creatures

A starfish to the rescue

June 3, 2025 By EarthWise Leave a Comment

Beginning in 2013, a mysterious disease associated with a marine heatwave decimated the population of sunflower sea stars. Those huge, colorful 24-armed starfish thrived along the Pacific Coast between Alaska and Baja California. But in fairly short order, nearly six billion of the creatures perished, amounting to 94% of the global population. California lost 99% of its sea stars to the wasting disease.

The result was an ecological disaster. Sunflower sea stars are carnivorous and purple urchins are the mainstay of their diet. Without sea stars to balance the food web, the urchin population exploded. Urchins devour kelp and over the past decade, 96% of the region’s kelp forests vanished. Kelp forests serve as shelter and food for a vast array of marine life and kelp sequesters carbon as much as 20 times more than terrestrial forests.

Researchers in California and Alaska are breeding sunflower sea stars in captivity to try to produce enough of the creatures to support reintroduction. The first successful spawning of sea stars took place last year at the Birch Aquarium at San Diego’s Scripps Institution of Oceanography. But all of these are siblings, which is not a desirable breeding stock for a new population. So, they are now working with the Alaska SeaLife Center, which has the largest collection of the animals in the world. The center will provide animals to introduce genetic diversity to the growing population in captivity.

The hope is to be able to reintroduce sea stars to the Pacific region within three to five years.

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A rare, giant starfish could hold the key to restoring kelp forests on the California coast

Photo, posted November 11, 2007, courtesy of Patrick Briggs via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Elephants have names

July 11, 2024 By EarthWise Leave a Comment

Elephants are considered to be very smart creatures. They have the largest brain of any land animal and have three times as many neurons as humans. Of course, a lot of that brain hardware is needed to control those big elephant bodies, but elephants have also demonstrated impressive mental capabilities on many occasions.

A new study by an international team headed by researchers from Colorado State University has found that elephants call each other by name and respond when they hear others call their name.

The researchers analyzed hundreds of elephant calls recorded over more than a year in Kenya. With machine learning techniques, they were able to identify specific sounds that elephants made when calling each other. When the researchers played recordings of these sounds, the elephants responded to the sound of their own name by calling back or moving toward the loudspeaker. Their response to other names was much less enthusiastic.

Very few animals use names at all, and, in most cases, it is more a matter of imitation. For example, dolphins refer to other dolphins by mimicking their unique sounds.

These findings at least suggest that elephants may be capable of abstract thought and perhaps may have a vocabulary beyond names for each other. The researchers are investigating whether elephants can identify food, water, or locations using their calls. The great hope is that it might ultimately be possible to communicate with elephants directly. It would be wonderful to be able to alert them to poachers or other threats. The lead author of the study said that he would like to be able to tell elephants things like “Do not come here. You’re going to be killed if you come here.”

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Elephants Have Names for Each Other, Study Finds

Photo, posted April 24, 2016, courtesy of Neil Ransom via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Hope for white rhinos

February 28, 2024 By EarthWise Leave a Comment

There are only two northern white rhinos left in the world, and both of them are female. The last male died in 2018. Northern white rhinos live to about 40 and one of the two remaining is 35 and the other 24. The clock is ticking for the species.

Recently, scientists with the BioRescue consortium successfully used in vitro fertilization to impregnate a southern white rhino. It was the world’s first IVF rhino pregnancy.

There is now some hope that IVF could be used to produce more northern white rhinos. For various medical reasons, neither of the remaining two female rhinos can serve as a surrogate mother. But there is a plan B.

For a number of years, BioRescue has been creating northern white rhino embryos with eggs from the remaining females and sperm that was collected from males before they died. There are now 30 northern white rhino embryos in cold storage, and they are continuing to produce more.

The recent success with the southern white rhino IVF provides hope that southern white rhino females can act as surrogate mothers with implanted northern white rhino embryos. The species are similar enough that it should work.

The plan is to select surrogates and implant them. This should happen this year. A rhino pregnancy lasts 16 months. If this is successful, there could be northern white rhino babies in two or three years. The scientists want the offspring to live with the surviving northern whites for years to learn the social behavior of its kind.

It is possible that these gentle, hulking creatures may get a new lease on life.

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Just two northern white rhinos are left on Earth. A new breakthrough offers hope

Photo, posted September 16, 2017, courtesy of San Diego Zoo Safari Park via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Whales Eating Plastic | Earth Wise

December 1, 2022 By EarthWise Leave a Comment

Plastic waste has been accumulating in the world’s oceans in greater and greater quantities and much of it is in the form of microplastic particles. Many kinds of whales – the largest creatures on Earth – feed by gulping up mouthfuls of krill and other tiny creatures and then straining the seawater through bristly filter structures called baleens. As they do this, they are likely to be swallowing large amounts of plastic.

Scientists at Stanford University recently estimated just how much plastic whales are ingesting by tracking the foraging behavior of 65 humpback whales, 29 fin whales, and 126 blue whales in the Pacific Ocean. Each of the whales was tagged with a camera, microphone, and GPS device suction-cupped to their back.

After accounting for the concentration of microplastics in parts of the Pacific Ocean, the researchers were able to estimate the amount of plastic the whales were consuming. Humpback whales likely consume 4 million microplastic pieces each day, adding up to about 38 pounds of plastic waste. Fin whales swallow an estimated 6 million pieces each – amounting to 57 pounds of plastic. Blue whales, which are the largest creatures on Earth, eat an estimated 10 million microplastic pieces, or as much as 95 pounds of plastic waste each day.

Despite their enormous size, whales actually eat rather low on the food chain, which puts them close to where the plastic is in the water. Krill eats plastic and whales eat the krill. Many marine animals are at risk of eating microplastics, but whales are unique in that they can consume so much of it. It is just one more way in which the ocean plastic situation is a global crisis.

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Blue Whales Swallowing 95 Pounds of Plastic Daily, Scientists Estimate

Photo, posted October 21, 2005, courtesy of Tobias Begemann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Life In The Great Pacific Garbage Patch | Earth Wise

June 14, 2022 By EarthWise Leave a Comment

The world’s oceans contain five gyres, which are large systems of circular currents created by global wind patterns and the Earth’s rotation. Gyres act like gigantic whirlpools. Anything that floats into one of them eventually ends up in the center. Ever since floating plastic waste started entering the ocean, it has poured into these gyres and created so-called garbage patches. The largest of these is the Great Pacific Garbage Patch, located halfway between Hawaii and California. According to the Ocean Cleanup Foundation, the Great Pacific Patch contains at least 79,000 tons of plastic.

A recent study has shown that the garbage patch is not just a place where drifting plastics aggregate; it is also a place where drifting animals aggregate.

It turns out that the Great Pacific Garbage Patch is absolutely teeming with life, primarily small surface-dwelling animals that are collectively known as neuston. A ship surveying the garbage patch found that in some places, there were nearly as many neuston as there are pieces of plastic.

Typical creatures in the patch are blue dragon nudibranchs, Portuguese man-o-wars, anemones, sea snails, blue buttons (which are related to jellyfish) and hydrozoans. It appears that these creatures are reproducing within the garbage patch. Little is actually known about the life history and ecology of these creatures, so that studying the garbage patch is offering valuable insights to scientists.

Two nonprofit organizations are working to remove floating plastic from the Great Pacific Garbage Patch. Evidently, removing this existing pollution from the ocean is likely to have unexpected effects on the local ecosystem and is a source of at least some controversy. One thing that isn’t controversial, however, is that we need to stop the flow of plastic into the ocean.

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The Ocean’s Biggest Garbage Pile Is Full of Floating Life

Photo, posted in April, 2012, courtesy of Steven Guerrisi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Artificial Aquatic Polyps | Earth Wise

September 16, 2020 By EarthWise Leave a Comment

Corals are often mistaken for rocks because of their hardened surfaces. And, since they attach or “take root” to the sea floor, they are often mistaken for plants. But unlike rocks, corals are alive. And unlike plants, corals do not make their own food. Corals are actually animals.

Most of these structures that we call “coral” are made up of hundreds to thousands of tiny coral creatures called polyps. A coral polyp, which is often no thicker than a nickel, has a saclike body and mouth that is encircled by stinging tentacles. Polyps are responsible for a host of ecosystem services, including nourishing corals, and aiding coral survival by generating self-made currents through the motion of their soft bodies.

Inspired by these marine organisms, researchers from the University of Warwick in the UK and Eindhoven University of Technology in the Netherlands have collaborated to develop an artificial aquatic polyp capable of removing contaminants from water. The 1 square centimeter wireless robot polyp can attract, grasp, and release objects, moving under the influence of a magnetic field and whose “tentacles” are triggered by light.

The next step for the researchers is to see if the technology can be successfully scaled up from laboratory to pilot scale. In order for that to happen, the team has to design an array of artificial polyps capable of working harmoniously together.

Corals are an incredibly important part of ocean ecosystems. And while it remains to be seen how much value artificial polyps can achieve in future applications, it serves as another example of scientists emulating nature to create more sustainable designs.

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Aquatic robots can remove contaminant particles from water

An artificial aquatic polyp that wirelessly attracts, grasps, and releases objects

Photo, posted April 14, 2011, courtesy of Derek Keats via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Decline Of Earth’s Largest Freshwater Creatures

September 23, 2019 By EarthWise Leave a Comment

While nearly 70% of the globe is covered by water, only 2.5% of it is freshwater. The rest is saline and ocean-based. And only 1% of our freshwater is easily accessible, with much of it locked away in snowfields and glaciers.

Despite freshwater only making up a small fraction of all water on the planet, it’s home to one third of all vertebrate species. Some have survived hundreds of millions of years, but many of the world’s largest freshwater creatures – including fish, reptiles, amphibians, and mammals – may soon find themselves on the brink of extinction.

According to a study recently published in the journal Global Change Biology, scientists from the Leibniz-Institute of Freshwater Ecology and Inland Fisheries and international colleagues have quantified the global decline of freshwater megafauna for the first time. In four decades since 1970, the global populations of these freshwater giants have declined 88% – twice as much as the loss of vertebrate populations on land or in the oceans.

Freshwater megafauna include all freshwater animals that weigh 30 kilograms (about 66 pounds) or more, such as certain dolphins, beavers, crocodiles, turtles and sturgeons.

Overexploitation is one of the main threats to freshwater megafauna. (These animals are often targeted for their meat, eggs, and skin). The other main threat is the loss of free-flowing rivers. Many of the world’s large rivers are already highly fragmented, which impacts access to spawning and feeding grounds. The research team says another 3700 large dams are planned or under construction, including 800 in habitats rich with freshwater megafauna, including the Amazon, Congo, and Ganges river basins.

Current conservation measures are clearly failing our freshwater creatures.

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88 percent decline of big freshwater animals

Earth’s largest freshwater creatures at risk of extinction

Photo, posted March 25, 2012, courtesy of the U.S. Fish and Wildlife Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.