RATE · Respiratory Acoustics To estimate Energy in wild cetaceans
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2017-02-01 → 2019-01-31
- EU contribution
- €200,195
- Participants
- 1
- Scheme
- MSCA-IF-EF-ST
Lines connect the coordinator with its partners.
Results in brief
RATE: Respiratory Acoustics To estimate Energy in wild cetaceans
Respiratory rate is a vital sign often used to assess responses to natural and disturbed behavior in humans and in animals, but how much air do they exchange with every breath? Cetaceans (whales and dolphins) show considerable variation in tidal volume, the volume of air breathed in and out. This greatly affects estimates of metabolic rate from breathing frequency alone, especially in the short-term or during activity. Monitoring tidal volume in wild animals is challenging, especially in cetaceans. We sought to estimate free-ranging tidal volumes by applying techniques from human medicine to establish a relationship between recorded respiratory sounds and measured air-flow rates. Through RATE, we have made the first near-continuous breath-by-breath estimates of tidal volume in wild cetaceans, with major implications on estimating short-term ventilation and gas exchange in natural and disturbed behaviors. Objectives I: Estimate respiratory flow rates from breath sounds recorded in bottlenose dolphins, calibrated to measurements. II: Apply the method to monitor free-ranging tidal volumes of tagged wild dolphins. III: Assess changes in respiratory variables in response to specific exposures or behaviors measured by tag inertial and acoustic sensors.
Data: CORDIS, © European Union
Project objective
Cetaceans are apex predators with significant top-down roles in the marine ecosystem. The impact of these roles must be quantified by measuring energetics in the wild, which has proven difficult in cryptic, highly mobile animals. Current techniques to estimate energy use in free-swimming dolphins overestimate measured values by >200% or integrate energy expenditure over time scales too long to detect responses to specific events or conditions. Through RATE, I will make the first reliable estimates of energy expenditure in managed and free-swimming cetaceans by applying novel techniques from human medicine to extract information from respiratory sounds. RATE will (I) calibrate respiratory flow rates from breath sounds recorded in bottlenose dolphins, (II) apply this calibration to tag deployments on free-swimming, wild dolphins to derive reliable estimates of airflow and energy use, and (III) assess changes in respiratory condition in response to specific events or behaviours. RATE’s objectives require simultaneous respiratory measurements and acoustic recordings of each breath: a custom-built pneumotach placed over the blowhole of bottlenose dolphins will record respiratory flow rates and gases, while state-of-the-art acoustic tags (DTAGs) placed near the animal’s blowhole with suction cups concurrently record the sound of exhalation and inhalation. In accomplishing RATE’s Objectives, I will provide a quantitative and mechanistic framework to define the cost of existence of cetaceans in their natural habitats – a major breakthrough in marine mammal physiology that is directly relevant to the European Commission (EC)’s Marine Strategy Framework Directive. The novel methods I will develop for RATE will overcome existing limitations of measuring field metabolic rates in free-swimming animals, and will increase the resolution of field metabolic rate from days to seconds to revolutionize how we measure energy turnover of marine mammals in the wild.
Original text from CORDIS.
Participants
- AARHUS UNIVERSITET · Aarhus CCoordinatorDenmark
Links
- View on CORDIS
- DOI: 10.3030/706867
- https://marinebioacoustics.wordpress.com/people/julie-van-der-hoop/
Data: CORDIS, © European Union