The Green Wall of……Grazers?!

Desertification is a process of land degradation whereby environments become increasingly arid and loose productivity over time [2]. Desertification occurs when land surfaces are transformed by human activities, including overgrazing, deforestation, surface land mining, and poor irrigation techniques. Desertification in the Sahel region of Africa is mainly attributed to an increase in human activity and their grazing livestock.

For a long time it was thought that the major factor causing desertification was the over grazing of livestock. This led to strict land use policies and a shift from livestock and wildlife coexisting on the landscape to a complete separation in an attempt to curb the effects of desertification. Wildlife became increasingly concentrated on nature reserves and due to land fragmentation, livestock was held on smaller land plots [4]. Yet it seemed as though the land began to get drier each year with less and less vegetation returning.

As the seriousness of desertification began to reach a global stage, many suggestions have been made as to how to stop such a process. One idea is to grow a wall of trees that stretches across the entire southern boundary of the Sahara desert, known as the Great Green Wall [3]. The idea being that setting up a natural barrier to desertification would reduce wind speed, stabilize the soil and increase soil humidity, halting or even reversing the process. Mainly due to a lack of global support as well as little local representation, the Great Green Wall has been a slow process. This initiative has also been contested as it could lead to unforeseen problems down the road. Concerns regarding water use are most often cited; the Sahel region is an arid landscape and there may not be enough water to grow such a large wall of trees [3].

If restricting grazing only makes things worse and no one is willing to spearhead a large intervention event such as the Great Green Wall, what can be done? One solution that has been proposed is to not restrict grazing but rather release it. Using livestock to mimic the grazing behaviors once carried out by native herds, which have since been reduced due to human encroachment and land fragmentation, would encourage natural turnover of grasslands and sustain a healthy environment [1]. How does this happen? Desertification occurring in arid lands sees seasonal changes in the environment with a hot dry season and a wet growing season. Grass grows really fast during the wet season, but as things become drier the plant biomass above ground dies. These dead plants need to decay biologically and quickly so that new plants can grow during the next season. However, when large herds of grazers are absent, the dead material shifts from rapid biological decay to gradual breakdown through oxidation and weathering. This leads to dead plant material blocking light from reaching the soil and prevents new plant growth. If there is enough rain, grasslands shift to shrubs and trees, but when rainwater is scarce, they shift to bare, generally algae-covered soil and small woody bushes. As space between plants increases, the effectiveness of rainfall decreases. Rain that soaks into the soil evaporates back out. Or, in the case of extreme rain, most of the water runs off, causing flooding. Using large herds in combination with planned grazing patterns to mimic natural cycles will eventually start to restore the land and allow for it to become self-sustaining.

 

-Scott Morton

 

 

Works Cited:

  1. Savory, Allan (1983). The Savory Grazing Method or Holistic Resource Management. Rangelands. 5(4)
  2. http://earthobservatory.nasa.gov/Features/Desertification/
  3. O’Connor, D. and Ford, J. (2014). Increasing the Effectiveness of the “Great Green Wall” as an Adaptation to the Effects of Climate Change and Desertification in the Sahel. Sustainability. 6:7142-7154.
  4. Hobbs et al. (2008). Fragmentation of rangelands: Implications for humans, animals, and landscapes. Global Environmental Change-Human and Policy Dimensions. 18: 776-785.

 

 

The Lead Stops Here

The use of lead shot for hunting and sport shooting has caused major problems for upland foraging birds (Raptors). Raptors are predatory birds that use their feet and talons to catch and kill their prey. Recently, I started volunteering at the Rocky Mountain Raptor Program (RMRP), which is a non-profit organization that provides medical care and rehabilitation to these birds. In a two month period I witnessed three Raptors who were brought to our facility suffering from lead poisoning, of which only one survived and was able to be released after undergoing extensive chelation treatment. After seeing the effect of lead first hand, I wanted to know more about how these birds were becoming poisoned and how can we prevent this from happening in the future.

Animals can be exposed to lead in many ways: mines, smelting plants, harbors, industrial areas, urban areas and leaded petrol combustion [3]. Hunting with lead shot is the primary cause of lead toxicity in raptors due to their foraging behavior. Raptors are obligate carnivores who are able to get all of their water and nutrients from meat. They also exhibit generalist and opportunistic feeding behavior so when they see a gut pile left behind by a hunter they will take full advantage of this tasty treat. This type of foraging behavior causes raptors to inevitably ingest lead that is left behind in gut piles, lost or un-retrieved game, and when capturing wounded animals who have shot embedded in their tissues [2]. Once in the system the lead is rapidly dissolved by the low pH of the stomach and absorbed into the bloodstream [4]. Lead accumulates in the kidneys, liver, brain and most of all in the bones due to its long biological half-life. Lead also has the ability to disguise itself as other metals and be taken up into the cells more readily. Lead disrupts important biological processes such as DNA transcription and enzymatic pathways [1]. High accumulation of lead in  bone is a result of exposure to low concentrations over long periods of time, which can cause mineralization of the bones in adult birds [5].

Symptoms of lead poisoning can be seen immediately in raptors and include distension of the proventriculus, green watery feces, weight loss, anemia and drooping posture [4]. It can also affect the nervous system and become detrimental to biochemical functions causing blindness, depression of certain blood enzymes, reduced reproduction, and impaired immune function [4]. Furthermore, it can result in behavioral changes that make raptors prone to predation, which results in higher mortality rates [4]. This is of direct conservation concern because many raptors are long-lived, slow breeding species with small populations like the California condor. In a study done by Clark and Scheuhammer on lead poisoning in upland foraging birds in Canada, four deaths of reintroduced California condors were directly attributed to leftover lead shot in deer carcasses [3].

Size, age, and proximity to human activity have monumental influences on the distribution of lead in a bird’s tissue. The bigger the bird the more energy it needs to take in and, therefore, they ingest large amounts of meat, which gives them a higher probability of ingesting lead than smaller raptors [3]. Figure 1 on the left is taken from a study done on lead exposure in four different raptor species from Spain [3]. It shows that lead concentrations have a direct correlation to the size of the bird, which are listed as follows from largest to smallest; Eagle Owl > Buzzard > Kestrel > Little Owl. The reason for the low concentrations found in the buzzard compared to its size, as opposed to the smaller two raptors, can be attributed to the fact that the European buzzard inhabits places with low human activity.

Hunting season also plays a factor in lead exposure in large birds of prey [1]. Human activity is the main source of environmental lead and is why these birds are becoming poisoned; the closer raptors are to human activity (hunting, sport shooting, etc.) the higher the lead concentrations found in the bloodstream [4]. With the human population growing at an exponential rate, small towns will expand into urban and industrial areas. This will increase human contact with wildlife populations which, in turn will increase raptor exposure to lead shot.

Lead has been shown to cause long term detrimental effects on humans and mammals [5]. It is a highly toxic heavy metal that can be released into the environment in many ways. Acute exposure (high concentrations over short time) in vertebrates can lead to death, while chronic exposure can affect reproductive success, behavior, physiological and immune responses [5]. Lead may be a cheaper alternative for ammunition but the effects it has on wildlife is very expensive. It’s not just raptors that are of concern here, other species of birds have also been known to suffer from lead poisoning due to lead shot left behind from sport shooting or hunting. These species of birds mistakenly pick up lead pellets along with grit for their gizzards. This has been seen in species like whooping cranes, sandhill cranes, Virginia rails and even a wild turkey [4]. In 1991, the use of lead shot on waterfowl was made illegal in the United States. Since then, alternative forms of non-toxic shot have been introduced and approved for waterfowl that can also be used on upland game [4].

The most obvious solution for this growing problem would be to ban the use of lead bullets and replace them with a form of non-toxic pellets. We could also follow the lead of Britain, Australia, Sweden, Denmark, Norway, Finland and the Netherlands in establishing restrictions on the use of lead for hunting. Lead free zones can be established in places like breeding grounds and migratory rest stops that are important to wildlife. All of these alternatives are feasible and can be implemented with very little repercussion to us. For the future of our raptors and other bird species, something needs to be done soon before it is too late.

Works Cited:

[1] Clark, A. J., and A. M. Scherhammer. “Lead Poisoning in Upland-foraging Birds of Prey in Canada.” Ecotoxicology 4th ser. 12.1 (2003): 23-30. Web of Science. Web. 20 Mar. 2015.

[2] Custer, Thomas W., J. Christian Franson, and Oliver H. Pattee. “Tissue Lead Distribution and Hematologic Effects In American Kestrels (Falco Sparverius L.) Fed Biologically Incorporated Lead.” Journal of Wildlife Diseases 20.1 (1984): 39-43. Web of Science. Web. 20 Mar. 2015.

[3] Fisher, Ian J., Deborah J. Pain, and Vernon G. Thomas. “A Review of Lead Poisoning from Ammunition Sources in Terrestrial Birds.” Biological Conservation 131.3 (2006): 421-32. Web of Science. Web. 20 Mar. 2015.

[4] Gangoso, Laura, Pedro Álvarez-Lloret, Alejandro. A.B. Rodríguez-Navarro, Rafael Mateo, Fernando Hiraldo, and José Antonio Donázar. “Long-term Effects of Lead Poisoning on Bone Mineralization in Vultures Exposed to Ammunition Sources.” Environmental Pollution 157.2 (2009): 569-74. Web of Science. Web. 20 Mar. 2015.

[5] García-Fernández, A. J., M. Motas-Guzmán, I. Navas, P. María-Mojica, A. Luna, and J. A. Sánchez-García. “Environmental Exposure and Distribution of Lead in Four Species of Raptors in Southeastern Spain.” Archives of Environmental Contamination and Toxicology 33.1 (1997): 76-82. Web of Science. Web. 20 Mar. 2015.

 

Derwent Estuary, the Finest Sea Star Hotel

The world thrives on life’s diversity. Every natural space or ecosystem is filled with a variety of organisms that together work to keep the earth in its natural cycle. This natural cycle is rather delicate, and if parts of the puzzle are absent, the whole system does not work as well. One example of this is when a pivotal or keystone species is taken out of an ecosystem (by extinction for instance) and alters the ecosystem by disrupting the food web or natural order of the habitat. Species can be eliminated by natural and unnatural causes. Some unnatural causes include urbanization, human disturbances, hunting and poaching, and invasive species inhabitation.

Invasive species can come about as a result of human disturbance activity. These disturbance activities include people picking up and moving species to a different place, or animals attaching themselves to transportation vessels and traveling large distances, ending up in an environment they are not native to. One example of this is found in the Derwent Estuary in Tasmania, where millions of Northern-Pacific sea stars have moved into and overtaken the waterway. These sea stars are native to Northern Pacific areas such as Japan, and because ocean currents do not naturally carry them down to Australia, it is thought that some sea stars in larval stages were sucked up and carried by harboring ships to the Tasmanian shores, thus they are classified as an invasive species [1].

In a study published in The Journal of Applied Ecology, it was found that the feeding and breeding habits of these sea stars make them particularly successful in the Derwent Estuary [1]. The Northern-Pacific sea stars feed on bivalves (clams, mussels, scallops, etc.) and reproduce by external fertilization (expelling sperm and eggs out into the water to be fertilized). Due to the Derwent Estuary having an abundance of manmade docks, jetties and piers in the water, there is plenty of available substrate for bivalves to latch on to and filter feed. This provides the sea stars with an abundance of food in a very concentrated area. Not only do they thrive on the food source, but also the close vicinity of the docks provides a convenient space for the sea stars to expel their eggs and sperm into the water to be readily fertilized by other sea stars in the area. The overabundance of sea stars in their non-native environment significantly depletes the native species (assortment of bivalves) that are typically found there. In this way, the human construction of docking structures has facilitated an explosion of this invasive species population, and significantly decreased biodiversity.

With our knowledge of the causes and consequences of this problem, we have the opportunity to solve it. One approach would be reducing the availability of the food source for the sea stars by either displacing or blocking off the mussels and clams attached to docking areas. This could be done by fencing off the docking substrate (after the bivalves have established themselves) so the sea stars can’t reach the bivalves. Another potential solution would be changing the structure of the docks so that they are non-attachable for sea stars, or so they are more spread out, making external fertilization less effective to slow their reproduction. Another approach being tested is the implication of ciliates that parasitize the male gonads. Introducing these parasites may be effective in controlling the reproductive rates of the invasive sea stars. Research would have to be done to ensure that the ciliate species is specific to the targeted invasive species and would not be detrimental to other species in the ecosystem.

Basically any method to decrease the numbers of sea stars will help to keep the bivalve populations at normal levels and sustain the biodiversity in the ecosystem. It is very important for diversity to thrive in any ecosystem because, if the natural order of things is thrown off, it is very hard to recover it by natural or artificial means. Halting the cause of what sparks invasive species populations can help control them before they get bad, and ultimately help preserve biodiversity.

–Cristiana Falvo
[1] Ling, S. D., Johnson, C. R., Mundy, C. N., Morris, A. and Ross, D. J. (2012), Hotspots of exotic free-spawning sex: man-made environment facilitates success of an invasive seastar. Journal of Applied Ecology, 49: 733–741.

[2] Bouland, Catherine and Goggin, Louise. The ciliate Orchitophrya cf. stellarum and other parasites and commensals of the northern pacific seastar Asterias amurensis from Japan. International Journal for Parasitology, vol 27; p 1415-1418.

Can Human Hunters become a Natural Part of the Ecosystem?

Who doesn’t love nature?  The fresh air blowing through the trees, the sweet songs of birds and frogs, and the absolute feeling of being free.  The chance to see a female deer and its fawn excite even the most urbanized kid and seeing a real life equivalents of Chip and Dale chasing each other would make anyone laugh.  Those who have worked with or have been in nature know that when nature is in balance, things work out beautifully for both man and nature.

But nature is not entirely balanced these days.

Despite the pristine appearance of our natural areas, there is a problem happening within.  Deer and elk have been visiting the riparian areas (where land and water meet) of streams, rivers, and lakes more often than they had before and have been consuming more than their fair share of sapling trees.  Why is this all bad?  Well, with the deer and elk visiting the riparian areas more often, they are consuming the sodium-rich plants that are essential to control soil erosion.  Studies have shown that with this combination of less plant life and more soil erosion, the deer’s and elk’s actions are destroying habitats for fish and amphibians by making the waters murky with sediment.  These sediments negatively affect farms as well [3].  This also has negative effects on local bird populations by modifying their breeding patterns [6].  And what about the lack of sapling trees?  With the lack of sapling trees, there are less and less trees to replace the older trees when they die of age, disease, parasites, or wildfires.

Why has this happened?  Three words: Lack of predators.

While it no secret that predators are important in controlling the population size of prey species, they are also important for other components of the ecosystem as well.  Along with eating their prey, they also influence their prey’s behavior.  Studies in Yellowstone have shown that following the reintroduction of the wolves, local elk population’s modified their behavior whereby they visit the riparian areas less often [1, 10] and browse less on sapling trees [9].  This is likely because sources of water are a popular place for predators to hunt and their presence has kept the prey moving often, not staying in one location for an extended period of time.

So it seems that predators are a sort of silver bullet to this issue.  But there is a problem with using predators to control prey.

A good number of places that suffer these sorts of habitat disturbances as in areas where there is not enough room to support large predators or they are too close to urbanized areas.  There is no doubt that no one would want large predators reintroduced right in their back yards, especially if their children might become targets for the would-be predators.

So if not large predators, what is the alternative?

Human hunters.

I would propose incorporating human hunters into areas that are close to urban areas or are too small to support large predators but suffering with riparian area destruction due to browsing by local wildlife.  Human hunters not only control prey populations, but also manipulate their behavior in a similar way as larger predators.  There have been studies that have shown that human hunting can be an alternative to a predator stimuli [5].  Human hunting has influenced deer behavior enough to give deer appropriate flight responses [12], influenced their browsing behavior to allow tree regeneration [8], and even made them roam at greater distances [11].  I would propose that we shall allow hunters to hunt at specific locations (e.g. heavily-used riparian areas and areas where tree saplings are being over-browsed) to stimulate these sorts of fear responses and allow the ecosystem to recover while also allowing them to be safe in other areas that are in need of more deer activity.

This is a solution that I believe would help the environment and it would definitely get some support from the hunting community.  But I fear that it won’t get a great deal of support.

Why?

Public opinion.

We’ve all grown up with Disney’s Bambi and with the negative public perception and opinion of hunting [4].  With this and animal rights groups like PETA obviously against it, it would be either really hard or near impossible to have this plan gain traction.  How could we get over this obstacle?  How would you get people to properly understand that this is a conservation movement?  Through proper education.  Hopefully, through proper education, we can teach people that this sort of hunting movement is vitally important for the wildlife, their habitats, and their ecosystem.  Also, we may need to emphasize that human hunting of wildlife is safer in those areas than reintroducing large predators.  For this is safer for the people and the animals.

Some would say that hunting is not good for nature, but I say to that as Aldo Leopold once said, “A thing is right when it tends to preserve the integrity, stability and beauty of the biotic community. It is wrong when it tends otherwise.”[7]

-Austin Major

Works References

  1. Beschta, Robert L., and William J. Ripple. “The role of large predators in maintaining riparian plant communities and river morphology.” Geomorphology 157 (2012): 88-98.
  2. Côté, Steeve D., et al. “Ecological impacts of deer overabundance.” Annual Review of Ecology, Evolution, and Systematics (2004): 113-147.
  3. Cooper, J. R., et al. “Riparian areas as filters for agricultural sediment.” Soil Science Society of America Journal 51.2 (1987): 416-420.
  4. Decker, Daniel J., and Tommy L. Brown. “How Animal Rightists View the” Wildlife Management: Hunting System”.” Wildlife Society Bulletin (1987): 599-602.
  5. Frid, Alejandro, and Lawrence M. Dill. “Human-caused disturbance stimuli as a form of predation risk.” Conservation Ecology 6.1 (2002): 11.
  6. Kauffman, J. Boone, and William C. Krueger. “Livestock impacts on riparian ecosystems and streamside management implications… a review.” Journal of range management (1984): 430-438.
  7. Leopold, Aldo. 1966. A Sand County Almanac: With Other Essays On Conservation from Round River. Oxford University Press. New York, NY. 269 p
  8. Martin, Jean-Louis, and Christophe Baltzinger. “Interaction among deer browsing, hunting, and tree regeneration.” Canadian Journal of Forest Research 32.7 (2002): 1254-1264.
  9. Ripple, William J., and Robert L. Beschta. “Restoring Yellowstone’s aspen with wolves.” Biological Conservation 138.3 (2007): 514-519.
  10. Ripple, William J., and Robert L. Beschta. “Wolves and the ecology of fear: can predation risk structure ecosystems?.” BioScience 54.8 (2004): 755-766.
  11. Root, Brian G., Erik K. Fritzell, and Norbert F. Giessman. “Effects of intensive hunting on white-tailed deer movement.” Wildlife Society Bulletin (1988): 145-151.
  12. Stankowich, Theodore. “Ungulate flight responses to human disturbance: a review and meta-analysis.” Biological Conservation 141.9 (2008): 2159-2173.
  13. Stromayer, Karl AK, and Robert J. Warren. “Are overabundant deer herds in the eastern United States creating alternate stable states in forest plant communities?.” Wildlife Society Bulletin (1997): 227-234.

Free Birth Control for Wild Horses

The wild or feral horses of the American plains are a hot topic for conservationists, ranchers, and the public at large. Ranchers would like for the horses to disappear because they compete with their cattle for grazing on public lands. The horses are an introduced species, brought here by the Spanish in the late 1400’s. This means they are not a native species and so some think they’re not worthy of protection. Here’s the twist, equines actually evolved in North America, dying out at the end of the last ice age, potentially at the hand of humans. So do they deserve a place in the ecosystem of the North American plains? Or should they be eradicated as a feral pest species?

The one thing that everyone can agree on is that the wild horse population must be kept in check. They have no real predators and there are limited resources available for them so if humans do not manage them they will become overpopulated and starve. Historically the methods of culling the herds have ranged from barbaric to, the public pleasing, rounding them up and adopting them out. The agency that manages the wild horses is the Bureau of Land Management, or BLM. But the BLM can’t keep up with the reproductive rate of the horses and the public has made it very clear that they do not want these horses hunted or slaughtered. So another idea is being tried.

The Porcine Zona Pellucida vaccine is a contraceptive that is being used on the horses. It works by introducing proteins extracted from pig eggs, include what is thought to be the sperm receptor, into the horses systems. This causes the animal to produce antibodies that target sperm, thus preventing the ova from being fertilized [3]. The PZP vaccine has proven to be effective in horses for only two years, which is less than ideal. This limitation has prevented the application of the vaccine to whole herds and caused the BLM to focus on animals being released after being caught. The BLM is funding more research to try and make a longer lasting vaccine, and potentially one that is easier to administer because trapping the horses in order to give them the contraceptive is stressful and expensive, and darting them with vaccines is difficult [1].

One potential cause for concern is that PZP could alter the behavior of the mares. Luckily the vaccine doesn’t alter the hormone levels of the mares like most contraceptives do [2]. A study was done in 1997 on wild ponies on Assateague Island to see if their behavior changed. They looked at the activity budget of the mares, their interactions with the stallions, and their aggressive encounters with other horses. The findings were that there were no statistical differences between the treated mares and the untreated mares and that the PZP caused no change in their behavior [4]. This is good news for managers concerned with how the contraceptive could impact the natural behaviors of the horses.

My conclusion on this topic is that there is potential for PZP for help control horse populations. But in order for it to be cost effective and not too stressful for the animals, we’ve got to find a way to make it last longer. This may mean looking for another drug to use or improving this one. In the meantime I think that managers should continue to give PZP to horses that are captured and released for other reasons. It can only help slow the population growth to do so and the populations will benefit.

 

References

 

1.“Fertility Control.” US Department of the Interior Bureau of Land Management. http://www.blm.gov/wo/st/en/prog/whbprogram/science_and_research/fertility_control.html

 

  1. Kirkpatrick, J. F., Liu, I. K. M., and J. W. Turner. “Contraception of Wild and Feral Equids. Oct. 1993. USDA National Wildlife Research Center Symposia. http://digitalcommons.unl.edu/nwrccontraception/15/

 

  1. “Porcine Zona Pellucida Vaccine.” PNC project for Wildlife Contraception. http://www.pzpinfo.org/pzp.html

 

  1. Powell, David. “Preliminary Evaluation of Porcine Zona Pellucida (PZP) Immunocontraception for Behavioral Effects in Feral Horses (Equus caballus).” 1999. Journal of Applied Animal Welfare Science.  http://www.tandfonline.com/doi/abs/10.1207/s15327604jaws0204_6#.VRoar44sp9m

Rethinking Exotic Pet Ownership

python

Imagine you’re a snake lover, and while online shopping you come across this advertisement, what is the first thing you think? Do you respond as a buyer?

Tiger

After awhile on the same sight, you come across the sale of this eccentric species. Do your opinions change as a conservationist?

 

Personally, I don’t agree with the sale of big cats for private ownership. I would be willing to bet most of my conservation-concerned peers don’t either. However, the sale of a python doesn’t particularly baffle me. But I ask myself, what is the difference? Exotic trade animals aren’t limited to oversized mammals such as tigers and monkeys. Exotic animals include “normal” pets such as rabbits, birds, and snakes. Although as a result of careless private ownership, the Burmese python (shown for sale in image 1) is threatening native species in the Everglades [1].  This is only a single example of a conservation issue created by an animal that some would consider a standard pet. While most pet owners do not own 7-foot snakes, I don’t presume there are many people that would be outraged at by the knowledge of a friend having one – it is legal after all. There are only 21 states that have complete bans on exotic pets; The other 29 states have partial bans, license permitting, or no regulation at all for these animals [2]. The complete bans are variable by state, so each state has different standards on the animals they consider exotic. This indicates that there is no national or international agreement on what is considered an exotic animal.

The tiger in image 2 is advertised as a 3-year-old Bengal who has been with the family since he was a cub. A tiger, of any sub-species, is considered an adult at two years of age. According to Mazak [3], an adult male Bengal is roughly 8-10ft in length and weighs roughly 400-600lbs. While my point of view may differ from yours, the tiger in the picture definitely does not look like 400 pounds. My point is, the general online shopper would not know the difference between a 6-month and 3-year old tiger, and the difference could mean a drastic change in safety when handling an animal of this size. So do we limit the ownership of exotic species to size and safety? Or do we evaluate other areas of potential concern before making distinctions about private exotic ownership?

There is and may always be a debate on defining the behavior of animals. While some animals are more prone to domestication (i.e. dogs, cats, livestock), it appears that others are not. We can possibly attribute this to size, but what about each species’ instinctual behaviors? Instinctual behavior, also known as innate behavior, has been studied since the 1950’s and caused many fueled arguments. Konrad Lorenz, a famous ethologist well known for studying imprinting, wrote an elaborate paper on innate behavior. Simply put, he concluded innate behavior is spontaneous, reflexive, and spring-loaded [4]. This means that some behaviors do not occur predictably, and are reflexive to certain stimuli. Therefore, animals can react in multiple ways to the same stimuli, and the reaction can build (or wind on a spring), until the correct stimulus is presented and a behavior is emitted. This behavior can differ in intensity as indicated by the spring-loaded potential analogy. Relating this back to exotic pets, we can say that it is near impossible to predict the behavior of animals in homes. The effect of house-hold stimuli has not been studied on exotic species and there is little research on what makes an animal “snap” and become aggressive towards owners. Because animals can react differently to similar stimuli, what once made an animal affectionate could make an animal become dangerous. This un-predictable behavior causes the release of exotic pets into un-natural environments. This causes massive conservation concern as these “pets” predate on the native species that are un-adapted to the threat, become dangerous to nearby neighborhoods, and/or become nuisances to the surrounding area.  These contingencies focus on the human impact and safety of un-predictable behavior but the ethics of captivity should also be considered. Is it ethical to limit an animal’s instinctual behavior because we require it to have manners?

While I couldn’t find any primary research on the effects of the exotic animal trade on conservation, I also did not find any writing (primary or others) supporting exotic animal ownership. Two papers express their concern about the injuries resulting from exotic pets, both in the U.S. and Europe [5, 6]. Two others discuss the ethical concern associated with keeping exotic animals captive and exploiting them as products [1, 7]. These ideas are highlighted by an article from National Geographic  [8] discussing greed and human irresponsibility with these animals. A consensus among writers warns against the private ownership of such animals. As a society, it is our burden to decide which animals we are inclined to protect, whether it is the exotic pets in the trade or the native species that could be impacted by the irresponsible release of exotic pets. The effects of releasing exotic animals into unnatural environments are largely unknown, and it is unlikely someone predicted the Burmese python having such an enormous effect in the Everglade ecosystem. Therefore we should tread on the side of caution when determining when it is appropriate to obtain exotic animals and consider safety, ethical values, and conservational impacts.

 

References:

[1] Hess, L. 2011. Exotic Animals: Appropriately Owned Pets or Inappropriately Kept Problems? Journal of Aviane Medicine and Surgery.  Vol 25, Issue 1, pp 50-56.

[2] 2010. Big Cats Kept as Pets Across U.S., Despite Risk. National Geographic. URL: http://news.nationalgeographic.com/news/2002/08/0816_020816_EXPLcats_2.html

[3] Mazak, V. 1981. Panthera tigris. American Society of Mammalogists. No. 152, pp 1-8

[4] Lorenz, K. 1950. The comparative method in studying innate behavior patterns. Symposia of the Society for Experimental Biology 4 (Physiological Mechanisms in Animal Behavior). Pp 221-254.

[5] Lazarus, H.M., Price, R.S., Sorensen, J. 2001. Dangers of Large Exotic Pets from Foreign Lands. Journal of Trauma-Injury Infection & Critical Care. Vol 51, Issue 5, pp 1014-1015.

[6] Schaper, A., Desel, H., Ebbecke, M., De Haro, L., Deters, M., Hentschel, H., Hermanns-Clausen, M., Langer, C. 2009. Bites and stings by exotic pets in Europe: An 11 year analysis of 404 cases from Northeastern Germany and Southeastern France. Clinical Toxicology. Vol 47, No. 1, pp 39-43.

[7] Warchol, G. L. 2007. Transnational Illegal Wildlife Trade. Criminal Justice Studies: a Critical Journal of Crime, Law and Society. Vol 17, Issue 1, pp. 57-73.

[8] 2015. Big Cat Bans Enacted. Big Cat Rescue. URL: http://bigcatrescue.org/big-cat-bans-enacted/

The Better to Hear You With? Noise Mitigation in Captive Environments

By Victoria Garduno

African Cheetahs are facing one of the most dire extinction crises in the world today. Zoos and sanctuaries around the globe have been working tirelessly to try and protect them, first by navigating them through arguably one of the worst genetic bottlenecks we have seen to date, and now by carefully walking the tightrope that is captive cheetah breeding. Suffice to say, captive cheetahs are delicate creatures [1]. So you can imagine my surprise when, on a recent trip to Busch Gardens Tampa, I discovered that they had built a brand new roller coaster attraction…..which passed less than 100 yards from their cheetah enclosure.

Busch Gardens2

Portion of Busch Gardens Park Map, with cheetah enclosure in blue, and coaster passby in red.

 

The average roller coaster produces sound at anywhere from 40 to 90 decibels as it passes by an observer. This is about as loud as a jackhammer, and just shy of the point where hearing loss occurs in humans. In fact, the most noise is measured from the side of the cars, rather than the front or back[2], which means that the position from which the cheetahs, or any other animal which may be exposed, experiences the noise is actually the most extreme position, acoustically speaking. However, noise in captive situations is not limited to places which employ ride attractions. Many popular zoos have music and performance attractions, which, with the use of microphones, speakers, and amplifiers, are more than capable of producing enough sound to affect the captive environment. In some cases, the noise output from concerts or performances may even exceed the level produced by ride attractions.[3] Research has shown that zoo animals can be affected even by the crowds that visit them, showing increased vigilance and movements in response to escalating crowd noises.[4]

Chart showing relative decibel levels of common sounds.

Chart showing relative decibel levels of common sounds.

So then, what may be done in terms of noise mitigation? Continuing with my Busch Gardens case study, I secured an audience with a senior cheetah keeper at the park, who was able to shed some light on what had been done in this particular situation to reduce the effect of the coaster noise on the cheetahs. Surprisingly, most of the measures employed were behavioral. The most important part, she said, was done even before the cheetahs arrived in Tampa, when they were still at the sanctuary where they were received from, in Africa. Recordings of the cars going by on the track were made, and sent over to the sanctuary, where they were played for the cheetahs who were slated to take up residence at the park. This effectively habituated them to the type and level of the noise that they would experience, and decreased any negative effects which could be caused by sudden or unexpected exposure. Additionally, the recordings could be played softly at first, and then increased in volume to real-life levels once the cheetahs were comfortable. In other cases, habituation has been shown to reduce stress and startle responses in animals, both captive and wild, however, stress levels may remain elevated [5].

cheetah rest

In terms of sound design, clever engineering may be employed to reduce noise levels and reduce stress on captive animals. In the case of the roller coaster, there are many techniques which reduce noise, including filling the track with sand or vermiculite, and the addition of walls, buildings, or tunnels to absorb sound. These approaches may reduce the sound produced by ride attractions by as much as 20 decibels [6]. Additionally, animal enclosures also play a role in dampening sound. The shape of an enclosure has been shown to affect the type and level of sound that reaches the occupants, as well as the addition of trees, water features, rocks, and ‘ambient’ or ‘natural’ sounds. Exhibits which feature plexiglass fronts are also extremely effective against crowd noises, as those tend to be directionally oriented at the front area of an exhibit.[7]

sound2

In the case of the Busch Gardens cheetah coalition, this story does have a happy ending. Until recently, no cheetah participating in an animal ambassador program had ever had a successful litter. That changed in November of 2014, when one of Busch Gardens’ ambassador cheetahs, who had been previously housed at the park, produced a healthy litter of four cubs, two of which remain at the park. It would appear that the sound mitigation techniques, both behavioral and structural, were successful in reducing stress sufficiently for the cheetahs to feel comfortable enough to breed. If these methods are successful in cheetahs, it is probably safe to assume that they will also be successful in other, less fragile species. If we can implement these measures in zoos and sanctuaries across the globe, we may be able to improve the welfare of captive animals everywhere, and maybe even save ourselves a headache or two as well.

New arrivals!

New arrivals!

[1] O’Brien, S., M. Roelke, L. Marker, A. Newman, C. Winkler, D. Meltzer, L. Colly, J. Evermann, M. Bush, and D. Wildt. “Genetic Basis For Species Vulnerability In The Cheetah.” Science: 1428-434. Print.

[2] Menge, Christopher W. “Noise from Amusement Park Attractions: Sound Level Data and Abatement Strategies.” Noise Control Engineering Journal: 166. Print.

[3] “Sound Advice Note 10.” – Rock and Pop. Ed. David Adams. 1 Jan. 2007. Web. 26 Mar. 2015.

[4] “Zoo Visitor Effect on Mammals: Does Noise Matter?” Applied Animal Behavior Science 156 (2014): 78-84. Print.

[5] Knight, Richard L. “Responses of Wildlife to Noise.” Wildlife and Recreationists Coexistence through Management and Research. Washington, D.C.: Island, 1995. Print.

[6] Davis, Joshua I., Charles Birdsong, and Harold Cota. “Vibroacoustic Study of Circular Cylindrical Tubes in Roller Coaster Rails.” Noise Control Engineering Journal: 333. Print.

[7] AZA Ape TAG 2010. Chimpanzee (Pan troglodytes) Care Manual. Association of Zoos and Aquariums, Silver Spring, MD. 1.4 “Sound and Vibration”

 

Canned Hunting

By: Sabrina Berg

The lion must have thought, “As I look across the grassland, I see you standing there and I feel like I know you or have seen you before.  Hmmmm…  It seems to me that you used to feed me and take care of me when I was little and you were extremely gentle and caring so you cannot be that harmful. This means that I can get close and play with you without there being any danger to me.” Next thing you know the same human who has taken care of and nurtured them their whole lives is the one at the other end of the barrel. These poor lions and tigers are being betrayed by the ones they put all their trust in. When they have either been raised in a ranch facility or have been sold into another place that does captive hunting or canned hunting.

Canned hunting is a form of hunting where hunters will pay money to shoot captive animals on game ranches. For example, there was a video online of a lion being hunted that while held in a medium size cage enclosure. He was displaying stressful behavior, obvious from his repetitive movements of pacing back and forth. It became immediately apparent that the lion was trapped, making him an easy target for the hunter.  These animals, usually large cats, are typically taken away from their mother just hours after birth and are handled and bottle fed by humans.  Thus, the cubs become accustom to human interaction and they ignore their natural fears. Because of this, when it comes time to be “hunted” they no longer fear humans as they should, but instead, accept the potential hunters.  The young animals even begin to enjoy human company given that humans play, feed, and take care of them (2).

Canned hunting is unethical and not a fair fight for the lion because the shooters are actually picking out and paying for a specific domesticated lion that is friendly to humans.  Clearly this type of hunting is not for sport or sustenance, it is purely for the trophy. The hunter is not working at outwitting their prey and all he gains from the experience is a massive credit card payment and an animal carcass to show off to his buddies over a cheap bottle of scotch. The definition of hunting is the practice of pursuing any animal and trapping or killing it and canned hunting is not that.  The only similarity is the killing of the animal. Canned hunting could also pose a threat to the conservation of important top predator species such as lions, cheetahs and jaguars. If action is not taken against hunting practices like canned hunting, it may lead to the extinction of several endangered species.

A very important point I would like to bring to the table is how a lion’s behavior is influenced at an early age. Previously, I mentioned how cubs were taken away from their mothers in the first few weeks of life; this action could potentially contribute to the behavior of the animals because they are becoming accustomed to the lack of natural predators and don’t develop avoidance behaviors. Skills like this are important because they need them to survive in their native area.  Animals that are used for canned hunting are raised elsewhere, brought in, or purchased from individuals who are trafficking.  The animals can come from zoos, where they are unwanted or surplus, or possibly circuses who have no use for the animal (1).

Another issue that is misleading when it comes to canned hunting is the fact that game farms (ranches) mislead the public into thinking that the lions are being raised for conservation and reintroduction purposes. We see this a lot when vacationing in places like Mexico or South America. You see a photo op with a lion cub, or you pay to visit a farm to bottle feed baby cheetahs. Once you get to the farm, it is apparent that the cubs have no mother. The owners create a sob story about how the cubs were rejected or orphaned at an early stage (3).   They quote the visitor a fee which allows an individual to help bottle feed the cubs (3).  The owners make you believe that the money you are giving them will help the young cubs get a second chance to live free in the wild.  In reality, once the cubs get too big to be exploited for their “cute factor”, they are sold to hunting facilities. It is in these facilities that people pay to ‘hunt’ and kill large exotic carnivores.  So, in the future, if a farm or facility allows you be in contact with a big cat, you may want to question if it’s a legitimate facility.  Keeping lions captive in this way is not a means of conserving them, especially not the ones that are allowed to be handled by humans.  These lions are considered “human imprinted” and viewed as dangerous and will most likely be sold to a hunting facility (4).

Link to the video: http://www.theguardian.com/profile/patrickbarkham

  1. www.cannedlion.org. Campaign against canned hunting. February 25,2015.
  2. Barkham, Patrick. Canned hunting is a fast-growing business in South America, where thousands of lions are being bred on farms to be shot by wealthy foreign trophy-hunters. June 2013. February 25,2015.
  3. Bigcatrescue.org. Williams, Evan. Killing tamed wild animals in fenced areas for sport, petting cubs in Africa supports the canned hunting industry. November 26,2013. Website. February 25,2015.
  4. www.whitelionshomeland.org. Tucker, Linda. Canned Hunting. Assessed March 23,2015.

Keeping Our Friends Close, But Not Too Close…

Digger, a bear at Cheyenne Mountain Zoo, who was captured in Montana for being a nuisance

Digger, a bear at Cheyenne Mountain Zoo, who was captured in Montana for being a nuisance

Living in Colorado we often have to deal with wildlife encounters. Personally I have witnessed many wild animals simply roaming through my backyard as they look for food and go about their daily routines. Once my father walked in on a bear that was in our garage. And, although I love seeing animals as much as I can, we have to question if this is really a good thing. The case is different for every animal, but, as we encroach on their habitats, we need to be aware of what our presence is doing to the animals, and try to take some preventative measures to keep both us and them safe and healthy.

Bears have become a big problem for people because we are living closer and closer to their natural habitat. Living on a mountain I have seen my fair share of bears throughout my neighborhood, and, in seeing them so often, I have also witnessed how naughty they can be. Bears are notorious for exhibiting various kinds of “nuisance” behaviors that can get them into a lot of trouble, and it should be up to us to try and prevent this as much as possible so that they stay out of trouble and we stay safe. Bears that exhibit this behavior not only put us at risk, but also themselves, because when they are caught doing this, often times animal departments are instructed to “take care” of them, which is not good for bear populations if this behavior continues to escalate.

Bears are omnivores and therefore like to get their paws into just about anything so that they can get a meal [2]. And with us living increasingly closer to their habitats, they are discovering that they can use our resources for food as well. Since they are such smart creatures they can get their food from all kinds of sources—garbage, bird feeders, compost piles, pet food, barbecues, gardens, orchards, and anything else they can be intuitive enough to get into [1].   So taking all of this into consideration, if we wish to help bears remain wild and safe from being captured due to becoming a nuisance, it is up to us to try to be a little more bear-conscious of our homes and take some preventative measures.

The first step to this is to try and keep anything that would attract bears inside your garage or in the house. Keeping bird feeders high or on bear proof poles that they can’t reach and not overfilling them helps if you will be hanging them during bear season [1].   Keeping garbage and recycling bins inside is another important step, and don’t put them outside until right before they are supposed to be picked up [3]. I cannot tell you the amount of times I have seen trash cans turned over and the contents strewn through a yard because they were left out too long, or overnight and bears have gone through them. This can also be a very detrimental thing for bears. This is the number one attractant, and letting this become a problem means that these bears are often captured and sometimes killed because they have become a danger to humans because they frequent the area too much [1].

Many cities have employed the use of bear-proof trashcans in public areas that have had a generally positive effect. A study done in Florida reported a decrease in bear sightings and bear-human interactions once the trashcans were employed, as well as a positive attitude from local residents about the trash cans [4]. This kind of technology can be really useful when there is no way around having attractants out, and it is these kinds of solutions that need to be sought after when dealing with problems such as these. We need to work toward co-existing a little better with our natural world. And although humans don’t always care very much about protecting the animals of our world, if we can work toward better solutions that work for both parties, things have a much greater potential of getting better.

-Deanna Sinclair

Sources:

  1. http://www.env.gov.bc.ca/cos/info/bearaware/prevent_problems.html
  2. http://icwdm.org/handbook/carnivor/black_bears.asp
  3. http://www.bearsmart.com/live/overview/
  4. Barrett, et al., “Testing Bear Resistant Trash Cans in Residential Areas of Florida.” Southeastern Naturalist. 13(2014):26-39. Web.

Captive Breeding Programs: The Pros and Cons to Building an “Arc”

Captive Breeding Programs: The Pros and Cons to Building an “Arc”

Blog written by Emily Temple

Captive Breeding programs are departments within zoos, rescues, sanctuaries and so on in which animals are kept in enclosures and are bred to produce future generations of their species. There is great debate over whether these types of programs should be continued. This article aims to provide a basic approach to both the pros and cons to captive breeding programs both in the aspect of animal behavior and in animal conservation.

So let’s start with the positive aspects to these captive breeding programs. Zoos are some of the biggest funders of animal conservation projects and research, and where does that money come from. Most comes from the general public who pay to visit these zoos each year, multiple times a year, and those who feel compelled to donate. Some of the special draw that brings these people coming to the zoos is the possibility of seeing new cuddling, exotic, and special baby animals. For example the recent birth of a clouded leopard at Tampa’s Lowry Park Zoo is or will be a great draw for people to come and pay to get into the zoo to see the cute little cub. Now captive breeding programs are not only there to bring in a crowd, their main point is to help conserve animals that are endangered or threatened in the wild so that a species doesn’t become extinct. Extinction rates are going up and it is predicted that 20-50% of the world’s species will become extinct in the next couple decades [1]. So zoos can act as somewhat of an “arc” by holding the world’s species in captivity and saving their genetic material from total elimination. Some of these captive breeding programs also have goals for the reintroduction of these animals back into a natural or wild environment. These reintroductions can help in conservation efforts by keeping population numbers up and decreasing inbreeding and genetic drift.

Now, on the flip side, there are some cons to these captive breeding programs. A big problem that arises with captive breeding programs is the sheer numbers of animals in captivity. Most facilities don’t have the resources or the space to support a larger breeding program. Also captive breeding programs have a high cost to support and properly care for each animal so they consist of few animals that can’t sustain a proper breeding population [2]. Another major con to captive breeding programs comes in on the animal behavior side. Even though care takers try their very best to make captive enclosures as natural and stimulating as possible, they fall short of a wild/natural environment. So with this change in environment comes a change in these animals behavior. Some major changes in behavior are a decrease in predator avoidance, decrease in foraging abilities, increase in sleeping patterns, decrease in overall activity, and some problems in social behaviors. Some captive species even have problems in reproduction such as the endangered rhino populations, and that calls in to question the effectiveness of their captive breeding program. These changes in behavior are a major factor in whether these animals can be reintroduced into the wild and if it would benefit their population.

So overall, the question still exists. Are these captive breeding programs a good a bad thing? Isn’t it important to have some individuals of a species still existing somewhere rather than go extinct completely? Or is it better to try and just support the wild populations as they are and use other conservation techniques to keep the endangered species going even though that risks complete extinction. The debate is still up in the air and maybe should be evaluated on a species to species basis.

 

Citations:

Rahbek, Carsten. “Captive Breeding-a Useful Tool in the Preservation of Biodiversity?” – Springer. Kluwer Academic Publishers, 1 Aug. 1993. Web. 31 Mar. 2015. <http://link.springer.com/article/10.1007/BF00114044#>.

Snyder, N. F.R., Derrickson, S. R., Beissinger, S. R., Wiley, J. W., Smith, T. B., Toone, W. D. and Miller, B. (1996), Limitations of Captive Breeding in Endangered Species Recovery. Conservation Biology, 10: 338–348. doi: 10.1046/j.1523-1739.1996.10020338.x