7 — Underwater components of humpback whale bubble-net feeding behaviour

Bubble-net feeding is the coolest.

In short: Humpback whales blow a wide cylinder of bubbles around schools of fish to trap them — and then dive below the “net” in order to rise up inside it and gobble up the good eats.

What’s so interesting to me is that multiple whales coordinate their movements in a deterministic way to engage in this behavior. This paper was the first time a study co-registered 3D underwater motion data with sound data.

The paper mentions two main varieties of bubble net; an upward-spiral and a double-loop. It also mentions that not all whales participated in the bubble blowing, though they did get the free meal. With my very basic understanding of marine biology — I wonder if this means that bubble net feeding is a taught behavior and not innate, where the variations suggest different teachers. I also wonder if the “silent” whale is a student (or is just learning while stealing some food). Humpback whales usually do not stay with their family throughout life, according to the paper, which makes me wonder if this feeding behavior is passed down like human oral tradition (i.e. not necessarily through kin lineage).

This study predominantly focused on using the recordings to determine when the whales were emitting bubbles, but I would be very interested to look at the audio data for potential “coordinating” communication as well. It seems to me that the types of calls or the content of the calls should in some way correlate with the behavior of the whales in the feeding pattern.

The spatial data does not include speed information, and so the authors assumed a constant speed for the duration of the recordings. The seems like a pretty severe but inescapable shortcoming to me, but it also (in my imagination) conveniently points directly to the paper I read yesterday on how to reconcile location information in partially informed, low-resource sensor agents.

Toward playing with the data: I tried to get in touch with the authors a few times in the past with no success, so if you or a loved one are planning on having dinner with Dr Wiley in the near future, please let him know that I would love to swim a circle around his dataset and gobble it all up.

Scientifically.