The mysterious and elusive Cuvier's beaked whale has been crowned as the best deep diver in the world amongst mammals. Aside from diving deep into the ocean, these whales can also hold their breaths for a remarkable length of time.

While scientists have recorded the diving behavior of these whales for a while now, a newly completed long-term study has finally revealed the real ability of the Cuvier's beaked whale. The results were both unexpected and surprising.

"Cuvier's beaked whales (Ziphius cavirostris) are known as extreme divers, though behavioral data from this difficult-to-study species have been limited," says the study. "They are also the species most often stranded in association with Mid-Frequency Active (MFA) sonar use, a relationship that remains poorly understood."

Among the whales observed by the researchers, one particular individual was able to dive to a depth of 9,816 feet during a 138 minute dive. These results show that the Cuvier's beaked whale is one of the most adept diving mammals in the wild. 

The study was conducted by a team of researchers and the U.S. Navy and the results were published in the online journal PLOS ONE.

"We used satellite-linked tags to record the diving behavior and locations of eight Ziphius off the Southern California coast for periods up to three months," the study says. "The effort resulted in 3732 hr of dive data with associated regional movements - the first dataset of its kind for any beaked whale - and included dives to 2992 m depth and lasting 137.5 min, both new mammalian dive records."

Since Cuvier's beaked whales often spend time in the depths of the oceans far from land, gathering data about their behavior can be very difficult. Moreover, these whales have a very timid nature and they rarely approach boats. The few specimens of these whales that have been studied consisted of beached whales that ended up on beaches in the Bahamas, the Canary Islands and the Mediterranean. Due to the unusual sonar activity that may contribute to the beaching of these whales, the U.S. Navy also helped out with the study.

Due to the difficulty of gathering data about Cuvier's beaked whales, data sets collected over a long period of time were previously unavailable until the current study was completed.

The study that has used better data sets push aside conclusions made by earlier studies that relied on data collected on a shorter period of tme.