Tag Archives: Birds

Filming the Diving Boobies

Originally published by ReefWatch SA on 6 June 2016.

 


http://www.arkive.org/brown-booby/sula-leucogaster/image-G58180.html

It seems like every week there is a new way that technology is helping us to understand the world around us. From flying drones to genetic testing, advances in technology are allowing us to see the world in a new light and new ways. This month, the wonders of technology have helped us to better understand Boobies, predatory seabirds who feed on squid and fish.

A group of researchers from around the world, led by The University of Sydney used GPS loggers, tiny cameras and nutritional information to see how climate change has affected their hunting abilities. Warming temperatures and ocean acidification are changing the migratory patterns and ranges of fish, squid and marine invertebrates across the world. This means that predators such as the Masked Booby need to change their own patterns of movement.

Predators often balance the need for energy with the energy expended when hunting. Think of cheetahs that all of a sudden stop chasing a gazelle. They may be able to catch their prey, but if the energy they use to do it is higher than the energy they will gain from the food, then this becomes pointless. The same principles apply to all predators. Masked Boobies catch their prey (mostly fish), by diving on top of the hapless fish. Travelling across the ocean from their breeding sites requires a lot of energy (after all, flying can’t be easy), so it is a very intricate balance between energy used and energy gained.

With the movements of fish, the research team found that Masked Boobies are currently travelling an average of 50 km from their breeding sites to hunt. The research team used a combination of camera data and nutritional information to judge how this energy exchange occurs and also to better understand what species of fish these Boobies tended to consume. This is going to be very useful information with the future predictions of climate change – the more we understand, the easier it will be to protect these beautiful creatures against future climatic issues.

Original research:
Machovsky-Capuska et al. (2016) Coupling bio-logging with nutritional geometry to reveal novel insights into the foraging behaviour of a plunge-diving marine predator. New Zealand Journal of Freshwater and Marine Research. DOI: 10.1080/00288330.2016.1152981