Photo: Wolfpix

Impetus

The urge to feed and breed drives birds across oceans, mountains, and the equator. Some migrations originated after the last ice age in response to the retreat of ice sheets in areas where birds could expand their ranges to exploit food resources and decreased competition during the breeding season.

Then, they flew south again for the winter when temperatures dropped and the flowers and insects on which they fed were gone.

Endurance

Photo: thefixer

Some birds fly for several days in a row without stopping, sleeping, or eating! One of the tiniest migrants, the Ruby-throated Hummingbird, flies 900 kilometers nonstop across the Gulf of Mexico with the benefit of aerodynamic flocks like most species.

The Bar-tailed Godwit was named the “endurance champion of the animal kingdom” after completing a nine-day nonstop 11,000 kilometer flight across the Pacific Ocean. This sort of journey requires consuming energy at around eight times their resting metabolic rate.

By comparison, a professional cyclist may function at around five times BMR… but only for a few hours.

Physiology

Even birds get hormonal! Before migration, birds undergo hormonal changes that literally change their physiology. Changes in hormone levels cause them to fatten up and build energy reserves to sustain flight. Then, just prior to departure, the digestive system shrinks because the birds may not eat again for several days.

Conversely, the flight muscles and heart increase in size and capacity. The birds also molt into their stunning breeding plumage. The bright, beautiful colors help them attract a mate and the fresh new feathers are strong for sustained flight.

Biological Clock

Migratory birds have internal clocks cued by changes in day length around the spring and fall equinoxes. The instinct is so great that even migratory birds held in captivity can get fat, molt, and exhibit Zugunruhe, or migratory restlessness, during migration season.

They flutter their wings and try to fly in the direction in which they would normally fly. But when the captive birds are exposed to unnatural patterns of daylight, they do not get Zugunruhe, demonstrating their innate response to environmental cues.

On the other hand, juvenile birds do not molt into breeding plumage or migrate even though they are experiencing the same environmental cues because they are pre-pubescent and have not experienced the changes in hormone levels yet.

Navigation

How do the birds know in which direction to fly? How can they correct for winds and storms that blow them off course? Birds have sun, star, and magnetic compasses. The sun and stars make predictable rotations across the sky, providing direction both day and night.

When the sky is cloudy and birds cannot see the sun or stars, they rely on their sense for the Earth’s magnetic field. They are sensitive to the angle at which lines of magnetic force meet the Earth’s surface, which changes at different latitudes.

Some birds that were captured, shipped to areas outside of their flyway, and released have still been able to reorient themselves and fly to their original destination!

Clever Chicks

Photo: mikebaird

Once shorebird chicks have hatched and are feeding on their own, the parents fly back to the southern hemisphere for the winter. When the chicks have developed their wings and feathers, they too make the journey south.

The amazing thing is that they have never made this trip before. And they do not have an experienced bird to show them the way. Somehow, they just know where to go.

They fly up to 10,000 km over land or water they have never seen before. The European Cuckoo migrates across the world without ever having contact with its parents, providing evidence that birds can navigate by instinct.

Despite their amazing adaptations, the birds still face many threats on their journey. Bad weather systems, predators, and habitat destruction prevent as many as half of migrating birds surviving to their destination. When they arrive at their stopover points, they are starving and exhausted from days of flight and fasting and depend on those rest areas persisting from year to year.

Because the birds are international species, conservation efforts require international cooperation. Things you can do to protect migrants include keeping your cat indoors, turning off lights in office buildings at night, buying shade-grown coffee, and keeping bird baths free of mosquito larvae since West Nile Virus is an increasing threat to birds in North America.

Join a conservation organization such as the National Audubon Society or Birdlife International, which studies, conserves, and holds festivals for the return of migratory birds.

Community Connection:

Want to see birds at rest and in flight? Mary has identified the 10 Birding Hotspots for bird watchers.

Feature photo by pingnews.com. Photo above by seanmcgrath.

Do you think tropical diseases only occur in developing countries? Think again.

The World Health Organization (WHO) says diseases are spreading to temperate regions thanks to global warming.

Warmer temperatures and greater moisture extend the geographic range and season for disease-vector organisms such as insects and rodents. Below are diseases that could have you feeling the sting of global warming.

Malaria

Malaria is spread by the Anopheles mosquito infected with the Plasmodium parasite. Warmer and wetter climates trigger increased mosquito abundance, biting rates, activity level, and accelerated incubation of their parasites. Winter temperatures must drop below 16ºC to prevent a malaria outbreak the following spring.

The U.N. Intergovernmental Panel on Climate Change (IPCC) projects that warmer temperatures will put 65% of the world’s population at risk of infection—an increase of 20%. This news is especially frightening in light of increased resistance to the chloroquine treatment drugs. Malaria has already hit Texas, New Jersey, Michigan, and New York.

Photo by otisarchives2.

Dengue Fever

Dengue fever is spread by the Aedes mosquito infected with the Flavivirus virus. The geographic range of the mosquito is limited by freezing temperatures that kill larvae and eggs, thus limiting transmission to tropical and subtropical regions.

But studies by the U.S. Environmental Protection Agency (EPA) and U.S. Department of Agriculture predict dengue’s encroachment upon temperate regions due to small increases in temperature.

The mosquito has spread as far north as Chicago and the Netherlands and to higher elevations of the Andes. With no vaccine, “breakbone” fever is considered the most serious mosquito-borne viral disease affecting humans.

Encephalitis

Encephalitis is an arthropod-borne disease present in many forms, including St. Louis, equine, La Crosse, and West Nile. New York experienced outbreaks of both West Nile Virus (WNV) and St. Louis encephalitis in 1999 during its driest and hottest spring and summer in a century.

Those weather patterns favorable to outbreaks—heat and drought followed by heavy downpours—will likely occur more often with global warming. Small stagnant pools of water that accompany drought are big enough to support breeding mosquitoes but not populations of the frogs that prey on them.

Photo by pingnews.com.

Bubonic Plague

Bubonic plague is spread by rodents and their fleas infected with the bacterium Yersinia pestis. A study in the Proceedings of the National Academy of Sciences reports that global warming promotes outbreaks of “black death.”

A 1ºC increase in springtime temperatures is predicted to lead to more than a 50% increase in the prevalence of the bacterium.

A study in the American Journal of Tropical Medicine and Hygiene reports a 60% rise in plague cases in New Mexico following wetter than average winters and springs. Wetter conditions enhance food resources for rodents and promote flea survival and reproduction.

Cholera

Cholera is a waterborne disease present in drinking water and food contaminated with the bacterium, Vibrio cholerae. The WHO links the spread of cholera with increases in sea surface temperature, sea level rise, and El Niño-Southern Oscillation.

The U.S. EPA reports that algal blooms, which can be accompanied by cholera, become more frequent with warming temperatures. Cholera-harboring zooplankton also proliferates in warmer water temperatures.

Photo by otisarchives2.

What you can do

The IPCC warns that global warming will result in human mortality from infectious disease. Unlike the typical U.S. approach of emergency response to epidemics, a preventive approach would preclude unnecessary suffering, infection, and loss of life.

The Centers for Disease Control and Prevention (CDC) provides information on prevention, vaccines, and epidemics. Below are things you can do to reduce your chance of infection.

Often policymakers do not take action on environmental issues unless it affects human health so maybe this will be their wake-up call to do something about global warming.<

Feature photo by markgee6 Photo by leonardlow

1. Great Barrier Reef

Flourishing with more than 1,500 fish species and the endangered hawksbill turtle, Australia’s Great Barrier Reef is the largest coral reef ecosystem in the world. But the Blue Outback is fading to white due to coral bleaching. Increasing carbon dioxide and temperature levels are projected to render the reef functionally extinct by 2030.

Photo by warrenh

2. Amazon Rain Forest

Teeming with millions of species and one-fifth of the world’s fresh water, the Amazon is the world’s largest tropical rainforest. However, global warming and deforestation are reversing the forest’s role as a carbon sink, converting 30-60% of the rainforest into dry savannah. Projections show the forest could disappear completely by 2050.

3. Yangtze Region

Shrouded in the dense mist of the forests of the Yangtze region of China is the endangered giant panda. But downtown, a rapidly developing economy and commercial logging industry cause flooding and habitat destruction. Nearby, the Three Gorges Dam, the largest dam in history, is destroying the Yangtze River ecosystem.

4. The Everglades

The shrubby wetlands of the Everglades are the only place in the world to find the endangered Florida panther. But the Everglades cover only half the land area they used to. This “River of Grass” has been carved into a grid of canals and crops to feed and water the encroaching cities.

Photo by bobjagendorf

5. Cape Floral Region

Blooming with 6,200 endemic plant species, the Cape Floral Region of South Africa encompasses one of world’s six floral kingdoms. Global warming is projected to increase mean annual temperatures by 1.8 ºC by 2050 which is bad news for the 1,400 species that are critically endangered and sensitive to small changes in climate.

6. Congo Basin

Chopped into logs and tilled into agriculture, the Congo Basin rainforest is projected to disappear by 30% by 2030. As the human population grew over the past decades, the endangered mountain gorilla population dwindled to 700 individuals. As the world’s second largest tropical rainforest, the basin regulates climate and water flow.

7. Madagascar

Because Madagascar broke off from Gondwanaland 160 million years ago, its species evolved in isolation and occur nowhere else on earth. Deforestation, agriculture, and erosion may cause lemurs and chameleons to go extinct before the end of the century. The aye-aye, silky sifaka and Goodman’s mouse lemur are considered three of the most evolutionarily distinct and globally endangered animals.

Photo by plizzba

8. Mt. Kilimanjaro Glacier

With its conspicuous snowy peak standing out over the surrounding savannah, Mount Kilimanjaro is topped with a glacier uniquely situated near the Equator. Persisting for over 10,000 years, the glacier suddenly retreated by 82% since 1912 due to global warming. At current rates, the glacier could melt completely by 2020.

Photo by tambako

9. The Phillipines

With only 7% of its original forest still standing, the Philippines is one of the world’s most biologically-rich yet most endangered areas. The remaining forests are disappearing at a rate of 1186 acres per day. Illegal logging is a $700 million per year business, resulting in erosion and flooding, as evidenced by the 2004 landslides.

10. The Himalayan Glaciers

The Himalayan glaciers are melting faster than ever at a rate of 33-49 feet per year due to global warming. Melting glaciers could flood India, China, and Nepal and destroy habitat for the endangered snow leopard. Unpredictable weather is creating dangerous conditions for climbers of Mt. Everest.

Photo by mckaysavage

All over the world, wildlife is being replaced by cars and rivers are being redesigned by dams and canals. Many natural wonders may fall victim to concrete jungles and flooded cities within 50 years.

If our generation does not act, the next generation may never see these treasures. Conservation efforts must engage local communities and governments as well as the global community.

To help, contribute to the local economy rather than a foreign-owned resort when traveling to sensitive areas.

Community Connection!

You can connect with hundreds of grassroots organizations on Matador!

A list of NGOs focusing on Environmental and Conservation issues can be found here.

To explore opportunities with organizations working to stop natural wonders from disappearing completely, visit Amazon Conservation Association, and Flor de La Amazonia in the Amazon Basin and ReefDoctor in Madagascar.

Feature photo by pingnews Photo by kenbondy

The U.S. Fish and Wildlife Service lists 1237 endangered species. The following ten species are key because of their roles in the ecosystem and and dangerously low numbers.

Mountain Gorilla

Photo by mrflip

Africa’s mountain gorilla (Gorilla beringei beringei) is the largest and most powerful primate, but is very peaceful and sociable,
despite their portrayal in movies such as King Kong and Tarzan.

Gorillas are our closest relative after chimpanzees with an almost 98 percent DNA match. The remaining 600 individuals face habitat loss through deforestation, poaching, circus use, effects of political unrest, and human diseases such as measles.

Florida Panther

Once prevalent throughout the southeastern U.S., the Florida panther (Puma concolor coryi) is now restricted to south Florida. Cities and farms dump pollutants into waterways that feed the Everglades, an ecosystem that occurs nowhere else on earth. To boost numbers and prevent inbreeding among the remaining 50 individuals, humans bred the Florida panther with the Texas panther resulting in a genetically different hybrid.

Giant Panda

Photo by tanukigirl

China’s giant panda (Ailuropoda melanoleuca) habitat is situated at the top of the Yangtze Basin, one of the world’s most critical regions for biodiversity conservation. Because of their notoriously low sex drives, captive pandas are shown pornographic videos to encourage mating. After more than a century of debate, recent DNA analysis concludes that the giant panda is more closely related to bears than to raccoons.

Beluga Sturgeon

The ancient beluga sturgeon (Huso huso), while persisting for over 200 million years, may not outlast current threats. Its caviar is one of the world’s three most expensive foods, selling for over $100 dollars per ounce and encouraging illegal trade and poaching.

Dams along the Volga River block migration from their breeding ground to the Caspian Sea. Historically, Belugas lived for 75 years, weighed more than 2 tons and grew to 28 feet in length. Now, the typical adult is younger than 18 years old and weighs only 77 pounds.

Blue Whale

Photo by scotts101

Antarctica’s blue whale (Balaenoptera musculus) is the largest creature on earth. The largest terrestrial animal, the African elephant, could stand on the whale’s tongue. UV radiation through a hole in the ozone layer depletes its food source, zooplankton. The blue whale is the loudest animal on earth, using low-frequency rumbles to communicate across hundreds of miles of ocean. Click here to listen to its call.

Blue Poison Dart Frog

Photo by upton

The blue poison dart frog (Dendrobates azureus) is one of the most brilliantly colored animals on the planet. Humans harness the poison as a potential ingredient in painkillers and the indigenous Chocó peoples of Columbia dab it on blowgun darts for hunting. The tiny frogs inhabit South American rainforest, which is disappearing at a rate of four football fields per minute.

Southern Cassowary

The ancient southern cassowary (Casuarius casuarius) is a helmeted flightless bird in Australia’s Wet Tropics. As voracious fruit-eaters, they spread seeds, regenerating the rainforest in the face of deforestation. Even though the large birds weigh 130 pounds, they fall prey to non-native feral pigs, which were also responsible for the extinction of the dodo.

Loggerhead Turtle

The loggerhead turtle’s (Caretta caretta) habitat extends through many countries, requiring international cooperation and treaties. Despite requirements to install turtle excluder devices on fishing gear in some countries, turtles continue to die as bycatch in countries without such measures. Pacific loggerheads migrate over 7,500 miles from their nesting habitat in Japan to their foraging habitat off the coast of Mexico.

Polar Bear

Photo by Amanda Graham, 2006

The world’s largest terrestrial carnivore, Arctic polar bears (Ursus maritimus) are threatened by global warming. They must fast longer in the summer due to melting sea ice. In 2007, the U.S. Fish and Wildlife Service proposed to list the polar bear as a threatened species under the Endangered Species Act. As of May 14th 2008, the Polar Bear was listed on the ESA. The decision was crucial as 29.7 million acres of the Chukchi Sea, which supports polar bear populations, are set to be opened to oil and gas activities.

Elkhorn and Staghorn Coral

Elkhorn and staghorn coral (Acropora palmata and A. cervicornis) are the first species to be recognized as threatened by global warming. The new status provides leverage in future fights against threats to other habitats from global warming. Coral reefs provide habitat for thousands of species of fish.

What can be done?

Through pollution, habitat degradation / depletion, and worldwide environmental impact, humans are largely responsible for the extinction and endangerment of species. Thus it is humans who can help preserve animals and habitat by changing behaviors.

Ride your bike. Join your local Audubon chapter. Create backyard wildlife habitat. Write to your representatives. When corporate behavior cannot be changed by legislation, use your consumer power to boycott. The best approach to conserving wildlife is to conserve habitat. Keeping “common species common” prevents wildlife from becoming too rare and costly to restore.