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Deep Voice Foundation
Deep Voice – The Israeli Foundation for Whales Communication Research

Mozambique Humpback Whales Acoustics Correlated with Observed Behavior Research


An Israeli research team with the aim of studying humpback whales behavior has been formed. The goal of the team is to correlate humpback whales observed behavior with their emitted acoustic signals. The group conducted one successful research expedition for recording and data acquisition, and intends to continue the research in order to give a glimpse into the fascinating world of whale communication.


Humpback Whales within the southwestern Indian Ocean undertake annual migrations from summer in Antarctic/Southern Ocean feeding grounds into winter breeding grounds in the tropical and sub-tropical coastal waters of Mozambique, classified as the C1 Breeding Stocks.
Humpback Whales Megaptera novaeangliae are acoustically oriented. Baleen whales are well known for complex vocal behaviors that are seasonally and geographically stratified. Therefore, humpback whales are of great interest for marine mammals acoustic correlated behavior research.
The C1 Breeding Stock has never been acoustically researched before.


The research consists of two intertwined phases: Data acquisition and data analysis. The skills required for the data acquisition phase are underwater video photography of Humpback Whales behavior and acoustic data acquisition using hydrophones.
The data analysis phase utilizes state-of-the-art methods for signal processing, essential for understanding the whale's behavior Ethogram and we hope that it will also lead to communication per se.
The first research expedition was conducted in at the Bazaruto Center for Scientific Studies, located at Bazaruto Archipelago in Mozambique. The group spent 23 days at the BCSS, with 13 days of field recordings. More than 5 hours of recordings and photos of dozens of individuals were collected.


The research and engineering group developed a unique acoustic toolbox for data analysis that will be published to aid the entire bio-acoustical community worldwide, as an open-source code.
The analysis of the recorded signals & behavior that is collected would reveal a new insight on Humpback Whales Underwater behavior categories & first understanding of the communication of C1 group. Such information might be essential for whale's conservation and study attempts in the future.
The research was filmed and documented and is expected to get media exposure.

Future Goals:

Collecting more data of Humpback Whales communication, especially the mother-calf communication.
Publishing a paper about the research conclusions and developed tools and algorithms.
Expanding the group's scientific span to more core bio-acoustical problems regarding Whales and Cetaceans communication.

We are currently looking to expand our foundation and are always happy to hear from researchers, marine-mammal enthusiasts and media experts. 
If you support our cause, your donation would make a difference.

About us

Michael Michelachvili (2013) BSc – Graduate Student at Tel Aviv University, main research interests are signal processing and deep learning. Retired captain from the Israeli Air Force that was part of the acoustic signature team. Developed computational simulations and physical models of acoustic wave propagation, psychoacoustics and conducted acoustical experiments. Graduated B.Sc. degree in Chemistry (Summa Cum Laude) while studying in high-school. Participated and awarded three times in the International Chemistry Olympiad. Utilizing multidisciplinary approach to solve problems in research and engineering. 

Michael Faran (2013) BSc - Israeli Air Force acoustic signature team leader. A former cadet of Psagot, the Israeli Defense Force elite program for academic military reserve. Studied Physics BSc and Electrical Engineering BSc in Tel- Aviv University. Winner of the annual Niv-Ya prize in 2017 , granted by the faculty of aerospace sciences of the Technion – Israel Institute of Technology .Since 2015, Michael is a MSc student  of physics in Tel Aviv University. With over four years of experience in the different acoustics fields such as psychoacoustics, atmospheric acoustics and aeroacoustics, Michael is now eager to get a foot in the door of Marine Mammal's acoustics research.

Daphna Stern (2018) B.A - Israeli photographer based in Jerusalem. She has been photographing professionally since 2011 and her photos have been inspired by her world travel and cultural experiences. Her work has been featured in several publications and exhibitions.
She graduated with a B.A. degree in Photographic Communication from the Hadassah College in Jerusalem.
Prior to attending Hadassah College, Daphna was a Padi and SSI licensed Scuba Diving Instructor. With her passion for diving, she strives to capture moments under the water through various photography projects.

Noam Bressler - Team leader in the Acoustic Countermeasure department of the Israeli Navy. A former cadet of the Talpiot program, the Israeli Defence Forces flagship program for R&D leadership. Noam studied a Physics BSc at the Hebrew University of Jerusalem, graduating in 2013. During his service at the Israeli Navy since, Noam developed and deployed algorithms in the fields of underwater acoustic wave propagation, acoustic signal processing and machine learning systems for classification of acoustic data, and planned, conducted and analyzed underwater acoustic experiments. Since 2015 he is a Graduate Student for M.Sc at the physics department in Tel-Aviv University.
As part of the team, Noam hopes to use his acquired experience in underwater acoustics to shed light on the life and communication of marine mammals.

Amit Galor – Officer at the Israeli Ministry of Defense Director of
Defense Research & Development (DDR&D) underwater acoustics
branch. Graduated from the Technion – Israel Institute of Technology,
with a B.Sc. in Electrical Engineering and in Physics. Worked as a
visiting scholar with the Laboratory for Ocean Acoustics and Ecosystem
Sensing at Northeastern University, Boston, MA. Currently studies for a
Master’s degree in Electrical Engineering at Tel Aviv University with a
specialization in signal processing and machine learning. Has 4 years of
experience in conducting experiments with acoustic systems in the underwater medium, analyzing
acoustic data and managing large scale development projects.
Press release

Between September 5 and 25, 2018, an Israeli research team set out to investigate humpback whales (​Megaptera novaeangliae)​ In Bazaruto Archipelago Located in Mozambique, southwestern Indian Ocean. The delegation studied the acoustics callings of the whales in connection with their observed behavior and the whale distribution in the archipelago. The research delegation consisted of six team members, researchers and volunteers: Dr. Oz Goffman from the University of Haifa, Michael Faran and Michael Moshe Michelashvili - graduate students and researchers from Tel Aviv University, Daphna Stern - diving instructor and documentary photographer, Anat Gold and Inbar Rachel Gold. The study area was located west of the Archipelago chain - see map of the survey routes. The whale population in the area follows an annual migration route that begins in the Antarctic Ocean and ends in the Bazaruto Archipelago. The whales arrive at the archipelago at the end of August for a period of three and a half months. The archipelago is the breeding ground of the whales, that is, a designated place where they mate, give birth and start nursing the offspring's. During the stay in the archipelago, the whales fast. The feeding areas of the whales are in the Southern Ocean, to which they return in the spring.
It was the first Israeli expedition to investigate this species of whale. The delegation departed from the Recanati Institute for Maritime Studies / School of Marine Sciences at the University of Haifa. It was headed by Dr. Oz Goffman, research fellow and director of the dolphins project, IMMRAC - ​Israel Marine Mammal Research & Assistance Center​, with the scientific support of Dr. Dani H Kerem, research fellow and the president of IMMRAC, and Junio Fabrizio Borsani from Italy. In the thirteen days of research carried out on an outboard engine catamaran boat, the researchers embarked from and returned every day to a local research institute called BCSS - Bazaruto Center for Scientific Studies, covering a cumulative track of 160 nautical miles. The study included visual documentation of the encountered animals in the area. At the same time, the research team recorded vocal calls and intonations of mother-calf pairs and sometimes of escort males who accompanied them. The mothers and calves stay mainly inshore, at a relatively shallow depth. They were documented by the researchers at depths of 8 to 80 meters, while male pods were located in deeper waters. The recordings were made using hydrophones - designated underwater microphones - with a preamplifier and recorder.
The research team recorded about 5 hours of signals from different pods, mainly in order to detect calls of social communications between mothers and calves, which were hardly studied. This, in contrast to the ‘singing’ of the males, which were and still are a subject of extensive and long-term studies by many researchers around the world.
For the synchronization of the recordings with the visual information, the study was documented by the Delphis application, a system for the collection of marine mammal survey data developed by IMMRAC. Visual documentation of the whales was made mostly by video shots above water, but also by underwater filming and still photos. The main goal of the study is to link the observed behavior of the individual to its recorded communication, thus deciphering the significance of the different communication modes of the humpback whale. This can be likened to understanding the meaning of certain words in an unfamiliar language by observing the behavior that accompanies them.
In addition to acoustic-behavioral research, the team documented, identified and photographed thousands of images in the area under investigation. Individuals in the population were identified by photo ID photographs of the pattern of pigmentation on the underside of the flukes and by the profile of their dorsal fin. About 40 individuals were photo IDed, out of dozens of whales visiting the area each year. This part of the study contributes to the conservation of the local population. In the coming months, the researchers will work on the images, videos, and five hours acoustic recordings, in cooperation with parallel research groups around the world, to extract the desired product of social calls and their observed behavioral context. In the long term, using the results of the research, research and engineering tools will be designed to improve whale recordings throughout the globe.
The study also documented three other marine mammal species:
Dugong dugon - an endangered herbivorous​ ​marine​ mammal​, ​one of four living species of the order Sirenia
Spinner dolphin - Stenella longirostris
Indo-Pacific humpback dolphin - Sousa plumbea
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