Counting sharks on Palmyra Atoll

A new paper just came out using dual-frequency identification sonar to track sharks as they enter and exit the Palmyra lagoon using the channel cut through the reef by the U.S. Navy during World War II. While only one of the authors, Fio Micheli, is currently from Hopkins Marine Station, three of the other four authors who are from UC Santa Barbara have a history with Hopkins and Stanford as students working on Palmyra.

Using military sonar technology, the group was able to document the movement of sharks as they passed through the channel. Over the 443 recorded hours they observed 1,196 sharks with a maximum of 10 sharks appearing in a single frame. There seems to be a shark "rush hour" at dusk with the shark traffic peaking between 7 and 8 pm.

Below are two links with more details about this scientific paper.

http://www.news.ucsb.edu/2016/016952/rush-hour-palmyra-atoll

http://www.livescience.com/55091-sharks-evening-rush-hour-discovered.html

blacktip sharks are the most common species observed in the Palmyra lagoons
Carcharhinus limbatus