People who join shark ecotourism tours are more likely to take action to protect sharks, including donating to related causes, signing petitions, or speaking up online, new research from the University of Sydney shows. 

Sharks can hear – and react to – underwater sounds from nearly 250 feet away, according to a new study that provides the first quantified evidence of long-distance sound detection in free-swimming sharks. Researchers found that blacktip sharks rapidly changed course when they detected low-frequency sounds, revealing that they not only hear distant sounds but also determine where they are coming from. The findings also show sharks are more sensitive to lower-frequency sounds, providing new insight into how these ancient predators sense their underwater world.

Tiny plantlike organisms called phytoplankton that form the base of marine food webs topped by orcas, whales, and sharks usually get eaten or slowly sink to the seafloor, carrying carbon as they go. 

Across most of the ocean, the descent from sunlit surface layers takes weeks. But in the Arctic’s Chukchi Sea, scientists have found that a convergence of currents pushes phytoplankton from under the ice to the seafloor at four times the usual speed. 

Two new papers led by researchers in the lab of Stanford biological oceanographer Kevin Arrigo detail this unusual descent and reveal that blooms of phytoplankton, which use energy from the sun to grow, can be 10 times denser in the darker waters below thick sea ice than out in the open water.

While the Discovery Channel's annual shark week event has given the public more familiarity with the species, there is much about sharks—from their mysterious love lives to how their eating habits bring them into conflict with recreational anglers—that remains a mystery to scientists. Now, two new studies led by researchers from the University of Massachusetts Amherst peer into these important aspects of shark biology to help guide real-world conservation strategies.

Fossil shark scales from Panama’s Caribbean and Pacific coasts show that the two seas never held the same number of sharks, and that borrowing a conservation target from one ocean could be wrong by an order of magnitude.