Like us, whales sing. But unlike us, their songs can travel hundreds of miles underwater. Those songs potentially help them find a partner, communicate and migrate around the world. But what if we could use these songs and machine learning to better protect them?
Despite decades of being protected against whaling, 15 species of whales A spectrogram (visual representation of the sound) of a humpback whale song in Hawaii.
We decided to leverage Google’s existing work on large-scale sound classification and train a humpback whale classifier on NOAA’s partially annotated underwater data set. We started by turning the underwater audio data into a visual representation of the sound called a spectrogram, and then showed our algorithm many example spectrograms that were labeled with the correct species name. The more examples we can show it, the better our algorithm gets at automatically identifying those sounds. For a deeper dive (ahem) into the techniques we used, check out our Google AI blog post. To find out how this project was started, read the NOAA Fisheries blog post by Research Oceanographer Ann Allen.
Now that we can find and identify humpback whales in recordings, it allows us to understand where they are and where they are going—as shown by the animation below.
Since 2005, NOAA’s Pacific Islands Fisheries Science Center has deployed, recovered and collected recordings from hydrophones moored on the ocean bottom at 12 sites. On this map, you can see the spots where more whales were found by our classifier in orange and yellow.
In the future, we plan to use our classifier to help NOAA better understand humpback whales by identifying changes in breeding location or migration paths, changes in relative abundance (which can be related to human activity), changes in song over the years and differences in song between populations. This could also help directly protect whales by advising vessels to modify their routes when a lot of whales are present in a certain area. Such work is already being done for right whales, which are easier to monitor because of their relatively simple sounds.
The ocean is big and humpback whales are not the only ones to make noise, so we also started training our classifier on more species sounds (like the southern resident killer whale, which is critically endangered). We can’t see the species that live underwater, but we can hear a lot of them. With the help of machine learning, we hope that one day we can detect and classify a lot of these species sounds, giving biologists around the world the information needed to better understand and protect them.
A humpback whale breaching at the surface of the water. (Photo credit: Hawaiian Islands Humpback Whale National Marine Sanctuary.)
Source : A tale of a whale song
