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October 31, 2005

From Vampiric Spiders To Owl Engineering

OWL2.jpgIn honor of my favorite holiday - Halloween - I thought I'd post about some spooky creature behaviors of interest.

Blood-Sucking Spiders

Jumping spiders are creepy enough, but how researchers have found that there is a spider in Eastern Africa that lives on human blood. However, kind of like the Vampire Lestat feeding on rats because it's safer than dealing with stake-in-the-heart humans, the blood-sucking spiders have found that snacking on mosquitoes is a safer way to get their fix than getting smacked-down by a human...

They say the spider, which hunts blood-sucking female mosquitoes, is the only animal known to select its prey based on what the prey has eaten.

...

Spiders don't have the skin-piercing mouth parts needed to feed directly on human blood, but the mosquito-munching jumping spider appears to have got around this. The strategy has other advantages as well, Nelson points out.

"Blood-feeding is a dangerous activity," she said. "Animals that are bitten have a swatting response, and often the insect is killed."

By eating mosquitoes, the spider avoids the risk of being squashed by an unwilling blood donor.

More at: African Spider Craves Human Blood

Hooting Fiends Luring Dung Beetles To Their Deaths

Tool usage in animals is something I'm fascinated with. It seems to be considered advanced behavior and it's certainly intelligent on some level, but I would really like to know how biologists define tool usage. My working definition is using a foreign object for something other than its intended use - for example, using a rock to break open a shell or a reed to suck termites from a mound or a dolphin protects its nose by wearing a sea sponge.

Is the weaving of a web by a spider tool usage, or the hidden door behind which the trapdoor spider hides? Now owls have joined the tooling animals with their interesting bug-luring dung usage that is almost like a primitive kind of farming.

Burrowing owls' habit of bringing mammal dung to their burrows is an example of tool use, researchers say. The dung attracts beetles, an important part of owl diets, the scientists have found.

More at: Owls use tools: Dung is lure for beetles

Glow-In-The-Dark Pumpkins

I first heard about this extraordinary toxic cleanup method on the Earthwatch Radio podcast earlier in the month. Sortof like the poisonous but beautiful oleander flowers that help clean up the carbon dioxide and toxic fumes along the freeways, scientists are increasingly turning to horticultural methods to handle managemen of toxins. Most recently, there's been some research on using squashes to extract nasty toxins from the soil.

Some toxic chemicals that were taken out of production during the 1970s are extremely persistent and still linger in the environment. In North America, some places are still tainted by the pesticide DDT and industrial chemicals known as PCBs. Scientists are testing plants to see if they can clean up these places, and they say pumpkins and zucchini do the job pretty well.

More at: A Helpful But Hazardous Harvest

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Bats In The Belfry & Lions In The Tower

You've heard of bats in the belfry, but what about heard of lions in the Tower? The Tower of London, that is.

Evidently, the Tower, which is infamous for housing Elizabeth I during her sister Mary's reign and for its bloody executions, once served as the longest continually running zoo. For six centuries (approx. 1204-1835), the Royal Menagerie housed a number of exotic animals, many of which were given to the royal family by foreign nations.

When the menagerie was regularly open to the public in the 1800s, visitors would have their admission fees waived if they brought their pet cat or dog to feed to the lions...

Two lion skulls unearthed at the Tower of London have been dated to Medieval times, shedding light on the lost institution of the "Royal Menagerie".

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The best preserved lion skull was radiocarbon dated to between AD 1280 and 1385, making it the earliest Medieval big cat known in Britain. The period when it lived covers the reigns of Edward I, II and III

More at: BBC NEWS: Big cats prowled London's tower

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October 30, 2005

Bugs Against Drugs

bugs.jpgMost people associate the ability to be trained or "learn tricks" with more evolved or intelligent creatures like dolphins or dogs, but sometimes one needs only to go back to the basics.

Police dogs can help find anything from drugs to explosives to people. It takes very extensive of training for both the dog and its handler, followed by constant and continued exercises and maintenance.

The costs of efficient canine training courses can be astronomical... Unfortunately purchase prices for quality, commercially trained narcotic detector dogs are presently in the vicinity of $5,000 to $10,000. Well beyond the budgets of most law enforcement agencies

More At: Narcotic Detector Dog-Team Project

Dogs certainly have keen senses, but they are also difficult to manage - possibly because they are more "evolved" - they need constant attention and are easily distracted. Now scientists are turning to some considerably simpler creatures that also have the nose for the job... bugs!

According to researchers, wasps may be ideal for the job of sniffing out drugs and bombs. They can be bred in large quantities and need only 30 minutes of training. The tricky part is harnessing this ability.

Sneaky drug smugglers and terrorists may soon meet their match: a handheld chemical detector powered by trained wasps.

Dubbed the Wasp Hound, the prototype tool houses five parasitic wasps that react to the smells of explosives, illegal drugs, and plant diseases. In theory, the insects' movements set off an alarm to alert authorities.

...

Later research revealed that the wasps' olfactory system was directly linked to their taste receptors and that the insects learn to associate certain smells with food or with corn borers.

More at: Drug-Sniffing Wasps May Sting Crooks

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October 29, 2005

Fishtory: Overfishing Through the Ages

lobster.jpgLobster hasn't always been a rare or special treat, offered by the best restaurants in the world. At one time, it was considered "poverty food" - Native Americans fertilized crops with them, fishermen baited hooks with them, and servants boiled them for their supper. During the revolution, Americans insulted the red-coats by calling them the icky bottom-dweller "lobsterback".

Long ago, lobsters...were harvested from tidal pools and served to children, to prisoners, and to indentured servants, who exchanged their passage to America for seven years of service to their sponsors. In Massachusetts, some of the servants finally rebelled. They had it put into their contracts that they would not be forced to eat lobster more than three times a week.

More At: Lobstering History

Cruel & Unusual?
It was so commonly used as a food for servants and prisoners that Massachusetts passed a lobster law forbidding its use more than twice a week!

It didn't take long for the populations of lobster and other fish to suffer from overfishing. Over time, different fish have been found to meet the food demands, and the price or worth of a lobster/oyster/etc has changed. Now scientists are looking back through time to determine which species have thrived over the years and which ones have been driven to the brink of extinction by overfishing. As part of the survey, the researchers are examining old restaurant menus, which they believe will reflect how abundant or scarce certain fish populations were at the time.

Fisheries experts are using old restaurant menus to piece together how the world's seafood stocks have declined over the past century and a half. Prices dating back to the 1850s highlight the growing scarcity of foods such as lobster, swordfish and oysters.

More At: Old Menus Reveal Collapse Of Fish Stocks

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October 25, 2005

Fast Fishes: Great White Shark Speed Record

shark.jpgVery little is known about great white shark migration, but lately several have been tagged and tracked as they move through the oceans. Researchers found that great whites do some serious migrating - more miles a year than your average car lease!

A female great white shark has completed the first documented round-trip ocean crossing by a shark, swimming farther than any other known shark, according to a new study.

Nicole, as the shark is being called, traveled from Africa to Australia and back—a total of 12,400 miles (more than 20,000 kilometers)—in nine months. The feat also set a second record: fastest return migration of any known marine animal.

More at: Great White Breaks Distance, Speed Records for Sharks

Actively tracking great whites is a relatively new technology. When the Monterey Bay Aquarium re-released the young great white from captivity as part of their White Shark Research Project, they rigged her with a satellite tag that tracked her movements in the wild. These tags are temporary, collecting data on position, water temperature, and ocean depth. Then, on a pre-determined date, the tag disconnects from the shark and is picked up by researchers to analyze without having to recapture the animal. You can even see a map of the shark's progress on the Monterey Bay Aquarium website and they have also tagged six other young great whites in the wild.

The Pelagic Shark Research Foundation has also been tagging and counting great whites and other pelagic sharks in the Monterey Bay as part of several studies. They've put some of their research on their website including depth information, swimming patterns and lots of pictures. They use both passive and active tracking - but satelite tracking is very expensive.

Interested in following the movements of marine animals? WhaleNet's Satellite Tagging Observation Program (STOP) posts data from a variety of tagging and tracking projects currently underway, from sea turtles to elephant seals to whales. You can get lots of raw and analyzed data on the website. The previous tagging events archive is especially interesting.

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October 24, 2005

Caught On Camera: Stealth Logging In The Rainforest

macaw.jpgUltra-high resolution satellite photos have recently shown that selective logging is taking place in the Amazon rainforests and key old-growth trees are disappearing in record numbers. Until now, the damaage caused by this kind of logging was hidden beneath the forest canopy, but now new technology is shedding some light on the problem, but the news isn't good.

Damage to the Amazon rain forest has been underestimated by half, according to new high-resolution satellite images, which have revealed long-hidden logging activities.

Scientists say a new satellite imaging system that can penetrate the rain forest canopy shows that "selective logging," the singling out and cutting of commercially prized trees, poses a far bigger threat to the Earth's largest tropical forest than previously thought.

More at: Amazon Logging Twice as Heavy as Thought, Images Show

Logging companies have defended selective logging as a low-impact method compared to clear-cutting, especially considering soil erosion concerns. Friends of the rainforests claim the damage done is still too great. It's not just that old-growth trees are targeted, but that the roads and clearing done to reach each tree causes a lot of additional damage. Having seen some terrible clear-cutting in the Pacific Northwest, I can see why it's a taboo word for the rainforests, but I can also see how clearing a small section of forest completely might have less of an impact on the whole. It would need only one road, one sectioned off area, leaving the majority of the forest intact and pristine. Building roads and pulling individual trees would weaken the entire forest, making it more vulnerable to disease and invasive species. Ideally, the logging would stop altogether, but that doesn't seem likely at the moment...

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October 19, 2005

Living With Predators - Tigers

tiger.jpgAs Asia struggles with overpopulation and hunger, people move farther and farther into the wilderness to live and work. Farmers, hunters, and loggers increasingly come in contact with wildlife. This results in more and more conflicts between tigers and humans.

Villages have sprung up in and around national parks and wildlife preserves where tigers live. The villagers brave the tiger reserves at night to illegally collect honey and wood in order to make a living. Unlike most wild tigers, the swamp tigers of the Sundarbans between India and Bangladesh are famous for being man-eaters.

What makes a tiger a man-eater? Most tigers who attack and eat humans are sick or have been injured in some way. However, once they've aqquired the taste - and perhaps realized how easy the hunting can be - they are likely to continue to hunt humans.

Risking Life & Limb To Feed The Family

Tigers live in areas where people are often the most impoverished. Sometimes locals will hunt wildlife like the tiger just to feed the family. There have been several high profile cases lately of tigers killed to be eaten out of hunger and because consuming the flesh of animals such as tigers have long been thought to help improve health and vigor.

In the swamps of the Sundarbans, these man-eating tigers exhibit all sorts of traits not common in your average wild tiger. They're known for sneaking up on the men while they're foraging - often by swimming up to boats and climbing aboard and dragging some unsuspecting villager away. They've have taken to wearing masks on the backs of their heads in order to confuse the tigers and keep them from ambushing them from behind.

Villager Vengeance

Unfortunately, when someone is taken by a tiger, their family and village often retaliates by hunting down the tiger and killing it. This can lead to not only destroying the man-eater, but also other tigers along the way.

Authorities are trying to educate villagers about the tiger situation and how having tigers benefits the local economies by providing tourist income as well as jobs. Parks and reserves are also teaching the locals how to avoid becoming a meal and attempting to condition tigers to avoid humans - for example, by setting up human dummies that cause electric shocks.

Organized Poaching For Profit

Tiger heads, skins and claws are sometimes collected as wildlife trophies, but that's not the only threat facing the tiger today. Tiger parts are considered to have all sorts of medicinal uses - some of which are legit and some of which are myth. The bones of a tiger can be used in all sorts of Chinese medicine, and certain sexual organs are thought to be aphrodisiacs and cures for impotence. Tiger skins are often used in Chinese ceremonial costumes.

Silly as these uses may seem to us, there are a lot of people in the world who really believe in these remedies, and so where there's a demand, there will be a supply - regardless of the protected status of the tiger.

Since Environmental Investigation Agency's visit last year, there has been a massive increase in the availability of tiger and leopard skins in Lhasa, TAR. In the 46 shops surveyed, 54 leopard skin chubas and 24 tiger skin chubas were openly displayed, 7 whole fresh leopard skins were presented for sale and, within the space of 24 hours, investigators were offered three whole, fresh tiger skins.

More at: Tigers under threat from skin trade

Unfortunately, the punishments for tiger poaching are not particularly stringent. As tiger sales become increasingly lucrative, the poor villagers may sometimes come to the conclusion that the opportunity to bag a tiger outweighs any potential punishment or environmental concerns - especially when the proceeds might feed the family, or even the village - for quite some time.

Poachers come from all over the world to hunt the tiger. Much like drug rings, they can be ruthless in their black-market activities. Organized poaching is perhaps the most significant threat to the tigers today, even more than habitat loss. These mafiaesque gangs can systematically wipe out whole tiger preserves, as well as act as a middleman for the independent village poacher. Due to bribery and intimidation, the locals often do not report these poaching gangs to authorities. In one recent case in India, an entire park of tigers up and disappeared over the course of one season.

The raging scandal over the missing tigers of Sariska has shocked the country. Where have the tigers gone?

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According to the official census, in 2003 there were 25 to 28 tigersand in the 2004 census, 18 tigers were reported. In 2005, all were missing. Nobody knows what happened to the tigers. Perhaps those who knew just kept quiet.

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Sariska lies between two major cities — New Delhi and Jaipur — with two State highways running through it. Nearly 50 villages lie within its limits and around 40,000 people live in those hamlets.

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"An international racket behind this. The marble quarry lobby, backed by political tycoons, also does not want tigers there. The forest department is ill-equipped. Then how can the tigers survive?" asks E. Kunhikrishnan, zoologist and environmental activist.

After the Sariska story broke out, the government machinery suddenly recognised the existence of the poacher route that extends from New Delhi to Nepal, Lhasa (Tibet) and China.

"First it must be recognised by everyone that there is no substitute for good protection. An organised, well-connected mafia is involved in poaching. Punishment must be severe and swift," points out Dattatri.

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"Tigers aren't safe anywhere in India. Three years ago, a gang of tiger poachers from a village near Katni, Madhya Pradesh were caught red-handed at Nagarahole, the premier game sanctuary in Karnataka. This came to light only because a tourist happened to film a tiger limping with a jaw trap attached to its foot," says Dattatri.

...

Poisoning the kill, trapping and shooting are the most common methods used to kill the big cats.

More at: The Hindu: Spot the tiger


Living With Predators is a series of posts on this blog, covering a myriad of situations in which humans and dangerous animals live together, and how they cope. You can read more in this series, so far we've got:

Living With Predators - Crocs
Living With Predators - Hippos

You can also read more about the The Man-Eating Tigers of Sundarbans on my earlier post.

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October 18, 2005

Sudden Oak Death & The Invasion of the Mud Snails

It seems like every time I go to a state or national park lately, I encounter some sort of warning about some invasive species threatening the area - directly or as vectors. Sometimes it's a disease that kills off ancient trees, other times its an aggressively growing garden plant that's choking up waterways, and still other times, it's a non-native animal with no natural predators multiplying like crazy - like the Burmese Pythons in Florida we talked about last week.

Sudden Death

dv2.jpgLast time I went for a hike at Elkhorn Slough along the Monterey Bay, I had to step through a shoe chemical treatment to help prevent the spread of Sudden Oak Death. There was also a "least wanted" list posted which identifies Monterey Bay's worst invasive species.

According to the latest California Oak Mortality Task Force Report, the approximately 50,000 visitors annually are asked repeatedly to clean their shoes before walking on the trails of the slough in order to to prevent the introduction and spread of Sudden Oak Death - a devastating mould infection.

Invasion of the Mud Snails

fisherman.jpgWhen we arrived at our campground in the High Sierra this past weekend, we were ready for bear warnings, some moderately severe end-of-autumn storms and some kamikaze fishermen. What we got was a warning to help stop the spread of one of the many invasive species threatening the Sierras - the New Zealand Mud Snail - an invasive little mollusk that hides out in fishing gear.

The New Zealand Mud Snail is one of the leading invasive species threatening some of the endangered native fish all along the Pacific Northwest rivers. Unfortunately, the snail can reproduce asexually and shows a resistance to the common treatments used to combat other pests. However, once established, the little snails disrupt the food chain by eating the algae. Soon all the little insect larva that eats the algae is starving, and guess what eats the larva - baby salmon and baby trout. One of the primary ways in which these little mud snails spread is by hiding out in fishing gear like waders.

There was also a sign to help prevent the spread of the Asian Longhorned Beetle as well. It's become well-established on the East Coast and has caused a lot of damage. At first, they've only shown up in Chicago and New York, where they've decimated maple, horsechestnut, elm, willow, birch, poplar, and ash trees. Then they spread to nearby New Jersey. Now they've come to California...

Invasive Species Force Native Species Out

Non-native species enter the environment in all sorts of ways:

By hiding out in the ballast water of shipping vessels
By releasing an exotic snake into a nearby swamp
By dumping a water garden into a stream
By visiting a foreign environment and then visiting a local one

The one thing that's common about invasive species is that once they've become established, they influence the food chain and how all plants and animals work together in an environment. Non-native species often have few or no predators, allowing them to thrive while stealing the very resources needed by native species.

All native species are at risk when invasive species are introduced, whether by accident or on purpose in some cases. But it's the species that are already endangered that are of the greatest concern.

Almost half of the species on the U.S. endangered species list are threatened wholly or partly by introduced species.

More At: Huge, Freed Pet Pythons Invade Florida Everglades

That said, it should also be noted that invasive species has a greater potential of rendering a healthy population of a native species endangered, as well.

Combating The Invasion

flag.jpgIn 2004, the Forest Service Chief Dale Bosworth gave a speech highlighting the Four Threats to the Nation's Forests and Grasslands - fires, invasive species, development, and unmanaged outdoor recreation. The Four Threats Projects were launched to help focus Forest Service policies to address the concerns, and all of these warning signs and public education programs are part of this fight against invasive species.

The U.S. spends $13 billion per year to prevent and contain the spread of invasives. For all invasives combined, the price tag is $138 billion per year in total economic damages and associated control costs.

More at: US Forest Service: Four Threats

Despite being a huge money sink, from a legislative perspective, the future isn't bright. Various bills in Congress, aimed at combating invasive species, are languishing. The Endangered Species Act itself is under threat, including some proposed invasive species changes that could cripple the act.

Legislation aimed at preventing foreign fish, clams and marine creatures from entering ... in oceangoing ships is languishing in Congress while the shipping industry pushes a less restrictive bill.

More at: Bill aimed at invasive species languishes

More About Invasive Species

If you're interesting in more about how invasive species are affecting our environment, you may want to check out some of the following resources. Dr. Jennifer Forman Orth runs an Invasive Species weblog worth checking out and there's also InvasiveSpecies.Org, a joint organization including the US Forest Service. Lastly, the National Wildlife Federation has a couple good examples of invasive species and their biological and fiscal impacts.

I also have written about specific invasive species here before, for example:

Gator Gluttony: A Python's Fatal Mistake
Endangered Species Act Could Become Extinct

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October 17, 2005

Autumn In The High Sierra

Living in Santa Cruz, Shane and I are always lamenting the lack of seasonal change on the California Coast. In order to get our autumn color fix in, we spent the weekend in the High Sierra, around Mono Lake and Yosemite. Boy, were we in for a treat!

Although the weather was cool (it snowed on us a couple of times), the weather was mostly very clear and sunny. Photography was a bit of a challenge due to the very heavy winds which rattled not just the brightly colored leaves, but also made even the largest of trees sway.

We drove up through Yosemite, over Tioga Pass and down into Lee Vining Canyon, where we camped along the aspen-lined creek with Mono Lake just 5 minutes away. We also took a day trip down to the June Lake loop, which follows a nice canyon filled with aspen groves and a couple of meandering creeks.

Here are some of the photos I took over the weekend. Click on any picture to see a larger version. Hope you enjoy!


June Lake In Autumn
Taken on Oct 15, 2005, with a Canon 20D
Muliple Exposure Panorama (ISO 100)


Lee Vining Creek
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 1/13 at f/10.0 (ISO 100)


Aspen Grove
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 1/200 at f/11.0 (ISO 200)


Aspen Grove
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 1/30 at f/9.0 (ISO 100)


Fall Color - Lee Vining Canyon
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 1/100 at f/8.0 (ISO 100)


Autumn Creek View - June Lake Loop
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 1/13 at f/20.0 (ISO 100)


Autumn Colors - Lee Vining Canyon
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 1/60 at f/6.3 (ISO 100)


Aspens In Autumn - Lee Vining Creek
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 1/125 at f/9.0 (ISO 100)


Lee Vining Creek
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 0.5 at f/20.0 (ISO 100)


Autumn Reflections - Lee Vining Creek
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 1/13 at f/4.5 (ISO 100)


Autumn Color - June Lake Loop
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 1/160 at f/8.0 (ISO 100)


Autumn Reflections - Lee Vining Creek
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 0.3 at f/10.0 (ISO 100)


The Birdhouse - Poole Power Plant Road
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 1/200 at f/3.5 (ISO 100)


Autumn Aspen Detail
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 1/100 at f/8.0 (ISO 100)


Lee Vining Creek
Taken on Oct 15, 2005, with a Canon 20D
Exposure: 0.6 at f/20.0 (ISO 100)






Check out our Autumn In The High Sierra podcast - a video program that highlights this stunning scenery


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Peaceful Mountain: A Baby Panda Gets A Name

panda.jpgIt is Chinese tradition for a panda to be named on its 100th day of life. Perhaps this came about because captive pandas rarely survive more than a few weeks, but regardless, it's a day of celebration.

Today, the National Zoo in Washington, D.C. celebrated the naming day of it's newest black and white addition - Tai Shan.

Tai Shan, pronounced tie shahn and meaning "peaceful mountain," was the favorite in the zoo's online poll offering five choices approved by the China Wildlife Conservation Association. One of three names suggested by the Panda House staff, it garnered about 44 percent of more than 202,000 votes cast.

More at: Panda Cub's Birthday Present: A Name


You can read more about Tai Shan on this blog at:

Two More Weeks Til Baby Panda Cub Gets A Name

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October 10, 2005

Freakish Frog's Fate Foreboding

frog.jpg"The frog does not jump in the daytime without reason."
                -Nigerian Proverb

Bigger is better, right? Unfortunately, this is not true for the Goliath Frog. Yes, you heard me right, there's a frog by that name, and it can be more than a foot long sitting and more than three feet long when it's legs are fully extended, making it the largest frog in the world. Since their discovery in 1906, the Goliath Frog's size has made it the target of herp-crazy collectors and zoos throughout the world - today they net as high as $3000 US each. They're also hunted for food and medicinal purposes by some indigenous tribes.

Living only in swift-moving rivers bordering the rainforests of Cameroon and Equatorial Guinea in western Africa, the Goliath frog suffers from severe habitat loss. The endangered species' regulatory agency CITES does not currently recognize or protect Goliath frogs, so the wildlife trade continues, despite its status as vulnerable and their populations unknown.

Cameroon allows 300 goliath frogs to be exported each year, but luckily they're not easy to find; even the best professional collectors rarely catch more than a few dozen per trip.

More at: American Museum of Natural History: Goliath Frog

Very little is known about the Goliath frog - how many there are, how long they live, why they're so big are all still open questions. They don't croak or make noise, which makes them hard to find in the wild. They're hard to catch, partly because they're hard to find, but they also can jump up to ten feet per jump to evade capture. Unfortunately, once captured, Goliath frogs don't survive well in captivity. Protecting their native habitat is the only way to ensure their survival as a species.

THere are some great videos of Goliath frogs on the ARKive site.

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October 7, 2005

Gator Gluttony: A Python's Fatal Mistake

You buy a cute little baby Burmese python at the pet store for $20. It likes to weave itself through your fingers and watches TV from the comfort of its own personal ficus tree in the living room. It becomes a part of the family.

You feed it little mice from the safety of your bathtub, so it doesn't learn to hunt in its cage and bite you. Then you feed it bigger mice. After a while, you're feeding your snake dead rabbits.

It begins to occur to you that your python is going to live for up to 25 years, growing to 15-20 feet long and 100-200 pounds. By this point, your snake has it's own room.

At some point, you decide your pet is ruling your life. It's too expensive, and maybe it's scared you a bit with its aggressive feeding behavior. Perhaps you read a story about a python killing its owner, like Grant Williams or Rick Barber.

You decide it has to go, but where?

Few people are willing to take in such a large animal, especially a snake. The humane society won't take it, so you decide to let it loose in a nearby swamp. It's the only humane thing to do, right?

WRONG, WRONG, WRONG!

You have just aided and abetted the second most important force driving plant and animal endangerment and extinction in the world (the first being habitat loss). When an exotic species is introduced into a new environment, it's very unlikely to have native predators. Instead, its populations can grow, unchecked, while it devours the resources of the native species. For example, people keep dumping pet Burmese pythons into the Florida Everglades, and they're competing with the native gators for food and territory. Lately, visitors to the park have witnessed some very violent battles between the exotic snakes and the big scaly lizards.

The Burmese python is just one of thousands of non-native animal and plant species that have invaded the United States in the last decades. Florida teems with exotic creatures that have no business living there. Other regions have their own problems.

...

Burmese pythons are popular—and legal—pet snakes. In the past five years, the U.S. has imported more than 144,000 Burmese pythons.

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Since the mid-1990s park rangers have captured or killed 68 Burmese pythons in Everglades National Park. The pythons are now most certainly breeding in the park.

More At: Huge, Freed Pet Pythons Invade Florida Everglades

Rangers know that the pythons are breeding in the wild, as they have found snakes with umbilical cord scars. Tracking down and eradicating the pet python population in the park (alliteration at its finest, eh?) is a huge problem, but Florida park officials are trying a couple of methods.

The state agency's law enforcement division recently authorized its officers to kill exotic reptiles, specifically pythons, found on lands under its management, said Kevin Enge, a scientist with the commission.

...

In December scientists plan to capture and tag several pythons with radio-tracking devices to reveal their exact whereabouts inside the 1.5-million-acre (600,000-hectare) national park.

More at: Invasive Pythons Squeezing Florida Everglades

Introducing exotic species, especially formerly captive ones, can have other strange effects as well. Animals that have been hand-fed since birth (especially pre-killed stuff) may have odd feeding behaviors. Recently, a 13-foot Burmese python tried to eat a 6-foot long alligator. The gator was just too big, and the python's stomach just burst, making a very gruesome photography opportunity which has been featured on National Geographic's website:

Unfortunately for a 13-foot (4-meter) Burmese python in Florida's Everglades National Park, eating the enemy seems to have caused the voracious reptile to bust a gut—literally.

More at: Photo in the News: Python Bursts After Eating Gator

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October 3, 2005

Creepy Creature Camouflage

CamoSnake01.jpgAn animal's ability to survive and thrive, and therefore to reproduce, is key to the success of a species. Any advantage gained only serve to further this goal - whether by mutation, accident or purpose. A species adapts gradually, through the process known as natural selection. In the wild, an individual animal with any advantage lives longer. Consequently, the animal has the opportunity to reproduce more animals like it - passing the advantage to its offspring. Two of the most common and interesting adaptations that animals use to help them eat and keep them being eaten are camouflage and mimicry.

NATURAL CAMOUFLAGE

Blending In

seadragon.jpgAnimals, and plants for that matter, often try to make themselves look more like the landscape in which they live. They do this to avoid detection - sometimes because they want to make it harder for predators to see them, and sometimes because they don't want prey to know they're there to ambush them.

Leafy sea dragons look more like the drifting kelp that they live in than many of their sea-horse cousins. They've even adapted to move so slowly, they appear to drift as opposed to swim. Only by watching them very closely will you notice any locomotion or eye movement.

gws.jpgThe Great White Shark is another example of creature camouflage. I know, I can't seem to go more than five posts without mentioning this shark but hey, it's my favorite animal. The great white is not a big white fish, it's actually got a fairly sophisticated coloring to help it ambush predators - from above or below. Only it's underbelly is white, making it difficult to see if you look up at it. It's back and fins are actually a grey blue color, making it difficult to see it below you. This makes perfect ambush coloring for the world's largest predatory fish.

One thing that is interesting is that while mutations happen (so you'll might encounter a random characteristic), nature doesn't usually support adaptations that don't serve a purpose. In other words, every feature generally has a purpose; mutations that don't give the animal some advantage will not stick around in a healthy population of the species.

An animal will not develop any camouflage that does not help it survive, so not all animals blend in with their environment the same way. For example, there's no point in an animal replicating the color of its surroundings if its main predator is color-blind.

More At: How Animal Camouflage Works

Also, it's important to remember that camouflage doesn't have to be in the form of visual physical characteristics. Some animals, especially aquatic ones, also mask their scent from predators.

Now You See Me, Now You Don't!

Some animals have the ability to change their appearance to suit the environment and blend in better. Sometimes this change happens seasonally. For example, a rabbit (or a fox, for that matter) might have brown fur in the summer and white fur in winter. Other animals, like the anole lizard, can change their coloring on the fly to blend in with a leaf or bark color, unlike chameleons, which change their color based on mood.

Disruptive Appearances
Some creatures use coloring to protect themselves in other interesting ways... Some animals change their appearance to make them look bigger, by puffing out their chests or fluffing their fur. Other animals take this further by changing their coloring to confuse predators and prey. The disruptive coloring mechanism can often explain some of the oddest animal coloring phenomena in nature.

In Africa, one of the laws of nature is safety in numbers. A lone zebra may seem out of place against the earthy colors of the savannah, but the animal's striped coloring provides an excellent example of disruptive appearance.

To a lion, a herd of zebras doesn't look like a whole bunch of individual animals, but more like a big, striped mass. The vertical stripes all seem to run together, making it hard for a lion to stalk and attack one specific zebra. The stripes may also help a single zebra hide in areas of tall grass. Since lions are colorblind, it doesn't matter that the zebra and surrounding environment are completely different colors.

More At: How Stuff Works: The Element of Disguise and How do a zebra's stripes act as camouflage?



MIMICRY

Any animal that has evolved to resemble another successful species in order to fool predators or lure prey is called a mimic and you'll often see examples of mimicry - especially in insects. There are four basic kinds of mimicry.

Me, Myself And I

HeadLizard01.jpgThe first type of mimicry is probably the weirdest. When an animal mimics some part of it's own body, it's called automimicry. I've seen this most often in reptiles that seem to have a head at both ends. A bird might attack a poisonous snake or lizard, but if it appears to have heads at both ends, it's unclear which end is "safe" and also which direction the prey is likely to run - this confuses the bird and it's likely to try for easier prey elsewhere.

If Only Looks Could Kill

butterflyeye.jpgBatesian mimics take on the look of a species with an attribute that discourages predation but does not actually have that attribute themselves. In this instance, a yummy-tasting frog may take on the colorings of a poisonous frog in order to deter predators, but it's still not poisonous itself. Another example of Batesian mimicry is the Aegeria moth, which resembles a yellowjacket wasp, but has no stinger. Some butterflies have a marking on each wing that looks like the eye of a large animal, and there's even a caterpillar that looks like a snake!

More Than Skin Deep

Müllerian mimics resemble the successful species but also come to share the anti-predation attribute. In this way, both species benefit from the advertisement of their unpalatability to predators with less loss of life to a single species. A good example of Müllerian mimicry is the honeybee, because it shares a similar appearance with the yellowjacket wasp, and they both can sting.

A Wolf In Sheep's Clothing

Lastly, there are aggressive mimics. Like the Big Bad Wolf when he dressed up like Little Red Riding Hood's grandma, aggressive mimics resemble something harmless in order to lure unsuspecting prey. Malaysian preying mantids resemble flowers, which lure bees to be eaten. There's also the ultimate femme fatale, the Photuris firefly female will mimic the blinking signal of other species of firefly, luring the unsuspecting males to be eaten. If you've seen the movie Master & Commander, you'll know about the walking stick, an insect that looks like an ordinary twig.


You can find some great pictures of animals known for their camo and mimicry adaptations at Wayne's Word: Photos Of Ecological Adaptations and The Wild Ones: Insect Camouflage and Mimicry.

Photographer Art Wolfe has also published a new book entitled Vanishing Act in which he disregards the standard wildlife photography conventions of capturing dramatic action and instead shows us how they normally appear in nature - trying to blend in. You can see some of his pictures in Smithsonian Magazine: Hiding in Plain Sight.

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October 2, 2005

Canis Africanus

prints1.jpgEveryone knows about the big cats of Africa - the lion, the leopard, the cheetah. The canine species are less well known, and yet most of the canine species of Africa are much more threatened than the big cats.

Canidae is the family of carnivorous and omnivorous mammals commonly known as canines, and is broken into two rather murky groups - "true dogs" and "foxes". Canids are digitigrades - animals that walk on their toes, which is generally faster and quieter than other methods and therefore a beneficial feature for a stealth predator. Dogs, wolves, foxes, coyotes, and jackals. Although hyenas look like rather large wild dogs, they are a separate biological family more closely related to mongooses and meerkats.

Now, you may have heard of the plight of the African wild dog or the cute little bat-eared fox. I've seen black-backed jackals munch on giraffe alongside a hyena pack and a young male lion. But until recently, I'd never heard of a wolf existing in Africa.

The Ethiopian Wolf, which has also been misidentified as a jackal and a fox - for its small size and bright red fur, is perhaps the rarest and most endangered canid in the world. Found in Africa's alpine regions, above 10,000 feet, a small population struggles to avoid extinction. According to Wikipedia, only about seven packs/populations remain in the wild, totaling about 500 mature animals. The wolves are facing a myriad of threats - from encroachment and farmers to inbreeding and cross-breeding with domestic dogs to disease. Back in 1990, a single rabies outbreak was transmitted from domestic dogs, reducing the largest known population of Ethiopian wolves from about 440 wolves to less than 160 in just two weeks time.

The Ethiopian Wolf Conservation Programme was established to study and protect the species. They provide more information about the wolf than I have been able to find anywhere else on the web. They've also got lots of great pictures. Recently, National Wildlife Magazine did a piece on the African wolf, including some really beautiful photography.

In contrast to other wolf species, Ethiopian wolves primarily hunt alone. Excellent predators, they use a variety of strategies to catch prey. Sometimes they stalk small rodents, pouncing on the victims. Other times, they dig up soil to get at a nest of young, or pat the ground to flush rats out of a hole, nabbing the animals as they try to escape. True to their wolf genes, the predators do occasionally group together to hunt larger prey—a young mountain nyala or reedbuck, for example—although these attempts are usually unsuccessful.

The predators' unusual hunting strategies, combined with other non-wolflike qualities, once caused confusion about the species' identity. At first, the animals were considered jackals, and later foxes: They forage alone and bark like jackals, but their orange-red coats resemble those of foxes. Recent genetic evidence, however, tells a different story, confirming the animals are indeed wolves, which split from their closest living relatives, gray wolves, just over 100,000 years ago.

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Ethiopian wolves are also susceptible to inbreeding and other problems associated with small populations. The species now has the lowest genetic diversity of any carnivore in the world. In addition to genetic problems, small populations are vulnerable to chance events. If a population of ten wolves, for example, produces two successive litters in which only male pups survive, it would become predominantly male and no longer be viable.

More at: National Wildlife Magazine: Africa's Lone Wolf

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October 1, 2005

The Turtle With Two Heads

turtle2.jpgMore lucky than a four-leaf clover? Hell, ya! This story reminded me of one of my favorite Aquabats songs... The Cat With Two Heads.

Science brings gifts of convenience
To the modern man
Modern man then continues
Continues to expand
But what happens when man
Creates something oh so wrong
Nature bites back in a big way
Good heavens what have I done!

I was in my laboratory creating
what i thought would be
something great for the world,
a two headed cat
you can pet one kitty's head
and pet the other kitty's head,
but little did i know the power
of atomic energy would create
a twoheaded man eating monster!

I kept it in a box
I watched it grow a lot
It chewed right through the lock
And ate all the new kids on the block.

--- The Aquabats

More at: The Aquabats Website

Ok, so the turtle wasn't a giant man-eating monster. It's just a little guy, really little. The turtle is now living at the National Aquarium of Cuba.

A policeman has made an unusual discovery near a river in Cuba - a turtle with two heads.

The tiny turtle is thought to be around a week old and was found near one of the country's most contaminated rivers.

More at: CBBC Newsround | Animals | Two-headed turtle found in Cuba

I've always wanted a pet turtle to live in my backyard pond. I envision growing a little garden of veggies for it to munch away in, but around here we have too many cats around here... one-headed ones that is...

Note: The picture above is not of the actual turtle. Click the CBBC link to see the real turtle. I was just screwing around in photoshop making myself a new desktop background.

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The Zoo Report Card

I love going to the zoo, especially to practice my wildlife photography in times where I can't leave home and travel into the wild for one reason or another.

I've been to zoos and aquariums all over the world - the US, Europe, Africa... Some were fantastic. Others were only ok. My opinion of a good zoo/aquarium is based on several simple factors: animal health, cleanliness, knowledge dissemination, and lastly, my visit can sometimes be colored by some negative experience with crowds or weather, but generally I'm pretty laid back about this kinda stuff.

asianrhino.jpgZoos and aquariums are expensive endeavors. It's very challenging to keep animals - especially exotics - healthy and happy in captivity. The San Diego Zoological Society has the well-deserved honor of running the best zoo system in the United States. They run the San Diego Zoo (click to see pics) in downtown Balboa Park as well as the San Diego Wild Animal Park located about 30 miles outside of town on a much larger plot of land. The Wild Animal Park is by far my favorite place to see animals - they've got huge enclosures which make them harder to see "up close and personal" but the animals are clearly well cared for as evidenced by the sheer number of baby animals one can see there as the animal park also serves as a place for stressed out downtown zoo animals to go for some private time as well as a major breeding facility.

shark.jpgBut an excellent facility need not be large. Some of the best zoos and aquariums in the world got there by specializing in a certain area of zoology in order to provide the care and funding needed to maintain the best exhibits possible. The Monterey Bay Aquarium is a great example of this: they leave the "show" animals to the theme parks like Marine world and focus on the smaller animals of the Monterey Bay and beyond. You won't find the normal aquarium fodder of whales, dolphins, walrus, or seals here. Instead, you'll find windows into the bay - a kelp forest teaming with wildlife, frisky sea otters at play, and the mysterious deep open-water community in the one-million-gallon Outer Bay exhibit.


gorilla.jpgAnother great example of a zoo specializing is the Jersey Zoo in the British Channel Islands. Run by the Durrell Wildlife Conservation Trust, the Jersey Zoo focuses on primates - everything from the smallest lemur to the western lowland gorilla. Frankly, I've never seen primate exhibits that could rival this zoo, even in much larger facilities.

nationalzoomonkeysign.jpgSome of my least favorite zoos? Well, I was very unimpressed with the National Zoo in Washington DC. I liked the price (free) and the escaped golden lion tamarins living in the trees and stealing people's food was amusing, but half the exhibits were empty and closed off. Hard to enjoy a zoo without any animals. Perhaps next time...

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