Yesterday started off with a group trip to the Denver Zoo, which was a winter wonderland after the snow we had overnight.  I will definitely blog more about the zoo after returning home.  [Unfortunately I left my camera cable in New York and want to wait to write about it until I can do the day justice with photos.]

This morning officially kicked off the 7th annual carnivore conservation conference.  The theme of this year’s conference addresses the conservation challenge of climate change, and the implications that is has for the conservation of ALL carnivore species, not just those in the polar regions.

The day began with a representative from HawkQuest showcasing one of their captive-bred Harris hawk, which flew directly over my head.  HawkQuest is an organization that educates the public about carnivores, especially raptors.  ”Educating our youth, is paramount to this process,” said an employee of Defenders of Wildlife, whose name I failed to catch.

Next up was a representative from Wolf Park, a non-profit organization located in Indiana, to award the second annual Erich Klinghammer Award, named after  Dr. Erich Klinghammer, the behaviorist who founded Wolf Park in 1972.  This year’s recipient was Nina Fascione, the Vice President of Field Conservation for Defenders of Wildlife.

Eventually we got to our plenary session, “Ecological Consequences of Large Predator Removal: A Comparison of Five U.S. National Parks”, led by Robert Beschta and William Ripple, both of Oregon State University.  After reading about both of these men and their research in “Where the Wild Things Were” by William Stolzenburg on my way to Denver, it was a delight to hear them speak in person about their research on trophic cascades in Yellowstone National Park.  [More on this later!!]

However, it is now time for me to go back to my sessions….

I’m sorry to say, but I am not cool enough to run in a gorilla costume, like these folks:

For my friends and readers across the pond, you may want to participate in London’s Great Gorilla Run and run 7km in a gorilla suit to raise money and awareness for the 700 mountain gorillas remaining in the wild.

Some Fast Gorilla Facts from Great Gorillas:

There are 4 types and they all live in West and Central Africa:

1. Mountain Gorillas

One of the most endangered animals on earth. There will be as many Great Gorilla Runners in London in September 2008, as there are Mountain Gorillas – just 720!

2. Eastern Lowland Gorillas

There are an estimated 3,000 of these slightly less hairy gorillas, which doesn’t mean they are any less important. I guess this seems like quite a few compared to the Mountain gorillas but when you realise that there were around 17,000 only ten years ago you can understand just how threatened they are.

3. Western Lowland Gorillas.

These gorillas were thought to be relatively safe because they live in huge dense forests, which are pretty hard to get to. But that was before people started building roads through the forests and a nasty ebola virus killed thousands of them in just a few months. 60% of these gorillas have been wiped out in less than 30 years.

4. Cross-River gorillas.

Rarely seen, even more rarely photographed, these are some of the most elusive and threatened creatures on the planet – there may be as few as 250 left in the world.

African wild dogs and cheetahs, the smallest and most endangered of Africa’s large predators, have the greatest dietary overlap of all African carnivores, as well as the smallest number of prey species to choose from. Both species predominantly dine on Thomson’s gazelle and impala, two small species of ungulate. The risk of extinction increases when a species has fewer food options. Larger carnivores such as lions, spotted hyenas and leopards have more options in their prey, minimizing competition and giving them a more secure status.

Researchers from Nelson Mandela Metropolitan University (NMMU) in South Africa recently conducted a study on prey preferences and dietary overlap amongst Africa’s large predators. The species in the study were leopards, lions, spotted hyenas, cheetahs and African wild dogs. The conservation status of each species into was taken into account during data analysis, which served as a method to estimate the number of surviving individuals within each of the five carnivore species studied.

The researchers found that almost three-quarters of the actual diet for African wild dogs and cheetahs overlapped, the greatest amount of overlap between any of the other large carnivores. The overlap for the preferred diet of these two species was also over 70 percent.

When the scientists looked at the data in comparison to the conservation status of each species, they found that the smaller the dietary options available to a species, the more endangered that species was. Leopards, who have the broadest range of prey to choose from, are of the least conservation concern.

The evolution of Africa’s large predators is now negatively affecting those who evolved to become more specialized. African wild dogs and cheetahs, which have the fewest number of prey options, are also the most threatened, and also suffer from the greatest amount of dietary overlap.

The current theory is that competition with and predation by lions and spotted hyenas forces African wild dogs to exist at low densities. Long-term data shows that the wild dogs were most abundant in the Serengeti during the 1960s and 1970s, when lions and spotted hyenas were more scarce. Over the next two decades, as lion and hyena populations doubled, the African wild dog population declined up until local extinction. The recent findings in the study at NMMU suggest that food limitation may have been a factor in the extinction of the wild dogs in the Serengeti. The decline of the preferred prey species of the wild dogs placed them under greater pressure, and they ultimately went in extinct in that location.

African wild dogs also suffer from human persecution, habitat loss, disease and competition with lions and spotted hyenas. The larger predators interfere with the wild dog’s kills, in addition to lions actually killing the dogs themselves.

Cheetahs suffer from habitat loss, exploitation human interference, disease, predation as well as other predators stealing their food. Habitat loss is their greatest threat, because it reduces the availability of suitable prey species and thus reduces their success in hunting. Competition with other predators also threatens Cheetahs in the Serengeti, where lions kill cheetah cubs.

Cheetah cub mortality depends on the mother’s vigilance and anti-predator behavior. When the mother has to spend more time hunting because of fewer suitable prey options, she has less time to protect her cubs. The same holds true for African wild dogs. The more effort they have to put in to taking down prey, the fewer guard dogs they can leave behind to guard the pups.

Food limitation, and competition for resources between species can now be added to the list of threats for African wild dogs and chetahs, particularly in conservation areas that are free from habitat alteration and human persecution, but where management strategies have led to unnaturally high population densities of all predators found there, which reduces the availability of food.

Conflict with humans restricts large carnivores predominantly to conservation areas. But in clumping the carnivores together in one area, it increases the likelihood that they will have to compete for resources, such as prey, by creating artificially high population densities, and may eventually lead to further extinctions.

The successful management of conservation areas is crucial to ensuring that further extinctions do not take place.  One way to do this is to vary the prey species in the conservation area, and to make sure that the preferred prey species of the more threatened carnivores are available at all times.

By keeping an eye on things and actively engaging in the management of conservation areas, we can ensure that they only serve to booster endangered populations, rather than cause further damage.

Hayward, M., & Kerley, G. (2008). Prey preferences and dietary overlap amongst Africa’s large predators South African Journal of Wildlife Research, 38 (2), 93-108 DOI: 10.3957/0379-4369-38.2.93

The special brought up a lot of really important conservation issues facing blue whales, as well as other marine mammals.

The single biggest human act that decimated the blue whale population was whaling.  The blue whale population had once been estimated at more than 250,000 globally.  A ban on the commercial whaling oh blue whales was established in the 1966, but a century of whaling prior to the ban had already decimated the population by 90 percent.  Today it is estimated that there are now between 10,000 to 25,000 blue whales worldwide.

The International Whaling Commission (IWC) was set up under the rules of the International Convention for the Regulation of Whaling in 1946.  The main duty of the IWC is to review and revise the measures which govern the conduct of whaling around the world, largely guided by the advice from the scientific committee.  In 1982, the IWC decided that beginning with the 1986 season, a moratorium would be placed on commercial whaling of all whale stocks.  The moratorium allows whaling to be carried out by aboriginal groups if it occurs on a subsistence basis,  as is the case in parts of Canada, Russia, Indonesia and the Caribbean.  Yet Norway and Iceland still participate in commercial whaling, and Japan has been whaling since 1986  under commercial scientific research permits.

In Kingdom of the Blue Whale, geneticists Scott Baker and Steve Palumbi buy whale meat in order to see if any of it is from illegally killed blue whales.  This is a common practice for scientists, and has been used to test caviar to determine sturgeon species, or to test fish or meat in various markets to see if any of it comes from illegally hunted species.  Due to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (better known as CITES), which prohibits endangered species and their parts to be traded across international boundaries, the geneticists had to duplicate the DNA in their portable hotel-room genetics lab in order to bring it back to their own lab for testing.

DNA samples were submitted to GenBank, a genetic sequence database, to determine the species of whale meat from the Japanese market.  Their findings were frightening:  the meat came from a blue/fin whale hybrid.  Perhaps due to availability of suitable mates, blue whales are now mating with their cousins, fin whales (the second largest whale species).  Because they resemble fin whales from the top, the Icelandic whalers do not realize they are hybrids until after they are killed.  So far there have been 11 documented cases of blue/fin whale hybrids.  Hybridization threatens the genetic integrity of the species, which can lead to extinction of that species.

Ship strikes are yet another threat to blue whales.  In Kingdom of the Blue Whale, we learn that whereas one strike used to happen every few years, four were killed that season alone in California.  The scientists used forensics reminiscent of CSI to determine that the dead whale they found was a victim of a ship strike.  How did they know that ship strike was the cause of death, and didn’t occur postmortem?  Subdermal bruising indicates that the whale was alive when it was struck, something that would not have occurred if the whale had been hit after it was already dead.

Busier oceans means more hazards for blue whales, which feed in dangerous shipping lanes.  The increase in ship strike victims indicates that our bigger, faster, more powerful ships are now a greater danger to them.  Not only because of the possibility of ship strikes, but because of the increase in anthropogenic noise.  It is unknown how anthropogenic noise affects blue whales, but noisier oceans could mean that blue whales perhaps can’t hear each others’ calls.  Sonar has been implicated in mass-strandings of other marine mammal species, and examinations have revealed hemorrhages in the ears and brains of the deceased.

Despite the increased threats, it is not all gloom-and-doom.  Scientists are studying the life histories of blue whales to learn how to better protect them.  Further study of the Costa Rica Dome will also provide us with a better insight to the species.  In September 2007, the Center for Biological Diversity, a California conservation group, petitioned the federal government to reduce ship speeds off the U.S. West Coast.  The IWC is maintaining a database of ship strikes in order to detect trends over time.  Pressure from conservation groups has led to restrictions of underwater noise, and many oil and gas companies have now begun to limit their use of seismic air guns.  The Southern Ocean Sanctuary and the Indian Ocean Whale Sanctuary were established.  And then there’s you.

Be a scientist:

• Tag, track and identify individual blue whales like scientists Bruce Mate and John Calambokidis

• Follow the steps of scientists Steve Palumbi (Stanford University) and
  Scott Baker (University of Oregon), who used DNA data (“Barcoding”) to reveal the species identifications of kujira (whale meat) from foreign markets