Behavioural ecology and navigation in peacock mantis shrimp

Martha M. M. Daniel

University of Bristol

This November, I spent 20 days in the Maldives observing and recording the secret lives of peacock mantis shrimp, together with my colleague and dive master, Dr. Matteo Santon. These captivating little predators are most famous for their ability to punch faster than sound, which produces vacuum bubbles, light, and heat. They also have complicated eyes that have fascinated several generations of scientists and continue to challenge our imaginations. Still, we do not know how these animals move through and interact with their wild habitats. Such insights would provide much-needed context for past research about how mantis shrimp see their world, while also enabling new experiments that explore visual attention and decision-making.

Our quest was to address this gap in knowledge, since the second stage of my PhD work focuses on the navigation of mantis shrimp. The fieldtrip proved both a rewarding and exhausting undertaking. From the day after our arrival on Kuredu Island, Matteo and I embarked on two 90-minute SCUBA dives each day, armed with GoPros on selfie sticks and a plan that we knew would change during every dive.

On some dives, I spent the entire 90 minutes waiting for a mantis shrimp to leave its burrow, which entailed lying as still and low as possible, not too close but not too far away. On other dives, I spent the whole time swimming against a current to follow the mantis shrimp with a GoPro, being careful not to loom like a potential predator. The animals would often disappear from view, requiring us to anticipate from which hole they might emerge, and how soon.

In the end, we came away with more video data than I had ever dared to hope for. By the third day of the trip, we had been lucky to find four mantis shrimp living in the same small stretch of reef, their burrows located only a few meters apart. This was an opportunity not to be missed, so we visited the same area of reef on every dive, until we ourselves were feeling at home there. As the individual personalities and conflicts of these animals unfolded, it became apparent that mantis shrimp use their habitats in a much more dynamic and complex way than we anticipated.

However, to really show this, I also need to create a 3D map onto which I will be able to plot the positions of the mantis shrimp as they moved through the habitat. For this, we built a simple two-camera rig that allowed us to collect overhead videos of the reef. I cannot wait to plot the tracks of these animals and explore the patterns that stand to emerge!


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I am in the second year of my PhD program, which is based at two universities, the University of Bristol, UK, and Macquarie University, Sydney, AU. My supervisors are Dr. Martin How in the Ecology of Vision Group (Bristol) and Dr. Ajay Narendra in the Ecological Neuroscience Group (Macquarie). I came to this PhD project with separate experiences in both marine biology and sensory behaviour research, so it is exciting to finally be combining the two.