SEA Blog

A change of pace -- more success...

Today was an amazing one for SOCAL-10 – and a number of new accomplishments.  Two weeks ago on the scouting leg for this project, we attached a satellite-linked monitoring tag to an adult male sperm whale fairly close to where we have been operating recently.  The satellite tag provides the chance to monitor the movement of the animal at a fairly coarse level but for a long time.  We had been watching this animal’s movement each day to see if there might be an opportunity to re-sight him and attach an acoustic tag.  Yesterday we got close and were pretty sure we heard him.  Today we found him.

 

                    

Photo credits (A. Friedlaender)

We used the satellite data to find the general area and then switched to acoustic sensors to get a more specific bearing.  After hearing him we closed in until we got a visual sighting and began our focal follow.  There is a very different mode of operation for working with very deep diving whales like sperm whales than the blue and fin whales we have been studying, and it requires an integrated approach using both visual detections when the animal is at the surface and listening sensors during their fairly long and deep dives.  We shifted into this mode very well today, using both sonobuoys and dipping hydrophones with directional capabilities.  The image below shows two different ways of looking at the calls of the whale and the sounds produced in our experiment - the top is a waveform showing the raw voltage signal we are receiving and the bottom is a spectrogram which is like a sound voiceprint of what the whale and sound around it look like in terms of their pitch and loudness.  On the bottom plot you can see the whales sounds as verticle lines (they sound like short, sharp bangs basically) and the sound from our experiment as slightly longer, intermittent, stacked horizontal bands (which sound more like notes on a piano).

(Image courtesy D. Moretti)

Using all our visual and acoustic tools, we followed the whale and by mid-morning we had a second tag attached, this one a short duration, high resolution acoustic tag to measure the fine-scale reactions to our sound exposure.  The controlled exposure experiment was initially postponed by about an hour because we had California sea lions close to our sound source, but was eventually conducted to the full duration during one of the sperm whales deep dives.

After the playback, we continued monitoring the whale, switching between our visual team when the animal was on the surface and the acoustic assets when the animal was on relatively deep dives.  Interestingly, a group of bottlenose dolphins was following the whale each time it was at the surface (perhaps to try and grab a bit of something to eat it may have brought up from depths they can’t reach?) and we began to use their tracking as a way of predicting where the whale would surface as well.  This biological indicator may have been as good as ours, but using all these tools, we tracked the whale from a distance for seven hours and left in the evening with our tag still attached.  Tomorrow we will track down the tag, with our data from this interesting and unprecedented experiment riding on board, and then probably switch gears back to blue/fin whales for the next few days.  Hopefully the weather and the animals will continue to operate as we continue to move into new areas around southern California

                  

                                                         Photo credit (A. Friedlaender)

Blue whale skin and a baby fin...

Last night we had four tags spend the night on whales and our first order of business today was to try and locate all of our equipment.  We found the two location and depth tags quickly, and one of the acoustic monitoring tags soon thereafter, but one remained attached to the whale.  Interestingly, there is a lot of skin sloughing off of these blue whales and it is interfering with the release mechanisms of some of the tags by clogging up the suction cups that attach them to the animals by preventing air from getting into the suction cups to allow them to release from the whale.  We can keep monitoring the radio transmissions from the tags while getting some other work done, and we are very confident that we will get the other tag back – it just may take some time and effort.  Likewise, we will now have at least a 24 hour tag record of blue whale behavior, something very valuable and uncommon!

While the small boat was picking up our tags with yesterday’s SOCAL-10 data we went into survey mode and quickly found mixed groups of blue and fin whales that were generally nearer shore and behaving differently than many of the groups we have been working in the last few days.  They were diving a bit more and being slightly less conspicuous at the surface than the lunge-feeding whales we have been working.  We soon attached two different acoustic tags to one blue whale and another acoustic tag to a second whale.  The below picture shows the methodology used with two taggers in a small boat simultaneously tagging the same whale on one close approach with two different monitoring tags.

      

(Photo courtesy J. Calambokidis, Cascadia Research) 

As we conducted baseline monitoring of the tagged whales in preparation for a CEE, we continued to monitor our range to shore as the whales were inching closer to our 1nm sound limit (no sound transmissions inside this range).  To the left is a photo of a Dtag riding on the back of one of the blue whales used in the experiment.  (Photo courtesy A. Friedlaender). 

During this baseline monitoring, we sighted what we thought was a mother-calf pair of fin whales so we held off on the CEE to confirm.  We determined that in fact it was a very young fin whale, certainly younger than the 6-month criterion we use to define neonates, the presence of which precludes our starting sound transmissions. 

Eager to make some use of the fact that we had two tagged whales wearing three tags, and with the need and capacity to include experimental controls, we maneuvered into position as if we were going to transmit sounds, did everything exactly the same, and ran through a complete monitoring and “mock” CEE where we deployed the source and conducted all focal observations but did not play any sounds at all.  This is a useful control for us in fact to test whether and how much of an effect the presence of our sound source vessel itself may have on the animals regardless of sound exposure.

In addition to the fin whale calf, a few other interesting observations were a blue shark that had been severely injured by fishing gear, a breaching blue whale, and the sperm whale that we attached a satellite tag to several weeks ago sneaking closer to our current area.  We may try to relocate it in order to attach an acoustic tag and conduct a CEE, which would be interesting and unprecedented with the much longer positional baseline and movement after sound exposure.  The rest of the day was spent tracking our two acoustic tags (one from yesterday and one from today) that are still attached to whales because of the sloughed skin clogging the suction cup releases (both were just recovered, well after dark -- yes!).  Three more tags today with a large amount of baseline data  and a “mock” exposure sequence with no sounds – pretty good success on a beautiful sunny day just off the southern California coast.

 

 

(Photo courtesy A. Friedlaender)

Four whales, five tags, three CEEs = good end to first week of SOCAL-10

We pushed off at dawn today and within an hour were on multiple workable groups of whales.  It was quite calm with light seas and totally overcast early and the whales were feeding all around us.  Check out a recently-posted video <http://www.facebook.com/pages/Behavioral-Response-Studies-of-Marine-Mammals/153316228012219> of a nearby blue whale performing "lunge" feeding on the vast plumes of krill around us (courtesy C. Kyburg). 

Within eight minutes (!) of moving into tagging mode we had two different acoustic tags on each of two different blue whales and began conducting baseline observations of behavior.  After the baseline monitoring interval, we positioned the sound source boat in a good location just under 1000m from one of the focal tagged whales.  In the baseline monitoring interval the other whale had moved quite a ways away – about 4000m – but we had one of our small vessels monitoring the animal for the controlled exposure experiment as well.

The CEE went flawlessly, with excellent spacing among the animals and vessels, and we had an acoustic monitoring hydrophone within a few hundred meters of the tagged whale and even closer to an animal that wasn’t tagged but that we were monitoring during the CEE with focal observations.  The observations on this individual were used as a “tagless” playback but we had not only the focal visual observations, but a recording hydrophone from a sonobuoy very near by to measure the sound received very close to the animals.  This was a fortuitous and very cool aspect of what evolved as a picture-perfect experiment.  Here you can see a non-tagged whale swimming near the surface float (orange) for a sonobuoy, which drops a line with a listening sensor hundreds of feet below the surface for acoustic monitoring (photo courtesy C. Kyburg).

After the exposure phase of the study, the sound source vessel and larger visual observation platform (R/V Truth) took over on focal monitoring for one of the whales and one of the small boats headed out into much deeper water to search for beaked or sperm whales.  While we have been pretty focused on large whales (blue, fin, and sei thusfar), we have built in the flexibility and capability to switch gears and go after some of the smaller cetaceans like beaked whales that are likely to be more responsive to sound exposure.  Once we got our acoustic tag back, the Truth also headed offshore to provide visual support in search of deeper-diving whale.  We saw several offshore dolphin species, but no beaked whales in our search.  Meanwhile the other small boat managed to attach two other diving and location tags on two other blue whales near the incredibly busy shipping lanes leading into LA/Long Beach.  

The relatively large number of close approaches and near-vessel strikes of whales in our brief time on the water, such as this example from this afternoon (courtesy J. Calambokidis, Cascadia Research), is a clear reminder of the many human impacts on these remarkable and important animals. 

Overall we had five tags on four whales and conducted a CEE to two tagged and one untagged focal whale today while scanning several hundred square miles of ocean for new options tomorrow.  We are sensitive to not forgetting how hard this actually is to do (despite it seeming somewhat automatic) or that things could go south in a multitude of ways, but suffice it to say that 20 tags and 11 playbacks in week one of SOCAL-10 has us moderately “stoked” as they say here in California.

Friday's results -- more of the same

We're on a hot streak and are dealing with so much data and logistics it's a little hard to keep up with the blog every night.  So here's yesterday's and tonight I will put up a post from our (great) day today.  Yesterday (Friday) started out in pretty heavy fog.  We tried to survey areas off Palos Verdes where we had surveyed yesterday, but the fog was just too heavy. We headed south, passing up several areas where there were too many whales in a small area, and had several hours worth of following small groups of whales that seemed to be intermittently traveling and feeding until we got into workable conditions for tag attachment.

By mid-morning we were able to deploy tags on a fin whale and a blue whale in the same general area; each whale had a Dtag and a Bprobe on it with solid attachments and good radio transmissions.  A large group of common dolphins came into the area and we waited for them to clear out of our immediate area. After several hours of baseline monitoring, we conducted a great, complete sound transmission (30 min total) with both whales each of which still had both tag types attached. There was one other whale in the area and a small group of common dolphins that swam through the area when the source was transmitting at full power (but not inside our 200m safety zone), though the all continued traveling and/or feeding.  Much of the rest of the day was spent tracking the focal whales and recovering all four of the acoustic tags used in the experiments.

Throughout the day we came across scattered groups of common dolphins, thrashing fish, and sea birds feeding on krill and other bait patches, and lots of blue and fin whales. Another successful dual deployment with double tags, good scouting for planning tomorrow’s strategy, and an amazing sunset on a calm sea. Nice.

(photo credit: G. Schorr)

After a slow day...more SOCAL-10 success and a first!

The SOCAL-10 team had another really successful day today despite being in marginal wind and sea conditions.  It seemed like quite a long day, especially for the small boats, because we were getting bounced around quite a bit driving mainly north and into the waves.  But the minor challenges of holding on and getting splashed occasionally were soon overcome by some exciting developments.

Shortly after we hit the water we saw two whales traveling together.  Several days ago we identified an adult sei whale, which you can see feeding in a recent post on our FaceBook page: http://www.facebook.com/pages/Behavioral-Response-Studies-of-Marine-Mammals/153316228012219.  This morning we found this individual again, though it was clearly traveling with a fin whale.  After some effort, we managed to obtain high quality photographs, attach a long-term, position-monitoring, satellite tag, and obtain a small tissue sample with a biopsy dart to provide genetic confirmation of the identity of the animal (see below - courtesy E. Falcone).

Where and how individuals of this species move in these areas of southern California is almost completely unknown and we should now have weeks or months of information from it’s movement tracks.  This finding is particularly exciting since sei whales, while having commonly been taken in commercial whaling are rarely sighted in the eastern North Pacific, leaving their recovery status uncommon.  We were all excited about this first-of-its-kind accomplishment.

Shortly thereafter, one of our RHIBs attached not one but two different kinds of acoustic and position sensors to a blue whale.  This provided a very useful means of comparing the data from different tags measuring similar things from the same animal during sound transmissions.

 

As D. Moretti prepared the sound source (above, courtesy C. Kyburg) and moved into position for a controlled exposure experiment, we managed to attach another Dtag to a second blue whale (seen lunge feeding in the picture below - courtesy G. Schorr).

 

It was another successful and complete 30-min transmission interval (no mammals or turtles within 200m) with a total of six blue whales (two tagged) and one fin whale within sight.  We toyed with the idea of trying to move away and find other animals for a possible second playback later in the afternoon, but ultimately we ran out of time today.  However, on our way in, we did manage to spot a fairly large concentration of blue whales feeding in areas off Palos Verdes.  Overall, we remain extremely happy with our results, observations, and new discoveries in the first week of SOCAL-10, which are a testament to the outstanding team we are fortunate to have working so well together here.  Hoping for slightly calmer seas tomorrow…

Slow day

Well, after a blazing start to SOCAL-10 we had a slow day today.  All of the whales that had been in an area just off Oceanside have moved somewhere else (possibly to where we just were!) and likely because of a recent rapid warming of sea surface temperature in the area.  That and the significantly higher winds and seas today precluded any tagging of marine mammals by our team. 

We have put a few videos from yesterday's work up on the SOCAL-10 FaceBook page, see our most recent posts of a tagged blue whale and a feeding sei whale at: http://www.facebook.com/pages/Behavioral-Response-Studies-of-Marine-Mammals/153316228012219

Tomorrow we will be heading back to some of the areas where we had success the first few days of the project in locating various mysticete cetaceans (whales), including the fin whale depicted below (courtesy G. Schorr).

SOCAL-10 Day II -- Success (again)!

Yesterday was another successful day with quite good weather conditions.  We started out by searching for the two Mark-10 dive/position tags that spent the night on blue whales in San Pedro Bay.  We found one of them and had a good bead on the other but it was a ways away and we soon ran into mixed schools of blue and fin whales, so we decided to leave it and pick it up later (which we did). 

We moved into tagging mode and soon had two Dtags on fin whales in feeding aggregations of other fins and blue whales.  Later in the day we had a great view of a lunge feeding interval with a relatively uncommon (for this area) sei whale, as well.  The animals were predictably moving in fairly unpredictable ways in these mixed feeding aggregations and we had to continually work between the visual monitoring on the Truth and the small boats to keep straight who was who.  We monitored baseline behavior of both whales for several hours and around mid-day got into a good position for a controlled exposure experiment. 

One of the whales was several miles away during the sound transmission, while the one being monitored from the Truth visual observers was ~1000m as specified in our protocols.  It was a textbook exposure and we maintained great visual contact from the Truth and small boat and we had real-time acoustic monitoring from ship-based hydrophone and remote-deployed sonobuoy.  If you look closely at the below picture (courtesy C. Kyburg), past one of our visual observers on the Truth you will see a small orange float (which is the surface expression of the sonobuoy hydrophone) and our small boat closer to the whales during the sound exposure; it really was an optimal spacing of all our assets for monitoring the animals.

 

There were a number of other whales in the area during the CEE, including a blue whale that approached us to within 500m during the loudest part of the transmissions, but no animals came within our 200m shutdown zone and we ran the full 30 minutes of transmissions (one per 25 sec).  After the exposure study, we monitored the whales for several hours until we re-acquired the Dtags and moved on to scout out other areas for today effort.  We saw zero whales in an area where there were over 20 consistently a few days ago (that's nature!) so we'll continue searching in areas to the south.  Two days down and 7 tags attached with 4 CEEs – we are extremely pleased.

SUCCESS!!!

We had an AMAZING first full operational day on the water.  We left Long Beach harbor in fairly dense fog, with visibility as little as 100m at times and running the fog horn.  Both tag boats left ahead of us and had multiple sightings almost right away.  Both got Dtags on blue whales within an hour of starting and conducted focal follow observations for the next several hours.  The fog started lifting but was still heavy in spots and was far too limiting for the visual observation team on the Truth to commence operations and thus for us to consider commencing a playback.

 

  Courtesy: C. Kyburg

After about 2.5 hours of baseline behavioral observations by each small boat of each tagged whale (and the other three in the general area), visibility expanded to 2-3 miles enabling us to move into CEE mode.  Several fin whales were also in the area and continued to feed and track about 300-400m away from us, which was about half the distance to the focal blue whales.  We deployed the source, but ultimately picked it up and moved away from them and repositioned about 1 km from the focal blue whale group.  Once we determined all our pre-CEE conditions were met, we initiated sound transmissions while monitoring the focal group and all other animals in the area using our visual observers on the Truth and both RHIBs, while listening with monitoring hydrophones from the Truth and sonobuoys.  There were multiple other vessels in the area at times relatively near the animals.  In fact, we witnessed several more very close calls for collisions between whales and various boats throughout the day today.  We completed the CEE in the specified 30 min period and monitored the focal whales until the tags came off mid-afternoon and we retrieved them very soon thereafter. 

In the meantime, one of the RHIBs moved out into deeper water near some of the oilrigs to the east of Newport and managed to get two more monitoring tags attached to a blue whale.  The Truth moved ~8 miles out to the tagged whale and scanned the area, joining the visual monitoring of baseline behavior being conducted by the RHIB.  Once we determined that conditions were suitable for a CEE and we had several hours of baseline behavior, we moved into CEE mode for the focal whale, which we knew was not the same animals testing in the morning based on the distance and fact that we had just been monitoring them near Newport.  In the figure to the left (which is a hot-off-the-press draft from our second playback today) you can see our GIS plots of the position of the Truth and our tagging RHIB (Ziphid) showing the visual detections of our focal whale group (coded "C").  This information is available to us in real-time showing where all our assets are in space relative to the animals.  This helps us maintain the desired ranges and monitoring in a very dynamic situation, which is critical for decision-making.  It was a textbook source deployment and CEE with visual and acoustic monitoring until about halfway through the sound transmissions a California sea lion that did not see previously popped up right next to the boat looking at us.  We immediately terminated the sound transmissions, as required in our scientific research permit for any marine mammal or sea turtle within 200m. 

It was still a very productive and useful first day, despite the complications from other vessels in the first CEE and the shutdown in the afternoon one and we were extremely pleased with our progress – 5 tags (of three different types) attached on 4 different individuals with two separate CEEs to 3 focal animals with visual and acoustic monitoring and a demonstrated ability to rapidly terminate transmissions when necessary.  All in all, a resounding success for the first full field day of SOCAL-10.  Tomorrow we hope for similar success, starting with the recovery of our two tags still riding around on blue whales out in the full moon somewhere this beautiful evening along the southern California coast.

Close call for southern California blue whale documented

Today at the end of our southbound transit toward Long Beach, part of the SOCAL-10 research team witnessed a near miss between a oil tanker coming into harbor and a feeding blue whale. The whale ended up surfacing very close to the ship as it passed. Our small boat was 220 m away from the tanker and the whale was more than half way to the tanker so about 100 m or less, see below photo (credit: J. Calambokidis). 

At least four blue whales were killed by ship strikes off southern California in 2007, so they face a serious risk from ship strikes. Some of the research one of us has been conducting (John Calambokidis in collaboration with Erin Oleson and Megan McKenna and with the support of NMFS, Channel Islands National Marine Sanctuary, and Office of Naval Research) has been examining in what areas to whales and ships overlap and how they react to ship close approaches. Information from the BRS both in terms of observations like the one today but more importantly how they react to underwater noises, will be important for determining how best to mitigate threats whales face from ship strikes.

Southbound Transit, Scouting, and Source Test

Today marked the first operational day of the BRS phase of SOCAL-10.  We steamed from Santa Barbara harbor in the morning with our sound source and visual observer team aboard the research vessel "Truth" and our two smaller tagging boats.  Here you can see a picture (courtesy C. Kyburg) of some of our crew in action on one of the tagging "RHIBs" (rigid hull inflatable boat).

Based on the recently-completed scouting leg involving many of our team, we knew that most of the blue whales on which we will be focusing initially were in areas further to the south.  We headed in this direction and this in fact proved to be accurate.  Our main purpose today was to cover quite a large amount of water heading to the south in preparation for tagging and controlled exposure experiment options tomorrow.  So much of our day was spent in transit mode covering ground, but our RHIBs did locate and photograph some whales further to the south.  We all came across groups of common dolphins, California sea lions, minke whales, diving birds, and other animals, including blue whales near the end of the day (note the subsequent posting about a close call we witnessed for one blue whale around a large ship).

A major accomplishment today was the final testing and calibration of the SOCAL-10 sound source for use in the controlled exposure studies.  This was one of the few times that we actively looked for areas where there are not animals, and we did find a suitable location where no marine mammals were seen over a large area while we conducted the brief test.  This project is using a new and innovative way of transmitting relatively loud sounds during our experiments using an array of sound sources strung together and powered by a relatively light-weight series of amplifiers.  In the photo below, you can see the wetside of the sound source laid out on the back deck ready for deployment.

This picture is also courtesy C. Kyburg.  A note on photos regarding SOCAL-10 is that all photos taken in this project and published here are taken under and according to the conditions specified in our NMFS Scientific Research permit (#14534).

Finally, just a mention that the video presentation to accompany the SOCAL-10 BRS slides mentioned in the blog yesterday is now streaming on the project website at: www.sea-inc.net/SOCAL10

Thanks for all the supportive and emails about the project!