Agriculture
Springing forward
Watching out for vultures
Making the most of a meal
Amphibians
Frogs and Toads
Newts
Toads
Animals
Awake at Night
A Whale's Amazing Tooth
Revenge of the Cowbirds
Behavior
Surprise Visitor
The Snappy Lingo of Instant Messages
Monkeys in the Mirror
Birds
Hawks
Cardinals
Kingfishers
Chemistry and Materials
A New Basketball Gets Slick
Earth-Friendly Fabrics
Atomic Drive
Computers
Batteries built by Viruses
Games with a Purpose
Look into My Eyes
Dinosaurs and Fossils
Dino-Dining Dinosaurs
From Mammoth to Modern Elephant
The man who rocked biology to its core
E Learning Jamaica
2014 GSAT Results for Jamaican Kids
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
Results of GSAT are in schools this week
Earth
Rodent Rubbish as an Ice-Age Thermometer
Earth from the inside out
Vitamin D-licious Mushrooms
Environment
The Birds are Falling
Snow Traps
Cactus Goo for Clean Water
Finding the Past
Words of the Distant Past
If Only Bones Could Speak
The Puzzle of Ancient Mariners
Fish
Dogfish
Perches
Tuna
Food and Nutrition
Yummy bugs
Strong Bones for Life
Allergies: From Bee Stings to Peanuts
GSAT English Rules
Order of Adjectives
Problems with Prepositions
Who vs. Whom
GSAT Exam Preparation Jamaica
March 21-22, 2013: Over 43,000 students will take the GSAT Exam
2014 GSAT Results for Jamaican Kids
GSAT stars reap scholarship glory
GSAT Exams Jamaica Scholarships
GSAT stars reap scholarship glory
2014 GSAT Results for Jamaican Kids
Results of GSAT are in schools this week
GSAT Mathematics
Deep-space dancers
Detecting True Art
10 Common Mistakes When Preparing for the GSAT Math Test
Human Body
Spitting Up Blobs to Get Around
Hear, Hear
Hey batter, wake up!
Invertebrates
Sea Urchin
Millipedes
Lice
Mammals
Jaguars
Doberman Pinschers
Sphinxes
Parents
Children and Media
The Surprising Meaning and Benefits of Nursery Rhymes
Raise a Lifelong Reader by Reading Aloud
Physics
Invisibility Ring
The Mirror Universe of Antimatter
Strange Universe: The Stuff of Darkness
Plants
Flower family knows its roots
Hungry bug seeks hot meal
Fast-flying fungal spores
Reptiles
Chameleons
Rattlesnakes
Black Mamba
Space and Astronomy
Zooming In on the Wild Sun
A Great Ball of Fire
A Dusty Birthplace
Technology and Engineering
Space Umbrellas to Shield Earth
Smart Windows
Roll-Up Computer Monitors to Go
The Parts of Speech
Pronouns
What is a Noun
What is a Preposition?
Transportation
Ready, unplug, drive
How to Fly Like a Bat
Middle school science adventures
Weather
Arctic Melt
Earth's Poles in Peril
Recipe for a Hurricane
Add your Article

Polar Bears in Trouble

Alaskan polar bears are masters of ice. Even during the frigid days of winter, these furry white creatures don't hibernate in cozy dens, like other bears do. Instead, they go north, hunting for seals living in the ice-covered water. In recent years, however, Earth's climate has been getting warmer, and ice near the Poles has been melting. Now, a new study by scientists at the U.S. Geological Survey (USGS) in Anchorage, Alaska, shows that disappearing ice is changing polar bear behavior. In particular, slightly more than half of pregnant polar bears used to give birth in dens on solid blocks of ice that were floating out at sea. Today, they're more likely to dig their dens on or near land. The consequences of the shift are unknown. When the scientists began this study, their goal was to see whether they could use radio collars that communicate with space satellites to see if bears were snuggled in dens. The collars worked. Over the course of testing, however, the researchers discovered some surprising data concerning the locations of these dens. Between 1985 and 1994, 62 percent of the dens that the satellite system detected were on floating sea ice. Between 1998 and 2004, however, only 37 percent of dens were floating out at sea. Disappearing ice is the best explanation for the shift, the researchers say. Other studies have shown that 27 percent of sea ice in the Arctic that stays frozen from year to year has disappeared during the past 30 years. So there's now much less space for dens. Moreover, as this permanent ice melts, the remaining ice becomes less stable. These conditions are unappealing to mother polar bears, who want a safe place to give birth and keep thir cubs in a protected den for several months. "If you're a mother bear, you probably want to be on ice that's pretty doggone stable," says USGS researcher Steven Amstrup. For now, Alaska's polar bears seem to prefer returning to land rather than taking the risk of giving birth on shaky ice. That solution might not work forever, however, especially if the ice keeps melting. "The biggest concern," Amstrup says, "is that [as] the ice continues to retreat, there may come a time when bears can't return to land." For polar bears, the future is uncertain, says polar bear researcher Ian Stirling of the Canadian Wildlife Service, based in Edmonton, Alberta. "As the climate is warming and we're losing ice," Sterling says, "you don't have to be a rocket scientist to know that that's going to have a significant negative effect on an animal that depends on ice for life."—Emily Sohn

Polar Bears in Trouble
Polar Bears in Trouble








Designed and Powered by HBJamaica.com™