This Center-funded project was conducted by the Johns Hopkins University, under the direction of Dr. Joseph Katz and Subhamoy Gupta (2021-2025). With appreciation for the support from the National Aquarium (Baltimore, MD) staff and their dolphins.
Project Investigators:
- Dr. Joseph Katz, Johns Hopkins University, Department of Mechanical Engineering
- Subhamoy Gupta, Graduate Research Assistant, Mechanical Engineering, Whiting School of Engineering, Johns Hopkins University
- Yulong Liang, Graduate Research Assistant, Mechanical Engineering, Johns Hopkins University
Project Oversight Committee:
- Nancy Kinner, Coastal Response Research Center, UNH
- Lisa DiPinto, NOAA OR&R
- Daniel Levine, NOAA Fisheries Southeast Regional Office, Protected Resources Division
- Eric Vichich, NOAA Fisheries, Office of Habitat Conservation, Restoration Center
- Rebeccah Hazelkorn, NOAA Fisheries Southeast Regional Office, Protected Resources Division
- George Graettinger, NOAA OR&R
- Teri Rowles, Elizabeth Stratton, Sarah Wilkin, NOAA Fisheries
- Adriana Bejarano, NOAA OR&R ERD
Project Overview for Phase 1A (Baltimore Aquarium trained dolphins):
The National Oceanic and Atmospheric Administration (NOAA) Office of Response and Restoration (ORR) in collaboration with the Coastal Response Research Center, NOAA Fisheries, the Baltimore National Aquarium and Johns Hopkins University has developed a project to advance understanding of surface oil exposure to marine mammals during and following an oil spill, including surface dispersant application scenarios. The first part of this multi-phased project focused on characterizing droplet formation, size, and behavior during surface breathing events (exhalation and inhalation) from bottlenose dolphins (Tursiops truncatus), without oil. The ultimate goal of this study is to create a better understanding of the behavior of oil and water droplets during a dolphin breathing event and form an overall picture of exposure and risk posed to those animals after an oil spill.
dolphin blowhole at Baltimore Aquarium
The scope of this phase is to characterize dolphin exhalation induced water droplet production, and to measure inhalation and aspiration plume velocity and liquid volume fraction during different near-surface respiration events. Measurements were performed from bottlenose dolphins in a managed care facility using three different breath event types e.g., normal, chuff and post-exercise. Some of the breath type measurements were replicated for the same individual. Data was collected for a total of 94 breathing events from the six dolphins of different sex and size. Of these breathing events, 26 events have been analyzed and are being presented in this report.
See Final Report for Phase 1A here>>
See Video here>> Training dolphin at Baltimore (MD) Aquarium while collecting blowhole spray data video here>>
Project Overview for Phase 1B.i - Design, Construction, and Validation of Laboratory Apparatus to Mimic Exhalation and Inhalation of Oily Aerosols by Dolphins
laboratory experimental design
The objective of this laboratory study is to determine quantitatively the spatio-temporal distributions of oily aerosols generated above oil slicks and possibly inhaled or aspirated by processes mimicking the breathing (exhalation/inhalation) of dolphins. The experiments will involve generation of transient vertical air jets from a source located just below or above the surface of seawater containing crude oil slicks, followed by suction into an internal chamber. The size, duration, speed, and time history of the air jet will replicate the exhalation breathing phase of live dolphins, as measured recently in the National Aquarium in Baltimore during phase 1A of this project. However, the scales and range of speeds will extend beyond the specific measured values to account for the possibility that wild dolphins might have a broader range of breathing conditions or blowhole size. This range will be selected based on discussions with the NOAA partners and reviewing the relevant literature and actual breathing events in wild dolphins, as will be specified in the proposal submitted for Phase 1B.ii. The tests involving live dolphins consisted of application of high speed cinematic holography for measuring the spatio-temporal size distributions of seawater spray (obviously without oil) in a captive environment generated by 4 female and 2 male dolphins that had been trained to breathe within the field of view of the instrument package. In some of the tests, the sample volume was also seeded with water mist. These aerosols simulated the presence of ambient aerosols in oceanic conditions, and enabled us to obtain a more complete database on the time history of air flow during the inhalation and exhalation phases of a breathing event.
Phase 1B.ii: Measurements of Exhalation and Inhalation of Oily Aerosols in a Laboratory Apparatus Mimicking the Breathing of Dolphins
This statement of work corresponds to Phase 1Bii of a project aimed at characterizing the generation of oily aerosols and resulting inhalation of oil and water by breathing of bottlenose dolphins near oil slicks. During an earlier phase (1A) of this project we measured the speed and spatio-temporal distributions of airborne water droplets generated by dolphins in the National Aquarium in Baltimore. These experiments involved application of high speed cinematic holography to measure the size, trajectory, and speed of seawater droplets generated above the blowholes of live female and male dolphins trained to breath within the field of view of the instrumentation package. The results have been described in a recently submitted final report, and a corresponding publication that is presently under preparation. Comparisons to published field and captivity data indicate that the range of total exhalation and inhalation air volumes as well as the maximum air flow rates of the aquarium dolphins are consistent with those of the field measurements, suggesting that the acquired data is relevant to dolphins in the wild. In addition to volumes and flow rates, the report provides statistics on: (i) the time history of seawater droplet size and spatial distributions during exhalation and inhalation, hence the entire volume of exhaled and inhaled aerosols, (ii) the size, duration, and velocity time history of the transient air jet generated by the dolphins’ exhalation for several types of breath, including normal breathing, and post-exercise breathing.
