Thar She Blows! A Novel Method for DNA Collection from Cetacean Blow

Abstract

BackgroundMolecular tools are now widely used to address crucial management and conservation questions. To date, dart biopsying has been the most commonly used method for collecting genetic data from cetaceans; however, this method has some drawbacks. Dart biopsying is considered inappropriate for young animals and has recently come under scrutiny from ethical boards, conservationists, and the general public. Thus, identifying alternative genetic collection techniques for cetaceans remains a priority, especially for internationally protected species.Methodology/Principal FindingsIn this study, we investigated whether blow-sampling, which involves collecting exhalations from the blowholes of cetaceans, could be developed as a new less invasive method for DNA collection. Our current methodology was developed using six bottlenose dolphins, Tursiops truncatus, housed at the National Aquarium, Baltimore (USA), from which we were able to collect both blow and blood samples. For all six individuals, we found that their mitochondrial and microsatellite DNA profile taken from blow, matched their corresponding mitochondrial and microsatellite DNA profile collected from blood. This indicates that blow-sampling is a viable alternative method for DNA collection.Conclusion/SignificanceIn this study, we show that blow-sampling provides a viable and less invasive method for collection of genetic data, even for small cetaceans. In contrast to dart biopsying, the advantage of this method is that it capitalizes on the natural breathing behaviour of dolphins and can be applied to even very young dolphins. Both biopsy and blow-sampling require close proximity of the boat, but blow-sampling can be achieved when dolphins voluntarily bow-ride and involves no harmful contact.

Genetics and the conservation of natural populations: allozymes to genomes

“…; Frère et al . ). Thus, there were now no limitations in describing genetic variation in any species of interest.…”

The marine mammal microbiome: current knowledge and future directions

“…In order to increase existing data on the marine mammal microbiome, logistically feasible, nonor minimally-invasive sampling protocols that are easily reproducible and provide biological material suitable for a range of studies are necessary. For example, respiratory blow can be used to examine host DNA 42 and hormone levels 43,44 as well as respiratory associated microorganisms 19,33,37 , while non-invasively collected fecal samples can be used to study host DNA 45 , prey items 46 and the gut microbiome 22,23 .…”

Short-term reactions and long-term responses of bottlenose dolphins (Tursiops truncatus) to remote biopsy sampling

“…Recently, DNA has been successfully extracted from the blow of wild whales and dolphins kept in captivity (Fre`re et al 2010); however, the efficiency of this method has yet to be adequately tested in wild small cetacean populations.…”