First Long-Term Behavioral Records from Cuvier’s Beaked Whales (Ziphius cavirostris) Reveal Record-Breaking Dives

Abstract

Cuvier’s beaked whales (Ziphius cavirostris) are known as extreme divers, though behavioral data from this difficult-to-study species have been limited. They are also the species most often stranded in association with Mid-Frequency Active (MFA) sonar use, a relationship that remains poorly understood. 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 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. Deep dives had a group mean depth of 1401 m (s.d. = 137.8, n = 1142) and duration of 67.4 min (s.d. = 6.9). The group mean time between deep dives was 102.3 min (s.d. = 30.8, n = 783). While the previously described stereotypic pattern of deep and shallow dives was apparent, there was considerable inter- and intra-individual variability in most parameters. There was significant diel behavioral variation, including increased time near the surface and decreased shallow diving at night. However, maximum depth and the proportion of time spent on deep dives (presumed foraging), varied little from day to night. Surprisingly, tagged whales were present within an MFA sonar training range for 38% of days locations were received, and though comprehensive records of sonar use during tag deployments were not available, we discuss the effects frequent acoustic disturbance may have had on the observed behaviors. These data better characterize the true behavioral range of this species, and suggest caution should be exercised when drawing conclusions about behavior using short-term datasets.

Description of the skeleton of the fossil beaked whale <i>Messapicetus gregarius</i>: searching potential proxies for deep-diving abilities

“…The best-known modern ziphiids perform regular dives to reach foraging grounds up to 3000 m, beyond the photic zone, where they capture cephalopods, crustaceans, and bathypelagic fish via suction (Clarke, 1996;Heyning and Mead, 1996;Hooker and Baird, 1999;Johnson et al, 2004;MacLeod et al, 2003;Minamikawa et al, 2007;Schorr et al, 2014;. Accordingly, Ziphiidae share a unique set of morphological, physiological, and behavioural adaptations allowing them to optimize the travel time to reach their foraging grounds.…”

No deep diving: evidence of predation on epipelagic fish for a stem beaked whale from the Late Miocene of Peru

“…First, data on extant ziphiids (stomach contents, satellite recordings of dives, and geographical distribution in relation to sea floor topography; e.g. [2,4,7]) indicate that it is more parsimonious to characterize the last common ancestor of all modern ziphiids as adapted to deep dives. Second, most stem ziphiids were found in platform deposits, contrasting with the discovery of many fossil crown ziphiid remains in deep-sea deposits [6,[8][9][10][11].…”

Bucking the trend: genetic analysis reveals high diversity, large population size and low differentiation in a deep ocean cetacean

“…Tagging data from Blainville's beaked whales (Mesoplodon densirostris) have revealed a relationship between foraging behaviour and oceanographic features, for example, water depth, movements of the deep scattering layer of mesopelagic prey and seabed topography (Johnson et al, 2008). Indeed, tagging data suggest that Cuvier's beaked whales perform the deepest dives of all mammals, almost 3000 m (Schorr et al, 2014). Furthermore, modelling implies that beaked whales require larger, higher quality habitats than other cetaceans to meet the energetic needs of such deep diving (Wright et al, 2011;New et al, 2013).…”