7].

In the larger scheme of things, wildlife corridors have been proven effective in reducing road kill rates all over the world. By studying the behavior of a target species and learning why they cross roads and how we can redirect them to a safer passage, we can make wildlife corridors increasingly effective. Supporting the creation of more wildlife corridors in the U.S. will convince municipalities to invest in building more, as well as set an example for other countries. Wildlife corridors are not a be-all and end-all solution to animal deaths, but they set the groundwork for saving species so that we can study them further and continue to learn from them.

As Beth O’Donnell Young, writer and landscape designer, said; “If you build it, they will come.”

Renee-fig2

Left: A grizzly bear in Banff National Park uses an underpass. Middle: Mule Deer in Wyoming are seen traveling through an underpass to cross a busy highway. Right: African Elephants in Kenya are seen emerging from a large underpass, measuring 15 feet high [11,12,13].

 –Renee van Ineveld

Class of 2015

[1] http://www.nwf.org/what-we-do/protect-wildlife/wildlife-corridors.aspx

[2] http://www.environment.nsw.gov.au/resources/nature/landholderNotes15WildlifeCorridors.pdf

[3] http://arc-solutions.org/new-solutions/

[4] http://www.hcn.org/issues/291/15268

[5] http://www.biologicaldiversity.org/publications/papers/wild-corridors.pdf

[6] http://conservationcorridor.org/corridors-in-conservation/man-made-corridors/

[7] http://www.scientificamerican.com/article/roadkill-endangers-endangered-wildlife/

(Photos)

[8] http://www.powerhousegrowers.com/wildlife-corridors-highways-built-for-paws-hooves/#prettyPhoto

[9] http://www.atlasobscura.com/places/natuurbrug-zanderij-crailoo

[10] http://www.theworldgeography.com/2012/06/unusual-bridges-for-animals-wildlife.html

[11] http://highwaywilding.org/

[12] http://trib.com/news/state-and-regional/article_d54eedeb-f85b-5f8a-9763-5a500d54dee8.html

[13] http://www.amusingplanet.com/2011/01/africas-first-elephant-underpass.html