Blue-Footed Boobies Declining in the Galapagos

The animal's numbers have dropped more than 50 percent in less than 20 years.

The population of blue-footed boobies - the seabirds with characteristically colorful feet - has been declining in the Galápagos islands.

The birds' numbers have dropped more than 50 percent in less than 20 years, according to a study published Monday (April 21) in the journal Avian Conservation and Ecology. The researchers speculated that a lack of sardines, a source of food for the boobies, might be to blame for the decline.

The researchers first noticed the decrease in the booby population in 1997.

"Until 1997, there were literally thousands of boobies at these breeding sites, and hundreds of nests full of hatching chicks," study author Dave Anderson, a professor of biology at Wake Forest University, said in a statement. [In Images: 100 Most Threatened Species]

"Then, suddenly, the boobies just weren't there," Anderson said, adding that, in a few cases, the birds had attempted to breed, but most did not produce offspring.

Recently, a team of seabird biologists monitored the birds' breeding at four of the largest blue-footed booby breeding colonies in the Galápagos. The researchers discovered that between May 2011 and June 2013, the boobies bred little or didn't breed at all, and the scientists found only 134 fledgling birds during the study period.

The research team also discovered that there were only about 6,423 boobies living in the Galápagos in 2012, which was less than a third of the estimated number in the 1960s.

Previous research on booby colonies has shown that the seabirds can breed only during periods when their diet consists almost exclusively of sardines. In the new study, the researchers found that sardines constituted less than half of the blue-footed birds' current diet.

This suggests the surviving boobies may be getting enough sardines to live, but not to breed, the researchers said.

The shortage of sardines in the Galápagos region remains unexplained. It could be due to overfishing, or sardines leaving Galapagos waters due to climate change or other pressures, said Johannah Barry, president of the Galápagos Conservancy.

Because the boobies are not breeding, young birds are not replacing older ones, which means that the population as a whole is aging, the researchers said. And it is even harder, or impossible, for older birds to raise offspring, than it is for younger ones.

So far, research has not directly linked the booby population decline to human activity, Anderson said. "But if humans are in fact contributing to this decline, we need to get to the bottom of it now rather than five years down the road, when you have the equivalent of 75-year-old humans trying to breed," he said.

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The blue-footed booby's numbers have dropped more than 50 percent in less than 20 years.

Lonesome George - the Last Pinta Island Tortoise

June 25, 2012 -

Lonesome George, the last Pinta Island giant tortoise and celebrated symbol of conservation efforts has died. George passed away in the Galapagos Islands with no known offspring after several attempts at breeding George with other similar tortoise species, according to AFP. Lonesome George's longtime caretaker, Fausto Llerena, found the giant tortoise's remains stretched out in the "direction of his watering hole" on Santa Cruz Island, according to AFP. Estimated to be more than 100 years old, the creature's cause of death remains unclear and a necropsy is planned. Lonesome George was discovered on Pinta Island in 1972 at a time when giant tortoises of his type, Geochelone nigra abingdoni, were already believed to be extinct, according to AFP. The following is a look at other at risk animals in the world.

NEWS: Extinct' Giant Tortoise Found on Remote Island

Animals at Risk Since the Endangered Species Act's passage 33 years ago, 1,800 species have been listed as endangered and nine have become extinct. ARKive, a collection of the world's best wildlife films and photographs, gathered together a list of the most at risk animals. The Tiger has undergone large population declines across Cambodia and the rest of Asia, according to ARKive.

Blue Whale (Endangered) Once hunted nearly to extinction, the blue whale is the largest animal to have ever lived, growing to around 27 meters (88.5 feet) long and weighing up to an astounding 120 tons. It also produces the loudest call of any animal on Earth. Although hunting of the blue whale was banned in 1966, the recovery of this magnificent marine mammal has been exceptionally slow.

Giant Panda (Endangered) The giant panda is universally admired for its appealing markings and seemingly gentle demeanor. A charismatic conservation icon, the giant panda is threatened by habitat loss, with large areas of China’s natural forest being cleared for agriculture, timber and firewood to meet the needs of the large and growing human population.

Tiger (Endangered) The tiger is one of the most emblematic symbols of conservation today, and its distinctively patterned coat and fearsome reputation make this species instantly recognizable. However, the tiger is facing the grave threat of extinction due to illegal poaching and habitat loss.

Sumatran Orangutan (Critically endangered) The name of the Sumatran orangutan means "person of the forest." The biggest threat to the Sumatran orangutan is the loss of its forest habitat, with around 80 percent of the forest on Sumatra vanishing in recent years due to illegal logging, gold mining and conversion to permanent agriculture, in particular, palm oil plantations.

Black Rhinoceros (Critically endangered) Contrary to its name, the black rhinoceros is actually grey in color. It was hunted almost to the brink of extinction for its impressive horn, which can grow up to 60 cm (23.6 inches), largely due to the demand for horn in Chinese traditional medicine and for traditional dagger handles in Yemen.

Philippine Eagle (Critically endangered) The striking Philippine eagle is the world's largest eagle and also one of the world’s most threatened raptors. The destruction of its habitat is the main cause of its dramatic decline, with vast tracts of tropical forests in the Philippines having been cleared for commercial development and for shifting cultivation.

Kakapo (Critically endangered) As the world’s only flightless parrot, the kakapo is a truly unique bird which is threatened by introduced species in its native home of New Zealand. Conservationists have taken the drastic measure of removing all surviving kakapo to predator-free islands, so far averting the extinction of this remarkable bird.

Hawksbill Turtle (Critically endangered) The hawksbill turtle possesses a beautiful marbled shell, which has been exploited for thousands of years as the sole source of commercial tortoiseshell. Illegal demand for its shell, and for its eggs, meat and even stuffed juveniles as exotic gifts, have led to the dramatic decline of this species over the last century. A further threat to the hawksbill turtle is global climate change.

Lemur Leaf Frog (Critically endangered) The lemur leaf frog is specially adapted for a life in the trees with adhesive pads on its toes. Eggs are laid on leaf surfaces and when hatched the larvae are washed off or fall into water below. This nocturnal tree frog was once considered to be a reasonably common species in Costa Rica, but it is threatened by the loss of its forest habitat and most populations in Costa Rica have recently disappeared.

Scalloped Hammerhead (Endangered) Forming impressively large schools, female scalloped hammerheads gather in the Gulf of California during the day, around underwater mountains known as seamounts, where they perform a wide range of behaviors yet to be understood. The scalloped hammerhead is under threat due to fishing pressures and in particular is a victim of shark finning. ANIMAL PLANET: Endangered Species Guide