Postnatal development of diving physiology: A review to examine vulnerability of immature beaked whales to hypoxia, hypercarbia, acidosis and decompression sickness (DCS) during their flight response
Abstract
Under normal circumstances, the exceptionally long and deep dives of beaked whale species do not pose a risk for these animals because of anatomical, physiological, and behavioral adaptations. However, recently there have been multi-species mass strandings of marine mammals that were coincident with naval sonar exercises, which included beaked whale species exhibiting decompression sickness (DCS) like symptoms. The mechanism behind this pathology is still unclear. Moreover, immature beaked whales are undoubtedly the most at risk of suffering from DCS because their small body size theoretically results in higher mass-specific oxygen utilization rates compared to larger conspecifics. While at the same time, the physiology that supports breath-hold diving and submerged swimming may require postnatal development, as has been shown in other cetaceans. Because little is known about the magnitude or duration of postnatal development required to achieve mature diving physiology in beaked whale species, a review of the postnatal development in other marine mammal species will be undertaken. The magnitude and duration of the postnatal development of all aspects of the oxygen pathway will be reviewed across species in relation to maternal dependency period, habitat, and diving behavior to predict postnatal development patterns for beaked whale species. This review provides a cornerstone to ascertain the propensity of immature beaked whales to suffer from hypoxia, hypercarbia, acidosis and DCS when engaged in a "flight response" associated with exposure to anthropogenic noise. This research supports the number one priority identified in Table 1 Overview of Highest Priority Research Recommendation in Southall (2009), which is to improve the ability to understand biologically-significant effects to sound exposure.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 04, 2018
- Source ID
- N000141812789
Entities
People
- Shawn R Noren
Organizations
- Office of Naval Research
- United States Navy
- University of California, Santa Cruz