Category Archive: Population Decline

Sep 15

Conservation Achievements in the Pantanal

Pantanal-telegraph.co.ukListed as an UNESCO World Heritage Area and one of the world’s largest tropical wetlands, the Pantanal covers 188,000 ha in western central Brazil.  Bordering Bolivia and Paraguay, this freshwater ecosystem, fed by the Cuiabá and Paraguay rivers, is home to a variety of species found nowhere else on Earth.  Modern pressures and an ever-growing human population continue to pose challenges for wildlife conservation and habitat preservation.  Research projects centered on such species as the lowland tapir, giant river otter, and jaguar work relentlessly to mitigate human-wildlife conflict and secure safe rangeland to ensure wildlife are protected and given the opportunity to thrive as they once did.

Since the late 1970’s, Panthera’s Drs. George Schaller and Howard Quigley have been working on an ongoingJaguar Archive.org comprehensive ecological field study on jaguar in the Pantanal.  One of the biggest threats to jaguars is conflict with beef farmers around the Pantanal region.  Farmers clearing land to plant crops or make room for cattle grazing has not only compromised jaguar habitat but also prey availability.  Using data collected from an almost 40 year study, jaguar conservationists have been able to gather insight on the lives of these magnificent creatures, i.e., where and when they travel and hunt, reproduction, genetics, etc.  Conservation efforts by Panthera working with national and local governments, as well as nongovernmental conservation groups have facilitated educational outreach programs helping locals understand why it is important to learn to live in peaceful coexistence with the jaguar and farmers better livestock husbandry practices to decrease the chance of a conflict with a jaguar and minimize environmental impact.  In addition, the establishment of the Jaguar Corridor Initiative will help reconnect jaguars via a genetic corridor from Mexico to Argentina.

Lowland TapirAlthough not as well known as the jaguar, the lowland tapir plays a significant role in maintaining the ecosystem of the Pantanal.  Looking a bit like a cross between a pig and a horse with a very flexible proboscis, tapirs are critical for seed dispersal, prey items for large predators like the jaguar, and shaping the landscape as they move through the area.  One of four existing species found on two separate continents, the lowland tapir is considered a vulnerable species by the IUCN.  Conflicts with humans via habitat destruction and hunting are currently the biggest threats to this unique megafauna.  Using radiotelemetry and camera traps, conservationists with the Lowland Tapir Conservation Initiative lead by Dr. Patricia Medici are gaining a better understanding on the social complexities, reproductive physiology, and distribution pattern of the lowland tapir.  These data will allow for conservation plans to be written to guarantee species survival.  Considered a keystone species, the tapir is considered fundamental for overall biome longevity.

Giant river otters remain endangered throughout their fragmented range.  Otter populations were decimated inGiant River Otter the 1950s and 1960s due to hunting for their pelts.  It was once thought total otter numbers were as low as under 100 individuals.  Conservation efforts have yielded in a significant increase in giant river otters over the last 30 years; however, habitat degradation, conflict with fishermen, and depleting food sources remain an ever-present threat.  Conservation projects focusing on reproduction, environmental requirements (den sites), and diet have helped otter biologists develop long-term management initiatives.


The Pantanal is home to over 80 mammalian, 650 bird, 50 reptilian, and 400 fish species, some of which are unique to this area.  Through persistence and passion, conservation groups are gaining ground to secure precious habitat and help in the overall survival of some amazing creatures. As it is seen all around the world, human-wildlife conflict appears to be the underlying cause of habitat degradation and loss of populations.  Gathering data to better understand how wildlife utilizes, contributes, and travel through their habitat gives conservationists a foundation on which to build long-lasting conservations plans.  What we learn today can be applied to not only help future generations of wildlife but also humans within the breathtaking Pantanal.

 

For more information on the Lowland Tapir Conservation Initiative and Dr. Patricia Medici please check out the following links:

http://www.waza.org/en/site/conservation/waza-conservation-projects/lowland-tapir-conservation-initiative

http://news.mongabay.com/2011/0911-hance_medici_interview.html?homepg

 

You can find more information about Panthera’s work with the jaguar at the following link:

http://www.panthera.org/species/jaguar

Aug 22

Emerging Zoonotic Diseases in Wildlife

Outbreaks of infectious disease make headlines around the globe almost daily.  Viruses, bacteria, fungi, protozoa, and parasites have the potential to affect both humans and animals alike.  A variety of infectious diseases can also be categorized as being zoonotic meaning they can be transmitted to other species.  As reported by the Center for Disease Control (CDC) and the World Health Organization (WHO), at least 2.2 million human deaths annually are the direct result of zoonotic pathogens.  As for domestic animals and wildlife, there is not an accurate number due to the under reporting of sickness in developing nations.  For our focus, we will discuss those zoonotic diseases that affect wildlife, be it from domestic animal or human contact in captive and wild populations.

A close relative of measles, canine distemper is a paramyxovirus known to cause sickness in wild and domestic canids, wild felids, viverrids (genets, binturongs, civets), members of the weasel family, red panda, hyenas, procyonids (raccoons, coatis, kinkajous), and fin-footed marine mammals (seals, sea lions, walrus).  Highly infectious, canine distemper continues to be a major threat to wildlife conservation.  Spread commonly by the domestic dog, canine distemper contributed to the near extinction of the black-footed ferret in the United States, is a frequent cause of death in African wild dogs and lions, and may have been a significant factor in the total eradication of the thylacine or Tasmanian tiger.  In addition, because this disease is so wide-spread it is often mistaken for others with similar symptoms like rabies.  Although an effective vaccine was developed in 1950, the virus remains prevalent worldwide due to limited use or lack of vaccination programs.

Herpes viruses are members of a very large family of latent viruses that reoccur throughout the lifespan of an infected individual.  Although there are species-specific herpes viruses, there are also those that cross-species and in doing so become deadly.  Elephant endotheliotropic herpesvirus has been identified in both wild and captive Asian and African elephants.  It is hypothesized that while each elephant species has specific strains of the virus they live within an animal of that species with no serious health effects, it is when a particular strain is transmitted to the other species that it almost always results in death.   Similarly, a strain of herpes virus known to cause sickness in zebras was recently identified as the cause of death in polar bears at a zoo in Germany.  However, in the wild these species would never cross paths, so it is possible that these types of infections are strictly held to captive wildlife.

Anthrax is a lethal bacterium known to cause sickness in humans and animals.  Found on every continent, including Antarctica, Anthrax spores are very hardy and can live for years under extremely harsh environmental conditions.  Most commonly documented infections occur in areas where domestic livestock and wild herbivores share grazing land via fecal/oral route.  While vaccinations for Anthrax do exist, and successful treatment with antibiotic therapy has been proven, limited use allows for this disease to persist.  Like with distemper, Anthrax poses a great threat to wildlife, endangered species of particular concern.

Chytrid is a species of fungus that is decimating the world’s amphibian populations.  Thought to have originated from the release of infected African clawed frogs (who are themselves resistant) into non-native habitats, chytrid is solely responsible for the almost 90% decline in global amphibian numbers.  Furthermore, humans have also been identified as carriers of Chytrid on field equipment and clothing.  Interestingly, a recent report has shown that Chytrid has been transferred to different habitats on the feet of migratory birds, specifically Canada geese.

Zoonotic diseases are global health risks for all species.  Most importantly, for my line of work, they pose a great threat to wildlife conservation.  Whether you are a field researcher or simply live near wildlife habitat,everyone has a part to play in the reduction of transmission of these pathogens.  Vaccination programs for domestic animals are a huge contributing factor in disease prevention.  Making sure to clean equipment and clothing when traveling into different wild areas can eliminate the introduction of non-native and unwanted viruses, bacteria, fungi, parasites, etc. into native populations. In addition, good communication via reporting any suspected sickness in encountered wildlife to the proper authorities can be instrumental to prevent possible epidemics from occurring.

Apr 30

Animal Extinctions: What Can We Learn From Past Mistakes

Across the globe animal species are going extinct.  From such contributing factors such as disease, persecution, poaching, displacement, and habitat destruction, we are losing some of our most amazing creatures at an alarming rate.  Unfortunately, species extinctions are nothing new.  But can we learn from past mistakes to ensure more magnificent animals do not do the way of the dodo?

One of the most iconic species to have become extinct in the 20th Century was the thylacine or Tasmanian tiger.  The last known thylacine was observed in captivity at the Hobart Zoo in 1936.  Although the thylacine was a large nocturnal, carnivorous marsupial, it was no threat to humans.  Like the Tasmanian devil, the main diet of the thylacine consisted of wallabies and kangaroos.  However, due to human encroachment, the thylacine became tempted to steal chickens and sheep which ultimately was its death sentence.   A bounty was placed on the thylacine encouraging the uncontrolled killing of all.  By the time it was realized that thylacine numbers were decreasing too rapidly to sustain a population it was too late.

In 1966, Dr. Jay Savage first observed the Golden Toad of Costa Rica.  Less than 20 years after its discovery, it was estimated that only 10 toads were left in the wild.  By 1989, the Golden Toad was extinct.  Globally, amphibian populations are being decimated by chytrid fungus infections.  Chytrid is a nondiscriminatory killer that causes a thickening of the skin of infected individuals.  Because amphibian respiration is unique in that it occurs through the skin, a thickening of the dermis causes death via suffocation.  Although no Golden Toads were ever found with chytrid, it is assumed that the fungus was probably the most significant extinction factor for this species.

The last Vietnamese Javan Rhino was shot by poachers in 2010.  Once found in a vast home range covering Vietnam, Cambodia, Laos, Thailand, and Malaysia, the Vietnamese Rhino was hunted to extinction by the demand for its horn.  Although no real medicinal properties have ever been documented, rhino horn is highly sought after in Ancient Chinese Medicine as a cure all.  All species of rhino are under threat as the black market value of rhino horn has hit an all time high of $30,000 US for a single horn.

 

 

 

 

This year, the International Union for Conservation of Nature and Natural Resources (IUCN) will sadly add more names to the extinct column on their Red List of Threatened Species.  Identifying the threats to wildlife populations is no longer the problem; researchers understand the factors contributing to animal extinction.  The bigger issue is how do we stop already declining populations and prevent future collapses from occurring.  Can we make a conscious effort to learn from our mistakes to help other species survive?  Or will some of the most magnificent creatures ever to walk the earth be forced to share space on the extinction list with the dodo?

Feb 20

The Year of the Dragon

The dragon is both revered and feared in many cultures around the world.  This year the Chinese will celebrate the upcoming new year as the Year of the Dragon.  A symbol of strength and royalty, you can find interpretations of these mythical beasts adorning clothing, wall tapestries, statues, and even etched into flesh.  But what do we know about our last remaining dragon, the Komodo dragon, which still walks the earth?  What is being done to conserve this magnificent creature and its habitat to ensure that it too remains immortalized?

Weighing in at up to 100 kg (220 lbs) and measuring 3 m (9 ft) from nose to tail, the Komodo dragon is considered the world’s largest lizard.  Although a stable population of 3,000-5,000 individuals can be found on the Indonesian Islands of Komodo, Gila Motang, Rinca, and Flores, overall the dragon is considered endangered.  The Komodo dragon is the apex predator in its ecosystem feeding on everything from carrion, deer, feral pigs, smaller dragons, and buffalo.  Ferocious predators, in one sitting, the Komodo can consume 80% of its body weight!  Even more fascinating is that parthenogenesis has been documented in this species.  Several zoos around the world have observed single females laying viable eggs that she fertilizes herself, sans male partner.  A side note is that in every case the eggs hatched yielding only male offspring.  This incredible reproductive process allows for females to enter an isolated ecosystem and produce offspring that can become founding members of a new population.  However, caution is warranted as scientists do not yet know the detrimental effects this may have on genetic diversity.

 

You would think that by its size and fierceness, the Komodo dragon would be a formidable opponent for all challengers, but this is not the case.  Human encroachment and poaching threatens the survival of the Komodo on every island that it inhabits.  Indirectly, natural disasters such as volcanic activity, earthquakes and fires, loss of prey due to poaching, and negative effects from unsustainable tourism have all contributed to a decrease in dragon numbers.  In addition, it has currently been reported that out of the total population there may only be ~300 reproducing females.

As with any conservation effort, the hardest part is trying to identify the most effective way to begin.  From a conservationist point of view, the population needs to continually be monitored so that any changes are immediately known.  It is also important to characterize the genetics within the current population to detect genetic bottlenecks.  Environmental education programs are needed to help local people living in Komodo habitat understand the importance of the dragon and why they are beneficial in the ecosystem.  In addition, increased legislature is needed to protect the Komodo dragon and presence of wardens required to help prevent poaching of dragons and their prey.  However, regardless of conservation initiatives, none of these things can be accomplished without public support.  Monetary donations are essential to fund conservation projects.  Additionally, awareness, education, and support to conserve Komodo dragons and their habitat via volunteering, word of mouth, or community involvement are imperative to get others to care about the plight of such an amazing creature.  Let us all work together to make every year the Year of the Dragon.

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