Interactions between baleen whales and krill

Minke whale; © Ari Friedlaender
A pod of minke whales, with one sporting a suction-cup tag.
A pod of minke whales, with one sporting a suction-cup tag (Photo: Ari Friedlaender)
An Antarctic minke whale spy-hoppingA satellite tag deployed in the blubber of a minke whaleWhale tagging team of four in small boatAn underwater image of a minke whale with the white ice above it.

Foraging ecology and predator-prey interactions between baleen (minke and humpback) whales and krill: a multiscale comparative study across Antarctic regions

Little is known about the dynamics of predator-prey interactions and the response of baleen whales to the distribution of their prey in the Antarctic. As a particularly important marine ecosystem (e.g. climate change impacts and international management of marine living resources) research focused on cetacean foraging ecology in the Antarctic represents a critical data gap.

Researchers are using novel tagging technologies combined with traditional scientific hydroacoustic methods to quantify the types and frequency of prey consumed and daily consumption rates of poorly understood yet ecologically integral and recovering krill predators in the Antarctic, the humpback and minke whale. Phase 1 involves collaborators from the USA and Australia, while Phase 2 will potentially include reserachers from Brazil, South Africa and Germany.

The project leader is Dr Ari Friedlaender.

Publications

Papers from this IWC-SORP project submitted to the International Whaling Commission can be found on IWC papers and reports.

'Mysterious bio-duck sound attributed to the Antarctic minke whale' [PDF] (2014) Biology Letters 10: 20140175. http://dx.doi.org/10.1098/rsbl.2014.0175.

'Distribution and abundance of Antarctic minke whales in sea ice regions of East Antarctica: a summary of results' [PDF] (2014) IWC.

'Extreme diel variation in the feeding behavior of humpback whales along the Western Antarctic Peninsula in autumn' [PDF] (2013) Marine Ecology Progress Series 494: 281-289.

'Humpback whales staying in Antarctic bays later into Autumn' (2012) Duke University-Nicholas School of the Environment News.

'Super-aggregations of krill and humpback whales in Wilhelmina Bay, Antarctic Peninsula' [PDF] (2011) PLoS ONE.

'Study sheds light on ecological ties of whales and krill' (2011) CORDIS Community Research and Development Information Service.

'Biggest ever assemblage of whales isn't necessarily good news' (2011) ScienceNOW.

Antarctic minke whale tagging
[Video]

Antarctic minke whale tagging

Video transcript

Australian Antarctic Division Chief Scientist – Dr Nick Gales

This was a combined voyage with the United States Antarctic Program and its actually focusing on both humpbacks and minke whales. The idea is to work in a place in Antarctica where both animals are feeding and have a look at how they feed differently.

Went down to a place called the Gerlache Strait, which is a beautifully protected stretch of water in among the islands off the western side of the Antarctic Peninsula and worked in the Bays there. It’s really productive, it’s an area where a lot of Antarctic krill move through the whole area. Sort of size of prey/patches at different depth and we have no idea what those are. So this was actually for minke whales, our first real insight into the differences between these two key species.

So we are using a whole range of different tags that are giving us different information and at the same time we have tags on we have boats going round looking at the prey, the depths at it and what’s in their environment.

So we go from the very short term tags, and we have to get these ones back, so you put a tag on the back of an animal, it’s held on by suction cups and it will stay on there for hours to perhaps one day. And then it will just fall off naturally, the suction cups will give up and it will float to the surface and we will retrieve it. And it measures everything. So we can tell the number of tail fluke strokes on the way down to the prey, pitch and role and turning through the prey and everything, so we get incredibly dense information and at the same time we measure with echo sounds from a separate boat where the krill are.

And then another type that we stick on the animal that have to stay longer. So these are fired through the skin of the animal and then they just embed in the blubber and the underlying tissue just below the blubber and they stay on, well we hope, for months. They just give us location, but they give us the middle to large scale movements of the whales. So where they go from those summer feeding grounds, how they move around those summer feeding grounds and we hope they last long enough to tell us where they go for their winter breeding.

We had no idea how minke whales were going to act around the small boat. They are a much smaller whale than the type of whales that we have a lot of experience in tagging and they are much faster. So the boat driver sits alongside a group of minke whales and slowly comes in on the boat until we are just part of a school of whales and then they are surfacing around us. Then it’s a matter of me on the bow, selecting a whale and then when that animal surfaces in the right range and the right distance from the boat shooting a tag onto the back of that whale. So it’s quite tense, but it’s really exciting when we successfully deploy the tags.

This summer is the very first time ever that these type of tags have been put on Antarctic minke whales, in fact any type of tag. So it’s really exciting we are going to combine the data and really bring forward brand new information about this species.

This page was last modified on July 26, 2016.