Human Development + Fragmentation

Overview

Although it can occur naturally, habitat fragmentation has become threat to ecosystem stability because of human development. The most common form of human caused habitat fragmentation in Vermont is road construction. Habitat fragmentation disrupts migration patterns and contiguous habitat which is vitals for virtually all species within an ecosystem. This investigation aims to expose the negative impacts that habitat fragmentation has and the biota and human communities of Vermont and offer possible suggestions restore contiguous habitats and encourage more cooperative interactions between human and natural systems.

-Neely Fortune, Jessica Mailhot
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Interview with Dr. Stephanie Hurley -- An Introduction to Habitat Fragmentation


Although I didn’t have the chance to record it, my interview with UVM assistant professor Stephanie Hurley brought to light many fascinating aspects of the little-known issue of habitat fragmentation. The more I investigate the more daunting and ubiquitous fragmentation seems. But at the same time, it is also becoming clearer how many initiatives are currently at work trying to better understand and combat its causes and effects. By the end, the messy mental conflict of optimism and pessimism was leaning more to the brighter side.
With a B.S. in Conservation and Resource Studies, Masters Degree in Landscape Architecture, and Doctorate of Design, Dr. Hurley harbors habitat fragmentation under her umbrella of interests, which includes landscape architecture, land use planning, and ecological restoration. And with a focus on how to sustain both ecological and societal stability, she seemed like a perfect place to begin my investigation.
I met Dr. Hurley in her welcoming office on the cloudy morning of October 23. When we began she first gave me a list of other resources, including a prominent author in the field Richard Forman, whose books such as Land Mosaics, Urban Ecology, and Ecology of Fragmented Landscapes all point to her adamant claim that roads are by far the #1 cause of fragmentation. This struck me, for I had created an assumed conclusion that suburban sprawl and development was the major contributor. I hadn’t even considered roads really being a barrier before, since it was hard to compare them to the physical impenetrability of walls, buildings, and fences. Wildlife can walk over a road, but not through walls. Still, the more we discussed it, the more it made perfect sense. One has to consider the scope of the road (whether a rural side-road or a 6 lane highway), deterrence caused by noise and disturbance, and the fact that hundreds of thousands of animals are killed annually if they do try to cross.
Dr. Hurley later described the establishment of wildlife under- and overpasses that has partnered fish and wildlife with transportation agencies across the US. These structures allow the safe passage of a whole range of wildlife across busy roads, creating habitat corridors. They can work for terrestrial as well as aquatic species and come in a variety of designs. This is important because certain species require certain characteristics in order to pass through; large elk need enough headroom for their antlers, smaller mammals need areas of minimal exposure. According to Anthony Clevenger, a speaker she observed at a recent convention, if a stretch of roadway hosts 3 major wildlife-related accidents annually, then it is economically more practical to install a wildlife crossing (factoring in the cost of emergency response, health recovery, and vehicle repairs/replacement). This is startling. How come we don’t have these all over the place? What are the reasons being invented to say no? How about installing these before a road reaches this count and prevent accidents from happening in the first place? There are a handful in Vermont currently, including the crossings at the Bennington Bypass across route 279 down in Bennington County, a project started in 2004. It is meant to allow species such as white-tailed deer, bobcat, and coyotes to avoid the heavy traffic while roaming naturally across the landscape. To my surprise there is even a crossing right next to my home town that protects spotted salamanders on their trek to vernal pools. As to why there are much too few of these out there, I think one of the main reasons is one that is the cause of more than one persistent issue: failure to prioritize long-term consequences. It’s easy to say no to a big project that will cost now and save later. In modern society people’s mindsets are so corrupted by a lifestyle of instant gratification that it has become the main lens for decision making; if it doesn’t pay-off now, it’s not worth it. Why prevent an accident that statistically may or may not happen, and for which someone else will pay? I cannot begin to devise a quick solution to this cultural epidemic, but I digress.
We also discussed who and what is most at risk from the effects of habitat fragmentation. It is interesting to note that ecosystems found at the meeting of forests and meadows are home to many unique species, and because of fragmentation, these ecosystems experiencing mixed effects. In some areas meadows are being developed, leaving the forest edge adjacent to buildings.  Other areas of forest are being stripped back, allowing meadow to grow in their place, an ecosystem that has been on the decline until recently. Now whether or not this is evidence for arguing fragmentation actually has a benefit is tied into another debate. Historically, up until the mid-1800’s Vermont was almost entirely forested. It wasn’t until the great deforestation of booming agriculture that the meadow ecosystem was introduced to the area. And yet, currently there are many initiatives to preserve the so called ‘native meadow ecosystem’. So the main question is if meadows are native. They have been in Vermont for nearly 200 years, allowing many species to establish themselves into the broader system (monarch butterflies, bobolinks, etc). So depending on your perspective on this debate, fragmentation could actually be helping to preserve meadow and edge habitat and therefore helping the ecological health of the region. As for people affected, Dr. Hurley assessed those recreating in those areas will notice a difference in biodiversity. Birdwatchers will spot fewer and fewer species. Substance hunters will have to travel farther to find the same haul of game. Aside from that, sense of place will also evolve. Species once abundant will no longer be a few generations from now. Those who grew up with certain bird calls, deer sightings or other wildlife interactions will see a change, one that they will only get to describe to their grandchildren. Characteristics of living in Vermont will disappear, like the fabled moose sighting.
The reaches of habitat fragmentation do not stop there however. Although heavily urban areas are not usually synonymous with ecosystem dynamics, there are in fact many isolated ecosystems that endure in the heart of such areas. Dr. Hurley explains that vacant lots can be home for many plant species, small mammals, and on some accounts predators as big as bobcats and coyotes. The common perception of these places however are of barren wastelands, begging to be developed. Residents generally do not even consider it to be a habitat and therefore undervalue what is actually living there. I can understand this, but the next point proves that attitudes toward the environment are not black and white. People living in suburban and even rural areas end up taking on a similar attitude. Because nature is “abundant” around them, there is no harm in exploiting or disrespecting it. In this way ecology is undervalued in places with ubiquitous natural areas. Also, suburban and rural areas experience more wildlife conflict, through road crossings, agriculture, etc, incubating the desire to adjust ecology to better suit humanity. Coyotes attacking your livestock? Shoot them, there are more than plenty out there. These two ideas contribute to the lack of urgency and motivation to address fragmentation as widespread issue affecting everyone, not just the hikers and tree-huggers.

The main take-away from this interview is that habitat fragmentation is an underrated and underestimated issue that affects us all, whether in a 6th floor apartment downtown or a 6 acre farm on the fringe. It is incorrect to consider humanity separate from ecology; we all live within ecosystems. And as members of those systems, we have considerably overstepped our given power. The sooner we recognize that our ubiquitous influence is harming ourselves as well as the stability of the natural system, the more likely it is that our mistakes can be corrected. It is inevitable that humanity will interact with nature, but there is no law mandating those interactions to be conflicts. Cooperation almost always leads to mutual benefit. Add in a drop of human ingenuity, and fragmentation becomes restoration.

-Jessica Mailhot
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Crossing Paths with Wildlife - A look at how culverts can save the world

After my interview with Stephanie Hurley, I thought it appropriate to investigate one of the current initiatives tackling the ubiquitous effects of habitat fragmentation: wildlife crossings, specifically underpass culverts. Along with the great expansion of their use and construction, there are many studies being conducted on how these culverts are helping certain species and how to better design them in order the best accommodate and encourage those species. You could consider the movement for crossings to be its own experiment, a self-improving living project.
A study conducted by Rodney van der Ree, Jochen Jaeger, Edgar van der Grift, and Anthony Clevenger observed the culverts built into a stretch of highway cutting its way across the Albertan countryside. They set up sooted track plates to observe wildlife behavior, both in ratio of species and frequency of usage. Then by comparing their findings to the culvert’s physical attributes and the characteristics of the roadway involved they were able to map out each species preferences. The culvert characteristics included height, length, openness, and opening size. Road characteristics included volume of traffic, noise level, and physical width. The main species that used the culverts were snowshoe hare, pine martin, coyote, red squirrel, and weasel. Going into the results, I had the preconceived idea that there would be clear trends of preferences based on animal type: predators and prey having separate but consistent partialities. But then again being an environmental sciences major and understanding the complexity of natural systems I should have known better. The results were very particular - mammals are pickier than I thought (van der Ree).
Coyotes use culverts more with clear and quiet narrow roads. Hare need quiet narrow roads and culverts with vegetation near the entrances to use them. Red squirrels require quiet but busy narrow roads in order to use the culverts. Martins need quiet roads and a culvert with a low ceiling but open view range. And finally, weasels require a quiet road with a high and open culvert (van der Ree). As it’s clear to see, it takes more than simply having a culvert big enough to fit an animal. As the saying goes, you can lead an weasel to a culvert but you can’t make it cross.

Photo courtesy of K. Foresman from wildlifeandroads.org

But his is not the end of this study’s findings. The topography leading to the entrances of the culvert also greatly influence crossing. And what may seem like 5 very distinctly finicky species are actually following certain patterns. When considering the relative density of species, more carnivores used the culverts than prey species. This is most likely do to the wandering behavior of mammalian predators; they require large expanses of land in order to properly hunt. This is solid evidence of why these crossings are so important. They are directly helping the struggling predators that are suffering from habitat fragmentation to regain their prior territories. Also, these culverts not only prevent road kill, they also provide a better alternative for prey species to cross the otherwise exposed road which allowed predators to locate them easier. Installed properly and strategically, these culverts and other crossing infrastructures can help reverse the damage being down by roads (van der Ree).
Even though this study took place in Alberta Canada, it is still applicable to Vermont; many of these species are native here as well and can benefit from these crossings. You can look on the USGS Wildlife and Roads website page to view the current crossing structures in Vermont found at the link below. You can also see what species have been known to use each site, as well as view some photos of wildlife using various crossings. The biggest and most develop project in VT currently is at Bennington Bypass, which was began in 2004. Click the second link for more information on VT’s crown jewel of wildlife crossings.
After seeing second-hand the value and effectiveness of these crossings I am inspired to hopefully one day be involved in either the creation, upkeep, or monitoring of one. Anything that can be done to reduce the devastation of habitat fragmentation is on my to-do list.




Reference
van der Ree, R., J. A. G. Jaeger, E. A. van der Grift, and A. P. Clevenger. 2011. Effects of roads and traffic on wildlife populations and landscape function: road ecology is moving towards larger scales. Ecology and Society 16(1): 48. [online] URL: http://www.ecologyandsociety.org/vol16/iss1/art48/

-Jessica Mailhot
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Further Argument for Culvert Crossings

In July of 2013, conservation planning biologist Jens Hawkins-Hilke was briefly interviewed about his work in creating and managing VT wildlife crossings. Currently the Vermont Wildlife and Fisheries Department is in partnership with VTrans in a project aiming to make roads and highways safer from both its human and wild patrons. Hawkins-Hilke emphasized the dual benefit of proper crossings, bringing up the statistic that 98 vehicle collisions with moose occurred last year in Vermont alone, most of which resulted in death or injury for both parties involved. The 2 year study uses camera traps to determine the areas of frequent wildlife along a stretch of road between Waterbury and Bolton. 
The take-away argument of this article is that because of the necessity following Tropical Storm Irene to better prepare infrastructure for a similar future event, wildlife crossings (specifically culverts) should and could too become more numerous. As more culverts are installed, it only takes a few adjustments to make them suitable for being wildlife crossings as well. 
Habitat fragmentation does not affect wildlife alone. People suffer from this ubiquitous problem too, and unfortunately it is generally not take as a serious problem. Hopefully this project is able to make some progress by piggy-backing on the post-Irene improvements. People need to realize that fixing this issue benefits them as well.


"These culvert improvements really are a win-win for people and wildlife," said Hawkins-Hilke. "They improve the infrastructure, increase food resiliency, and allow wildlife to migrate safely without creating a hazard for drivers."



References
Austin, John. "VTrans, Fish & Wildlife Partner To Improve Wildlife Crossings." VT Digger 22 July 2013. Web. 27 Oct. 2013. <http://vtdigger.org/2013/07/22/vtrans-fish-wildlife-partner-to-improve-wildlife-crossings/>.

-Jessica Mailhot
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Vermont Flagship Species - The Blue Spotted Salamander


As discussed previously, roads are the most commonly seen form of habitat fragmentation in Vermont. This type of fragmentation particularly affects amphibian migration routes to reach vital breeding grounds. The flagship amphibian species here in Vermont is the blue spotted (Jefferson) salamander. Each spring several populations of these salamanders are forced to cross busy roads and highways in order to reach their breeding grounds. As a result, hundreds of adult blue-spotted salamanders are killed by vehicles every year (Page 2010). Eventually the amount of
 mortality on roads will surpass the ability of the populations to replace them which would lead to rapid decline and some populations may even disappear completely . Each year during the salamanders breeding season volunteers work at thirteen site across Vermont to safely carry these salamanders across roads so that they can continue to their breeding sites (Page 2010).  Additionally, in 2010 the state of Vermont award $150,000 to the "Monkton Conservation Commission" to build a culvert under a busy road to provide passage for the salamanders (Richardson 2010). The article from the Washington post provided an interesting insight into a common issue in the conservation world: public opinion and lack of education about conservation issues. The article cited that there was a minor public outcry about spending such a large amount of money on salamander conservation when there is already a budget deficit (Richardson 2010). It went on the explain that the money does not come out of the same budget as money used to, for example, repair highways. Still, it is an interesting to consider how the public views these kinds of projects and how public education on topics of this sort could be more widely available. 


For more information on the Blue Spotted Salamander, click here : 


http://www.burlingtonfreepress.com/article/20100402/NEWS02/112220001/

http://www.washingtontimes.com/news/2010/apr/06/vermont-awards-150000-for-critter-crossing/?page=all

References


Page, C. (2010). "Salamander Crossing in Monkton Wins Grant."Burlington Free Press. Burlingtonfreepress.org, n.d. 



Richardson, V.  (2010). "Vermont Awards $150,000 for Critter Crossing." Washington Times. The Washington Times.
-Neely Fortune
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Forest Fragmentions via Parcelization

This is just an interesting article I found:
"Trends show that forest fragmentation through parcelization (the subdivision of forestland into smaller pieces and multiple ownerships) is gaining momentum. On a regional scale, between 1980 and 2005, approximately 23.8 million acres changed hands in the Northern New England Forest, an area nearly equal to the entire 26 million acre region. The parcelization and fragmentation of Vermont’s forestland has real implications for communities and landowners who want to see the forest for the trees. Vermont’s rural economy thrives on healthy forests that contribute to our tourism industry, recreational opportunities, and the forest products industry. Furthermore, forestlands provide a rich array of ecological functions and wildlife habitats and are vital to maintaining the integrity of our watersheds and water quality."


Read more about forest parcelization in Vermont here: http://www.vtcoverts.org/VTCfiles/Insert_May_08_Newsletter.pdf



-Neely Fortune
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The Genetic Consequences of Habitat Fragmentation: A Review 


Habitat fragmentation reduces the size and increases the spatial isolation of species populations. Initial predictions have been that such changes will be accompanied by an erosion of genetic variation and increased interpopulation genetic divergence due to increased random genetic drift, elevated inbreeding and reduced gene flow. The Journal article Recent habitat fragmentation caused by major roads leads to reduction of gene flow and loss of genetic variability in ground beetles by Irene Keller and Carlo R. Largiander examines the the genetic variation in a population of  ground beetles (Carabus violaccus) that is fragmented by several roads. Although this study did not take place in Vermont, it is relevant to the fragmentation of biodiverse areas due to roads.  A study was conducted in 2000 to determine the genetic isolation of this population of beetles due to roads. Beetles were collected at 10 different sites in a mixed forest near Bern, Switzerland. Test for genetic variability were done on the individuals from each sample site. The results supported the hypothesis that roads have a strong impact on the genetic differentiation of beetle populations (Keller et al. 2003). Furthermore, the comparison of allelic richness between populations showed that genetic variability was lower in populations separated by more then one road. The field data showed that the fragmentation of this species of beetle by roads may lead to local extinction of the species (Keller et al. 2003). Out of the 10 sites sampled, two of the sites had an absence of the beetle. These sites may represent areas were local extinction of the beetle population has already occurred (Keller et al. 2003). The article suggested that future efforts should be made to improve the connectivity of  these habitats.


Read the article here : http://rspb.royalsocietypublishing.org/content/270/1513/417.full.pdf+html



References

Keller, I., & Largiader, C. R. (2003). Recent habitat fragmentation caused by major roads leads to reduction of gene flow and loss of genetic variability in ground beetles. Proceedings of the Royal Society of London. Series B: Biological Sciences270(1513), 417-423.


-Neely Fortune
                                                                                                                                                        

A Different View of Cutting Down Trees: Site visit


In mid November I decided to take and chainsaw safety and techniques course in the Jericho Research Forest. For the course Each student was requires to properly cut down several red pines (Pinus rubra). After telling my friends and family I was taking this course I was met with serval questions that went something like, "I though you loved trees, why would you cut them down," and "Isn't that destroying habitat." What they didn't realize was that part of taking the course involved me specifically selection trees to cut down in order to best benefit the stand of trees. Each tree was selected based on it's crown size and its proximity to the crowns of trees surrounding it. The goal here was to open the canopy enough so that understory trees would benefit, but not so much that they will take over. This ensures a rich biodiversity in the red pine stand. Additionally, because the red pines that were cut down were not removed, they add ground features that provide habitat for animals and fungi. Lastly, core samples from the felled trees will be taken in the spring by forestry students from the University of Vermont to determine the health of the forest of for other learning tools. 

Many people view logging detrimental to habitat and in some cases a cause of habitat fragmentation. However, if environmentally conscious techniques are use (plot thinning as opposed to clear cutting), The removal of larger trees from forest stands can actually be beneficial.

Interested in chainsaw safety classes? Learn more here: http://www.woodlandtraining.com/GOL.php



-Neely Fortune

The Pest Problem

I read an iterating article in this months issue of "Time Magazine." The article basically said that hurt laws are changing to allow hunting within cities "green areas" in order to manage population of mammals such as site tailed deer and wild pigs. This made me think, "are they encroaching on our land, or are we on theirs?"  Hunting may be the easiest form of populations management, but perhaps a focus on habitat management should be considered as well. 
I could not get the full article online but here is a synopsis. See what you think : http://content.time.com/time/magazine/article/0,9171,2158676,00.html

-Neely Fortune

About the Authors
Neely Fortune

Neely Fortune is a senior in the Rubenstein School of Environmental and Natural Resources at the University of Vermont majoring in Wildlife Biology. She spent last spring doing field research in the future Patagonia National Park for Consevacion Patagonica. One of her main projects there involved grassland monitoring of previously fragmented land do to over exploitation and sheep pastoralism. 

Neely grew up in Arizona and later moved to the Adirondack's in upstate New York. She now resides in Burlington Vermont and is currently pursuing and internship with Round River Conservation Studies working with snowmobile and back country skiing recreation's effect on endangered wolverine populations in Idaho. 


Jessica Mailhot

                                                                                                                                                                


References 

Austin, J. (2013) "VTrans, Fish & Wildlife Partner To Improve Wildlife Crossings." VT Digger 22 July 2013. Web. 27 Oct. 2013. <http://vtdigger.org/2013/07/22/vtrans-fish-wildlife-partner-to-improve-wildlife-crossings/>.

Keller, I., & Largiader, C. R. (2003). Recent habitat fragmentation caused by major roads leads to reduction of gene flow and loss of genetic variability in ground beetles. Proceedings of the Royal Society of London. Series B: Biological Sciences270(1513), 417-423.



Page, C. (2010). "Salamander Crossing in Monkton Wins Grant."Burlington Free Press. Burlingtonfreepress.org, n.d. 


Richardson, V.  (2010). "Vermont Awards $150,000 for Critter Crossing." Washington Times. The Washington Times.
www.washingtontimes.com/news/2010/apr/06/vermont-awards-150000-for-critter-crossing/?page=all


van der Ree, R., J. A. G. Jaeger, E. A. van der Grift, and A. P. Clevenger. (2011). Effects of roads and traffic on wildlife populations and landscape function: road ecology is moving towards larger scales. Ecology and Society 16(1): 48.  http://www.ecologyandsociety.org/vol16/iss1/art48



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