The black-legged kittiwake is know for its rhythmic calls. The gull is abundant in the Bering Sea, and, in winter, can also be found along the east and west coasts of North America. Michael Stein has this BirdNote®.

Scientists have discovered the first known examples of hybrid sharks, the result of interbreeding between Australian blacktip and common blacktip sharks. As Living on Earth’s Mary Bates reports, the hybrids appear to be thriving in Australian waters and span multiple generations.

Concrete is one of the most widely used materials in the world. It also accounts for five percent of the world’s carbon dioxide emissions. But researchers at Drexel University are trying to change that with a cool new cement that doesn’t need heating, just mixing. Drexel engineering professor Alex Moseson sat down with host Bruce Gellerman to tell us more about the process.

Scientists studying H5N1, or the bird flu, recently discovered something big: a strain of the virus that can spread through the air between animals. Dr. Michael Olsterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, tells host Bruce Gellerman why his concerns for biosafety and security led him to recommend limiting the publication of this new research.

Biofuel production could be a boon for the environment, but there’s still a lot of waste plant material, called lignin, remaining from the process. Now, an enterprising student has found a new use for some of that waste – paving unpaved roads. Host Bruce Gellerman speaks with Wilson Smith of Kansas State.

Mozambique is among the African countries most vulnerable to extreme weather events. Cyclones, droughts, and floods have destroyed homes and crops. The organization Save the Children has partnered with the government to promote programs aimed at making the local economy less contingent on the weather. Rowan Moore Gerety reports from Caia, Mozambique.

Many environmentalists applauded when President Obama rejected the Keystone XL pipeline plans. But Kansas writer Julene Bair wants to know why it took a major pipeline to draw attention to the crucial Ogallalla aquifer. She asks whether that attention will last, or dry up as quickly as it materialized.

Musk oxen are hearty creatures, capable of enduring the long, dark winter. But as Ari Daniel Shapiro reports, when temperatures rise, that heartiness can wane.

President Obama says the United States is going to develop all forms of domestic energy, focusing on natural gas and clean renewables. But what he didn’t talk about in his State of the Union speech is equally interesting. Host Bruce Gellerman talks to New York Times blogger Andy Revkin and Reason Magazine science writer Ron Bailey about the president’s address.