SEA Blog

End SOCAL-11 Leg I

We have come to the end of the first leg of SOCAL-11.  We worked offshore the last two days based on the forecast of light winds and calm seas, but this didn't entirely materialize.  We worked up by Santa Barbara Island in relatively low winds but moderate swell, looking and listening for beaked whales in deepwater canyons.  By noon the winds had come up enough to eliminate chances for locating and tagging beaked whales and we switched gears to try for more coastal species in the lee of the northern Channel Islands.  We didn't find them there, but yesterday we found several groups of fin whales, Risso's dolphins, and sighted two beaked whales.  The fog came in though, and it started raining a little, and despite hours of trying with different groups, we didn't manage to tag on our last day.

Nevertheless, the first leg of SOCAL was quite productive, with a total of 22 tags attached to 20 individual marine mammals (blue whales and Risso's dolphins), and 14 total controlled experiments conducted, each with detailed focal observations and monitoring before, during, and after sound transmissions.  I will be posting some additional details and images on our first leg in the coming weeks, and the planning for the second leg starting next month.  Thanks so much for all the people following our progress and for all the feedback.

Brandon Southall, Chief Scientist on behalf of SOCAL-11 team

 

Close...but no cigar

Well our offshore weather forecast didn't really pan out yesterday but we came close on a few priority species today.  We worked up from Catalina by Santa Barbara Island yesterday and had very good weather in the morning and searched for about 8 hours for beaked whales in workable weather, but as we got into the Santa Cruz Basin the wind picked up on top of the swell and other than a few fin whale sightings it was a wash of a day. 

This morning we woke up in the shaddow of a massive cliff under misty fog on the south side of Santa Cruz Island and it was calm.  This area to the south of the northern Channel Islands is relatively sheltered from the prevailaing winds from the northwest and also offers deep water fairly close to shore.  Within an hour we had a group of 5 fin whales with an offshore blue mixed in, some foraging Risso's dolphins and two likely beaked whale sightings.  For a time we had hopes of tagging multiple individuals and a mixed-species CEE in deep water, but ultimately we got in close on the fins a few times but no cigar with them or the blue, the Risso's had neonates in the group meaning we had to pass them up, we never saw the Risso's again.  Heading back to Santa Barbara at the end of Leg I and I will put up a little summary of our accomplishments when we are back in.

Closer on fins...finally good offshore weather

We've had some pretty good conditions in deeper water the last few days and have had success finding baleen whales in deeper water and have spent a lot of time searching for beaked whales as well.  From the picture below you can see the calm conditions we have had in 800-1000m kinds of water.  This has been great in terms of focusing on some key species in areas more like where they might be more likely to encounter real sonar.  For today and tomorrow (our last day of the first leg), we hope to have this weather in 1500m canyons way offshore where we would expect to be more likely to find the deep-diving beaked whales that are an important species in this study.  You can also see in this picture the safety helmets we have been using when tagging large whales. 
   

 

We spent last night on Catalina, but didn't really see it as we arrived after dark and left before sunrise, although we did watch masses of schooling flish flying around being chased by sea lions by our lights.  Kind of an aquatic fireworks display.  We will be out of touch working in the Channel Islands today and tomorrow so this may be the last posting before we finish tomorrow night.  Hopefully the offshore forecasts will ring true.  As we are pulling away from Catalina with bottlenose dolphins flipping out in our quarterwake it looks pretty smooth out here...

 

SOCAL BRS team at work

Hey everyone.  We've been working hard out here for the first 10 days of SOCAL-11, but we have also been having a little fun along the way and thought we would share a few photos from our team (including Cuidado the lucky gator) and places we have been.

 

 

 

   

 

Trying for beakers...got offshore blues

We had good weather offshore today and we tried for most of the day well offshore in good visibility species looking for beaked whales.  We surveyed fairly large areas of offshore banks and basins looking and listening, but didn't have any luck.  We came across several small groups and single blue and fin whales offshore and an aggregation feeding up on the shelf and by the end of the day we found a small group of blue whales feeding in quite deep water well offshore. 

The photo to the right shows a tag on the left side of a blue whale collecting data about the movement and sounds received (and made) by the animal (J. Calambokidis, Cascadia Research, collected under NMFS permit #14534).

We are still aiming for beaked whales and hope to have good conditions tomorrow morning out from San Diego.  However, we are quite interested in testing the differences in responses of marine mammals in the various kinds of habitats in which they live and are exposed to human sounds.  Today's CEE with offshore blue whales was very useful in that regard.

Working offshore

We've had fairly good to excellent seas offshore the past few days and have put in some time trying to work some of our more difficult/less common species like beaked whales and sperm whales.  In some of these offshore areas we might expect to find Risso's dolphins or fin whales as well.  Yesterday we had a number of likely detections of beaked whales with a few brief surface series, but these were single individuals and despite some concerted efforts we didn't manage to tag one. 

We have continued to maintain our mode of flexibility, though and later in the day yesterday as conditions deteriorated offshore we worked back in to nice waters and tagged two blue whales and successfully completed a CEE.  We are a little more than halfway through our first leg here -- 14 tags on blue whales with 8 CEEs and the 1 Risso's tag and CEE.  We'll be trying to work offshore again today -- with a little more fog on us than was the case in the below evening shot of beautiful Dana Point.

Tag and CEE on a Risso's Dolphin

Yesterday we attched one of the new generation DTags on a Risso's dolphin for almost nine hours and conducted a perfect CEE.  This was the longest successful attachment to date with the new version tags on offshore odontocetes and the first on a Risso's.  Below is a shot of the tag riding on the back of the animal who was in a group of about 20 that we followed most of the day.

 

Rissos dolphins are among our focal species for SOCAL-11 experiments.  We conducted one CEE on this species last year in SOCAL-10 and have been hoping for more this year.  This species has also proven somewhat difficult to tag in the past and our tags on last year were for just a few hours, so to get a nine hour deployment spanning several different behavioral modes was pretty exciting.  The tag came off late into the evening, but quite close to our anchorage and we made a beautiful late night ride in very calm seas and a red-yellow moon out to safely retrieve it. 

Slip Sliding Away...

In the last few days we have had a number of our suction cup acoustic tags slide around and ultimately off blue whales that we have tagged.  This isn't new or entirely unexpected, given that these animals, like all cetaceans, shed layers of skin quite rapidly.  Attaching anything to animals that have had tens of millions of years to become streamlined to live and move in water is no trivial feat, especially with suction cups on animals shedding skin.  We have managed to overcome this in many instances and have gotten a large amount of data already in the first full week of SOCAL-11, but we have lost a few tag attachments with tags sliding off.

Below is a picture we actually took last year of the volume of sloughed skin that can accumualte in these suction cups. 

We actually had the opposite problem last year of tags staying on longer because the skin jammed up the release mechanism, but the blues this year seem to be more slippery for whatever reason, whether differences in temperature, diatoms on their skin, or some other factor.

FYI - we will occasionally be posting some photos and short videos of our work on the SOCAL-11 Facebook page, which you can check out at:

http://www.facebook.com/home.php#!/pages/Behavioral-Response-Studies-of-Marine-Mammals/153316228012219

Finally, as I am posting this we are tracking a tag we attached earlier today to a Risso's dolphin.  This was the first long deployment (over 8 hours) of a new generation DTag and only our second deployment of any acoustic tag and CEE on this interesting species.  Right now it is beeping out in the dark ocean nearby occasioanlly as our dolphin comes up to breathe and a short signal is transmitted from the tag.  Stay tuned to see if we manage to find it.... 

Rollin with the blues...

Day five of SOCAL-11 and we have managed to attach eleven suction cup tags on ten different individuals and conduct CEEs on six different individuals.  So far we have just worked on blue whales in several different area, in part because the offshore weather hasn't enabled us to focus much on some of the deeper water toothed whales.

 

 

 

Two blue whales just off the southern CA coast (J. Calambokidis, Cascadia Research.  Taken under NMFS permit #14534)

We did see some fin whales today and now have an additional passive acoustic listening system being towed behind a quiet sailboat to try and detect vocalizing marine mammals in deeper water.  However, the weather haasn't proven too favorable to try and do this yet.  We have followed the MO of taking what the conditions give us and having the flexibility to work in different areas and on different species accordingly.  We are hoping for calmer weather offshore tomorrow, but the late forecast tonight isn't too optimisitc.  But, given the conditions we have had we are pretty pleased with the tags we have been able to attach and animals we have monitored.  Also, today was the first successful attachment of a new generation of tags on a mysticete cetacean; helping move the technology forward in a number of areas is something we are proud the overall SOCAL-BRS effort has contributed to.    

Tagging whales and mapping prey

Hi everyone,

My name is Elliott Hazen and I currently work for the National Oceanic and Atmospheric Association’s Environmental Research Division’s lab. Before that, I worked at Duke with Ari Friedlaender which is where I became involved with marine mammals and tagging. I am leading a small research project measuring prey and oceanographic variables around the tagged whales, before and after acoustic playbacks. The main task of my job is to understand which physical features are correlated with denser prey, and how these factors influence the whale behavior measured by the tag. These data can be used to inform our understanding of how baleen whales respond to the simulated SONAR.

I use a fisheries echosounder made by SIMRAD to measure the distribution and density of prey in the water column. The picture of the metal towfish has two orange echosounders, one operating at a high frequency (120 kHz) and one at a lower frequency (38kHz). Each echosounder emits a pulse of sound, similar to a dolphin echolocating, and measures the sound properties when it returns to the echosounder. We can figure out how deep layers of prey are, the shape of any detected schools, and how these prey patches change over time without a large impact to the prey. Our main limitation is that we cannot identify the species we are looking at acoustically. Luckily for us, in the case of a blue whale, we know they are eating krill. The screen shot shows an echogram from the 120kHz echosounder with higher acoustic densities in orange and red, and lower densities in blue to green, and the bottom shows up as a dark red. The echograms show time on the horizontal axis and depth shown vertically. This image is a good sample of what we’ve seen, specifically that the krill schools are denser near shelf breaks, such as where the bottom depth drops quickly from 100 to 180 meters. It also confirms what a colleague, Dr. Jarrod Santora has found for krill at a broader scale along the California coast. We hope this project will give us more information on how blue whales are making foraging decisions as we collect more fine scale measurements and more tag data from these large whales.