Fecal Samples Indicate Stress Levels in Wildlife Conservation Projects.

Franceschini, M.D., Rubenstein, D.I., Low, B. and Romero, L.M. 2008.Fecal glucocorticoid metabolite analysis as an indicator of stress during translocation and acclimation in an endangered large mammal, the Grevy’s zebra. Animal Conservation 11: 263-269.

Link: http://onlinelibrary.wiley.com.ezproxy.tru.ca/doi/10.1111/j.1469-1795.2008.00175.x/pdf

                Stress in animals is complex and there is a limited variety of non-invasive methods to monitor stress levels especially with endangered species. Monitoring the stress response in species that undergo conservation projects is crucial in indicating the overall success of the projects. Animals that are chronically stressed are typically more susceptible to developing diseases and reproductive output can be restricted. Translocation, reintroduction and rehabilitation practices aim to re-populate endangered species. Guidance in regards to these methods of re-population is important to determine the least stressful approaches (Franceschini 2008). The least stressful approach would entail the least amount of human handling/disturbance in the species’ natural environment, and the optimal duration of captivity. 

            Fecal glucocorticoid metabolite (FGM) analyses provide very effective means for detecting the concentration of adrenocorticotropin (ACTH) in mammalian species. It is accurate, non-invasive, can be obtained after the animal fleas the scene, and is versatile in its application. FGM measurements have been used in several wildlife projects such as, social interactions and status, anesthetic procedures, anthropogenic activity, radio-transmitters, zoo/captive lifestyle and environmental enrichment (Franceschini 2008). As part of a re-population project, park managers of the Meru National Park in Kenya monitored FGM levels during a translocation project in an attempt to determine just how stressful a translocation project can be for the endangered species at hand, the Grevy’s zebra. A small population of zebras was translocated from a privately owned park (Lewa Downs just north of Mount Kenya) to Meru Park, in which only two zebras were present at the time. The project followed strict guidelines and FGM samples were compared to a control group consisting of non-translocated zebras. Opportunistic fecal samples from the small population were taken just after tranquilization of the mammals, during captivity, and pre and post release. 

            The results identified that concentrations of FGM were highest during captivity (indicating a very stressful period) and the concentration returned to pre-capture levels during post release, indicating successful acclimation and translocation. Even though FGM analyses are accurate in detecting changes physiologically and biochemically, it does not give information about long-term survival and reproductive abilities in the translocated species. FGM is a promising tool in assessing amount of enrichment in the lives of captive animals, the best approach to translocation involving the least amount of stress, and the health of wild populations (Franceschini 2008).

Words: 383

An Example Situation of Invasive Species Control in National Parks

Mack, R.N., Simberloff, D., Lonsdale, W.M., Evans, H., Clout, M., and Bazazz, F.A. 2000. Biotic invasions: causes, epidemiology, global consequences, and control. Ecological Applications 10:689-710.

Link: http://www.jstor.org.ezproxy.tru.ca/stable/pdfplus/2641039.pdf?acceptTC=true

Hickey, V. 2010. The quagga mussel crisis at Lake Mead National Recreational Area, Nevada (U.S.A.). Conservation Biology 24:931-937.

Link: http://onlinelibrary.wiley.com.ezproxy.tru.ca/doi/10.1111/j.1523-1739.2010.01490.x/pdf

Many parks are typically established with competing mandates that involve serving people as well as conserving nature. The rivalry of these mandates can become the culprit of many problems. Humans directly benefit from conservation efforts though it seems that anthropogenic activity typically results in obstruction of conservation efforts and as a result natural ecosystem flow and ecological service to humans is negatively impacted. With this said, it is easy to see that these competing mandates can be incompatible and uncomplimentary to one another and detrimental effects subsequently arise. An example of a park that was established on the basis of these mandates is Lake Mead National Recreational Area in Southwestern United States.

Lake Mead Park is a reservoir originally established as land set aside after the construction of Hoover Dam in 1936. In 1953, Lake Mohave was also created as a reservoir from another hydroelectric station and together these lakes were assigned as preserved land and a recreational area in 1964 (Hickey, 2010). The purpose of the park was to provide water recreation opportunities for present and future generations in a manner that will preserve the scenic, historic, scientific, and other important features of the area. This purpose seems to convey that ecological services to humans is of first priority, but with this said future recreation depends on softening the impacts of human activities to conservation nature as much as possible. Therefore natural conservation is of second if not of equal importance to ecological services. Lake Mead Park is a prime example of serious problem arising from competing mandates. As a result of adhering to the parks purpose and implemented orders, Lake Mead Park managers failed in regards to the containment, management, prevention, and treatment of non-native invasive species. In other words, the invasive quagga mussel (Dreissena rostriformis bugensis) epidemic was not dealt with sufficiently when efforts to meet both public and conservationist’s needs were not enough to prevent the problem.

The quagga mussel is a subspecies of freshwater mussel that is 1 of the 7 Dreissena species. It is native to the Dneiper river drainage of Ukraine and it was thought to be first introduced to the United States in Lake St. Clair (near Detroit, Michigan) in 1988 (Hickey, 2010). Because basic scientific information of Dreissena is incomplete and there is a lack of existing data on environmentally safe and effective control, four options were discussed in order to deal with the mussel outbreak. These options included doing nothing, closing off the park to vessels, prevention of vessels traveling to different parts of Lake Mead, and educating and enforcing regulations. The option of doing nothing was out of the question as it did not comply with its mandate to preserve the ecosystem in its natural state. Closing off the parks to vessels also violated the human recreation mandate. Preventing the travel of vessels to different parts of Lake Mead, and therefore slowing colonization, did not make sense when the turbulent water from Hoover Dam’s intake pipes did not prevent the colonization of adult mussels and veligers (mollusk larva) downstream. Furthermore, this prevention of vessel travel is likely very difficult despite financing due to the open-accessibility and large size of the park and its numerous launching sites which would require numerous law-enforcement agents. However, to some degree this option was followed via park zoning (restricting recreational activity and other land uses to particular locations within the park, leaving other areas undisturbed). It was decided that the last option, to educate public and enforce regulations, would be the major effective mode of treatment without violating park mandates.

There was a huge amount of support and funding available to the education and law-enforcement program as many urban and agricultural communities, as well as several migratory birds and propagating, endangered fish species, depend on the Lakes for freshwater. Furthermore, the Park’s water feeds into hydroelectric stations, is supplied to many industries, and is the sole source of drinking water to some 55 million residents and tourists. The education and regulation enforcement project involved inspection, decontamination (cleaning, draining, and drying of vessels), and monitoring of traveling vessels from different parts of the lake. In addition, the team produced signs in high human activity areas of the park explaining the ecological effects of the invasive species and associated boat operation and maintenance costs (Hickey, 2010).

The detrimental effects of the over abundance of quagga mussels can clog water intake structures, remove phytoplankton (which zooplankton depend on and in turn higher trophic levels), increase water clarity (which results in increased light penetration to aquatic plants and alters the composition of dominant species), raise the acidity of water as their pseudofeces decompose, and increase the exposure of their predators to increased amounts of organic pollutants within the mussel’s tissues (Hickey, 2010).

Despite the parks efforts to prevent the outbreak of Dreissena rostriformis bugensis via its early detection program and its sufficiently funded education and law-enforcement project, quagga mussels now thrive in Lake Mead Park and the lake continues to be responsible for some degree of the mussel spread. The park is now experiencing large financial and conservational losses involving decreased human recreational satisfaction, damage to vessels and water treatment plants, and alteration of natural fauna and flora. Notably, the Park’s zoning technique (which was established to form a compromise between conservation and human use) seemed to have magnified the issue by creating an efficient pathway for invasion. With restricted access to several parts of the park, humans were concentrated and forced to use similar pathways to enter and exit the park. These pathways as a result repeatedly imported and exported invasive species that which exploited the natural resources of that area. In turn the exploited areas act as an effective reservoir to help spread the thriving mussel to several different areas. Zones aren’t a great idea, and at the very least they could be used as a buffer zone between disturbed and undisturbed areas. It is within these zones that extensive effort must be put towards prevention.

There is documentation that suggests where conservation efforts, in such an example of Lake Mead Park, could have been successful in detecting and preventing invasion. For instance, during contamination for vessels traveling from one part of the lake to another, it is not the efficacy of the tools themselves that are responsible for controlling the abundance of an invasive species but rather the commitment and diligence of park managers. Furthermore, parks in general need to execute ecosystem wide strategies and long term goals rather than employing quick fixes and focusing on one species (Mack, 2000). This mind/goal set will conserve funds by directing money towards prevention rather than the more expensive alternative of post-entry control (Mack, 2000). The attributes that indicate whether or not a species will become invasive are inconclusive as species are so different from one another. In addition to this statement, it is also difficult to determine where and when a species will become invasive especially when most introductions do not result in invasiveness due to unfavorable environments and temporal variations (Mack, 2000). Overall, careful management towards prevention of invasiveness is crucial in avoiding sever global consequences.

Words:1190

Eastern Gray Squirrel as an invasive species

Gonzales, E. 2005. The distribution and habitat selection of introduced Eastern Grey Squirrels, Sciurus carolinensis, in British Columbia. Canadian Field-Naturalist, 119(3): 343-350.

(This peer reviewed article is not available online so no link, sorry)

The Eastern Gray squirrel was first introduced to Vancouver B.C. in the early 1900’s and soon after it thrived. The Gray squirrel inhabits deciduous forests typically filled with nut producing trees like oaks, hickories and chestnuts. They also prosper in residential areas, parks and cemeteries.  There has been concern as to whether or not these Gray squirrels are displacing native squirrel species, but the explanation for non-native and native squirrel species’ abundance is understudied. Further analysis will identify whether the culprit to the native species’ decline is competitive exclusion via interspecific interaction, or habitat modification upon forest fragmentation.

The Eastern Gray squirrel and several native squirrels have been known to co-exist in Vancouver over many years because of habitat segregation. Native squirrels typically inhabit coniferous forests and are more sensitive to anthropogenic activity than the Gray squirrel. Upon forestation it is the coniferous forests that commonly become logged and these areas are reconstructed into residential areas with deciduous trees. It was discovered that the Gray squirrel was very successful in human modified environments. Nesting was found in houses and trees and food was easily accessed through gardens, bird-feeders, garbage, and handouts. In order to control the ever growing population of Gray squirrels conifer forests must be maintained and large seed deciduous trees must be planted less frequently in these areas. It has also been suggested that large populations of Gray squirrels are detrimental to native, young Garry oak species as the squirrels frequently strip the plant’s bark. 

So, it is not the Eastern Gray squirrel that directly impacts native species’ persistence through competition of resources, but rather as development continues the native species’ population size declines due to loss of habitat as the invasive species’ habitat is favored and increases rapidly in response. These species will be able to co-exist further if sufficient suitable habitat is available for both natives and non-natives.


Words: 312

An Eden for Sharks

Holland, J. 2007. Blue waters of the Bahamas: An eden for sharks. National Geographic Magazine 211:116-137.

http://ngm.nationalgeographic.com/2007/03/bahamian-sharks/holland-text/1

The Article “Blue waters of the Bahamas, is about the very valuable, diverse habitat that the Caribbean provides for numerous species to thrive in. With its combination of reefs, sandy beaches, mangroves, lagoons, grass beds and sheer drops amid shallow waters, this heterogeneous environment is a nursery for several species of sharks to reside in. Because sharks continue to carry a bad reputation due to the images media portrays, research dollars and public support is hard to come by. With the Bahamas still being a young country, they too need to learn their own mistakes and successes regarding the very fine line between development and ecological protection.

To expand on the description of the fine line, the Bahamians depend on tourists to bring in half of the gross national product. In order to keep enticing fishing and diving visitors, development must be present as well as a beautifully diverse ecosystem, but there needs to be a balance involving gentle development that attracts manageable amounts of tourists and preservation of sharks in their ecosystem.  What people don’t realize is that sharks are valuable in that they individually bring in $200,000 each in tourism revenue over a lifetime, in addition they are a keystone species that if depleted would not keep other carnivores in check that in turn would reduce the abundance of algae-eating fish that keep coral reefs healthy. Sharks also weed out weak and sick fish only to provide the most fit and healthy fish to the locals.

On top of habitat loss to numerous species of sharks, 73 million die annually to worldwide shark finning which is illegal, cruel and very wasteful. Commercial fishing also contributes to unintended as well as targeted captures of millions of sharks. This is very unsettling and to add to all this sharks have slow reproductive rates. With the development of more marine sanctuaries and complementary strict enforcement, sharks and their most bountiful ecosystems can be preserved to feed local people and keep visitors coming to support what they love to experience.

Words: 355

A world without mosquitoes

Fang, J. 2010. A world without mosquitoes. Nature 466: 432-434. doi:10.1038/466432a
http://www.nature.com/news/2010/100721/full/466432a.html

In summary, the article “A world without mosquitoes” essentially explains the one major downfall of having mosquitoes around as well as the many consequences that would arise if they were not around. Of course the world would be a much healthier place if the major disease vectors were eliminated, but in contrast mosquitoes are prey to many predators, are predators to various organisms, pollinate numerous plants, and form important symbiotic relationships with several organisms.

The ecology article is naïve, extremely biased, and goes against well understood guidelines of conservation biology.  The article is extremely biased not only because we overestimate the abundance of mosquitoes due to their selective attraction to us but we can’t help but view the negative effects of their existence because of what they are doing to the human race.  According to years of experimental study, to alter one organism’s abundance is to alter many other organisms’ chance of persistence, and only when populations are severely endangered and extensive research has been carried out are these measures ever taken. It is out of our ignorance to say that mosquitoes are useless in this world. As Aldo Leopold once said, “if the land mechanism as a whole is good, then every part is good, whether we understand it or not”. So, why sacrifice many species’ persistence for the security of one species when that one species population size is far from being threatened? In addition, aren’t enough species going extinct because of our influence, and are we the culprit for their ever growing population size? Why eradicate more species for an insufficient reason? The biggest consequence of not eliminating mosquitoes is simply that there would be too many humans to exploit the already depleted natural resources of this world. The costs of an increased population would far outweigh the benefits of a healthy population. So, we can now look at mosquitoes as organisms that keep the human population in check.