This is a study about studying whales! Although we already intuitively knew it, it is hugely helpful to have this put into facts and numbers. Indeed, whales are poorly studied around the world, arguably with the exception of the eastern tropical Pacific, and areas of the North Atlantic/Arctic oceans. Indeed, there are huge knowledge gaps in the world map and we still have very poor coverage of these magnificent, elusive and mysterious animals.
One such looming gap is our study site in the eastern south Pacific and the south of Chile. So I hope in my research lifetime to see this map a little fuller!
Read more: http://www.sciencedaily.com/releases/2012/09/120917085533.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Fplants_animals%2Fdolphins_and_whales+%28ScienceDaily%3A+Plants+%26+Animals+News+--+Dolphins+and+Whales%29
Wednesday, 19 September 2012
Thursday, 16 August 2012
Some interesting research about anthropogenic underwater noise decreasing whale communication from our partners at Cornell...
Here is some interesting research about anthropogenic underwater noise decreasing whale communication. This has come out of the Cornell Lab of Ornithology who we are currently working with on the hydrophone (MARU) deployments in the Corcovado feeding ground.
Read more at: http://www.sciencedaily.com/releases/2012/08/120815142050.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Fplants_animals%2Fdolphins_and_whales+%28ScienceDaily%3A+Plants+%26+Animals+News+--+Dolphins+and+Whales%29
Read more at: http://www.sciencedaily.com/releases/2012/08/120815142050.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Fplants_animals%2Fdolphins_and_whales+%28ScienceDaily%3A+Plants+%26+Animals+News+--+Dolphins+and+Whales%29
Thursday, 19 July 2012
The complex use of dolphin sonar in bubbly water and its engineering implications
Do dolphins benefit from nonlinear mathematics when processing their sonar returns? The title of an interesting and complex study of dolphin sonar from the University of Southampton UK, looking into how dolphins process their sonar signals in bubbly water, produced by their very own bubble nets for hunting fish, which would confuse the incoming signal making it difficult to distinguish between bubbles or fish. However, researchers found that if these animals have non-linear signal processing capabilities (as opposed to linear) then sonar signals of bubbles and fish are differentiable. The application of non-linear signal processing has implications for the engineering of man-made sonar, enabling targets, such as sea mines, to be distinguished that would be missed by conventional linear signal processing.
I am not at all a whiz when it comes to signal processing theory, but the crossover between the use of sound in dolphins and human engineering is interesting, and shows how complex and how little we still understand about these highly evolved beings.
Read the article on the University of Southampton website: http://www.alphagalileo.org/ViewItem.aspx?ItemId=122555&CultureCode=en
I am not at all a whiz when it comes to signal processing theory, but the crossover between the use of sound in dolphins and human engineering is interesting, and shows how complex and how little we still understand about these highly evolved beings.
Read the article on the University of Southampton website: http://www.alphagalileo.org/ViewItem.aspx?ItemId=122555&CultureCode=en
Thursday, 28 June 2012
Rescuing the buoys: The MARU recovery trip!
Rodrigo Hucke (Centro Ballena Azul/Universidad Austral de Chile), Luis Bedriñana (Centro Ballena Azul/Universidad Austral de Chile), Fred Channell (Bioacoustics Lab, U. Cornell) and myself cruised onboard the Yagan II, a 50t 18m fishing boat, between the 16th and the 25th of June from Chiloe, through the Corcovado Gulf, out to the Boca de Guafo, back across the Moraleda Channel, over to the continent and Tic Toc Bay, and then back to Chiloe again.
Our mission was to recovery 6 MARU (Marine Autonomous Recording Unit) sound buoys placed around the Corcovado Gulf blue whale feeding ground. These buoys were deployed in January and have been recording blue whale sounds for the past 5 months and will help us find out some key information on their movements and song dialects.
The weather was tough and we had alot of waiting around for ports to open. Unfortunately, 2 out of our 6 buoys were not recoverable, they answered us but they never surfaced. The other 4 were recovered fine, we sent them the 'release' sound signal, they responded to the signal, released their anchor and then floated to the surface in the vacinity of our boat. We also deployed a 7th buoy to replace one of the ones we lost. So all in all we got the job done! And were happy and relieved to go home...
Here are some photos:
Our mission was to recovery 6 MARU (Marine Autonomous Recording Unit) sound buoys placed around the Corcovado Gulf blue whale feeding ground. These buoys were deployed in January and have been recording blue whale sounds for the past 5 months and will help us find out some key information on their movements and song dialects.
The weather was tough and we had alot of waiting around for ports to open. Unfortunately, 2 out of our 6 buoys were not recoverable, they answered us but they never surfaced. The other 4 were recovered fine, we sent them the 'release' sound signal, they responded to the signal, released their anchor and then floated to the surface in the vacinity of our boat. We also deployed a 7th buoy to replace one of the ones we lost. So all in all we got the job done! And were happy and relieved to go home...
Here are some photos:
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| The working deck on Yagan II. Credit: Luis Bedrinana |
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| Sending the buoy a signal and waiting for the answer... Credit: Luis Bedriñana |
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| A MARU at the surface.
Credit: Luis Bedriñana |
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| A MARU at the surface with some growth on it.
Credit: Luis Bedriñana |
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| Spotting the MARU and pulling it in... Credit: Luis Bedriñana |
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| Pulling in the MARU... Credit: Luis Bedriñana |
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| The MARU on deck! Credit: Luis Bedrinana |
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| Turning the buoy off once on board. Credit: Luis Bedrinana |
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| The anchor connection before release. Credit: Luis Bedrinana |
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| The anchor connection after release, leaving the anchor plate on the sea floor. Credit: Luis Bedrinana |
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| Fred talking to the replacement buoy before dpeloyment. Credit: Luis Bedrinana |
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| Getting the MARU ready for deployment. Credit: Luis Bedrinana |
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| Deploying MARU 7. Credit: Luis Bedrinana |
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| Deploying MARU 7. Credit: Luis Bedrinana |
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| MARU 7 ready for deployment. Credit: Luis Bedrinana |
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| A blue whale when we were deploying MARU 7! Credit: Luis Bedrinana |
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| Capitan Espana, me, Oliver (first mate), Fred and Rodrigo. Credit: Luis Bedrinana |
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| Piratas! Credit: Luis Bedrinana |
Squid and octopus are also affected by ocean noise pollution
We are learning more and more about the effects of ocean sound pollution on marine organisms: beyond marine mammals, it seems that squid and octopus are also affected (suffer acoustic trauma) by noise pollution in the ocean. Squid, furthermore, are key prey items for sperm whales.
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Friday, 15 June 2012
Winter research in Melimoyu: a selection of photos
We left Melimoyu on the 13th of June after a great three week stay. I am very pleased at how good the weather was and how much we were able to go out to sea and sample. Here is a selection of the best photos from our very successful winter campaign:
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| Arriving in Melimoyu on the Pincoya. Credit: Oliver Alarcon |
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The Patagonia Sur research vessel: Chucao I.
Credit: Oliver Alarcon |
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| Preparing the phytoplankton net. Credit: Oliver Alarcon |
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| Up comes the phytoplankton net! Credit: Susannah Buchan |
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Hauling up a heavy zooplankton net!
Credit: Alex Machuca |
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| Zooplankton net and Melimoyu volcano in the background! Credit: Alex Machuca |
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Krill sample.
Credit: Sebastian Yancovic |
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A bigger-eyed, deeper-water species of krill that we have found in these winter trawls: Nematocelis megalops.
Credit: Sebastian Yancovic |
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A pipefish in our trawl sample (Sygnathus sp).
Credit: Sebastian Yancovic |
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| Rough seas! Credit: Susannah Buchan |
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| Oliver bringing up the Niskin bottle for collecting seawater samples. Credit: Sebastian Yancovic |
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| Bottling the seatwater sample from the Niskin bottle. Credit: Sebastian Yancovic |
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| Our samples! Credit: Susannah Buchan |
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| The dappled back of a blue whale on the 7th of June. Credit: Oliver Alarcon |
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| Frost on the Patagonia Sur guest house. Credit: Oliver Alarcon |
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| Black-browed Albatros and the Melimoyu volcano. Amazing! Credit: Oliver Alarcon |
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| Reading the Multiparameter sensor. Credit: Sebastian Yancovic |
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| Casting the CTD sensor... Credit: Sebastian Yancovic |
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| Up comes the CTD! Credit: Sebastian Yancovic |
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| Melimoyu volcano and clouds... Credit: Susannah Buchan |
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| Melimoyu volcano and more clouds... Credit: Susannah Buchan |
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| Leaving the Gulf behind and entering Refugio Channel after a long day of sampling... Credit: Susannah Buchan |
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| Sunset in Melimoyu Bay from the house. Credit: Sebastian Yancovic |
Monday, 11 June 2012
4 blue whales on the 7th of June!
On the 7th of June we spotted 4 blue whales in our study area! One was clearly feeding and so we made sure to sample that specific spot to see what the whale was targetting. Our trawl picked up a different krill species from the one most common in summer.
The theory is no whales outside the summer months in feeding grounds, i.e. December-April in Chilean Patagonia. However, worldwide this is now being questioned. It may be that a fraction of a population (but we don't know how important a fraction) stays in feeding grounds year-round, which would make sense especially for non-reproductive individuals. In effect, local fishermen in this area have provided anecdotal evidence over the years of whale sightings in winter. But this info has yet to be quantified and presented in the literature, or to decision makers.
We will know more once we look at the acoustic data up until June, and the data from this winter campaign.
All this info is key from a conservation management and eco-tourism perspective
Exciting news!
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The dappled back of a blue whale on the 7th of June.
Credit: Oliver Alarcon |
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