Just a short update from the field. Our planned 0400 release of the tag from the whale didn''t occur for some reason and our tag now totally full of data is still cruising around on our male beaked whale. We had indication of this at 0415 this am and then a few hours later started picking up the animal doing regular "shallow" dives of about 20-25 minutes at a time. We are closing in now and are just a few miles away. Trying to get the small boats closer to get a positive identification and ideally a picture of the tag. We have all day to look but are dealing with some fog, some fuel constraints and this being the last day of the project. All the data on this very important tag (because of how rare these tag outs are) is riding around out there. Will we get it back? Stay tuned....
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September 2010
09/30/2010
09/29/2010
Beaked whale bonanza...
Conditions started off just perfect today – almost no wind (Beaufort 0-1 conditions) and just a light swell. This is exactly the kind of conditions that you have to have if you stand any chance of finding and tagging the elusive beaked whale. We were forunate to have access to the wired listening range and we started off on a hydrophone that was active with beaked whale sounds. Soon there were Cuvier's beaked whale clicks on multiple phones to the south and west and we sent first one small boat then both in those directions, followed shortly thereafter by the Sproul.
Shortly, one of the small boats was on a group of five beaked whales and before we knew it they had tagged an adult male in the group with two other adults and two sub-adult animals. This was the first Cuvier’s beaked whale tagged with an acoustic recording tag in the Pacific and we were correspondingly excited. We immediately began preparing and checking everything for a rare and important sound exposure experiment, and continued monitoring the group with the tagged whale. This soon became complicated as the group of five was surrounded by not only ten other Cuvier’s beaked whales, but two Baird’s beaked
whales identified in the same area (about a 4x4 mile area). Seeing 17 beaked whales in a day is pretty uncommon, but was largely the result of just glass calm seas.
We sorted through who was who, focusing mainly on the tagged whale thanks to being able to monitor the radio frequency being emitted from the tag and synching it with visible surfacing behavior. In addition to the (unusual) complication of possibly too many beaked whales in the area all diving and submerging somewhat synchronously, we also had some weather to deal with. Right around the time that we were ready to start a sound exposure experiment, a heavy bank of fog rolled in. We have specific protocols for having sufficient visibility to monitor the area around the area of any sound transmissions to a range of 1,000m and we were at times down to 300m visibility, so we had to wait. With beaked whales, waiting from one deep foraging dive to another is a multi-hour exercise, and so it was noon before we were ready to go again.
Fortunately there was a several hour gap in the fog and the timing worked out well with their dive behavior, and the density of animals had dropped by that time so we were not exposing too many other animals incidentally as well as the focal whale. Monitoring of the whale during the exposure study was conducted by multiple acoustic sensors to ensure it was still diving and not reacting in some strong aversive manner. None was seen during the 30 min of intermittent sound transmissions, nor were any other animals seen to react in a strongly aversive way during the study. A dedicated post-monitoring survey of the area by multiple boats was conducted.
As often happens with beaked whales since they stay down so long (his earlier dive was about an hour) and can cover large distances under water, we didn’t find him again after the sound exposure dive. But earlier in the day, the tag had been seen to slip somewhat back and down on the animal so that the radio transmitter was less out of the water and was obstructed by the animal. The fact that it is not being received then (or now at night) probably means that it is still on the whale and will come off near or at the 0400 scheduled time tomorrow morning. We are scanning the area for the tag doing transect surveys and monitoring throughout the night on a regular basis. I will try to put up a post later in the night or in the morning when we are searching for and hopefully finding the tag with all our data on it.
This was the first controlled sound exposure experiment of any kind with simulated military sonar or other sounds, on a Cuvier’s beaked whale. These animals appear to be the most sensitive of the particularly sensitive beaked whale group and these are thus very valuable bits of information to have about responses in this species. We are not getting too excited until we get our tag back, but we are guardedly optimistic and happy that we were able to get done what has proven to be so very hard to do. It was an amazing day today and we saw Dall’s porpoise, two beaked whale species, lots of dolphins of different varieties, and omniscient sea lions as well, plus a 10-foot great white shark slinking along. Two days left for SOCAL-10 – it was nice to round things out with getting some work done on a high importance species like a beaked whale. It was the ninth different species tagged in this project.
Stand by for an update on the tag search and recovery. Right now nearing midnight we are burning squares into the dark, foggy ocean in a mile of water to the west of San Clemente Island…listening…
Photos courtesy A. Friedlaender, J. Calambokidis (Cascadia Research)
09/27/2010
Close calls and an old friend...
We started the day searching the edges of San Nicholas canyon fairly close to the dry, sparse island, looking for deeper-diving species like Risso's dolphins, beaked whales, or sperm whales. The weather was again very fortunate for us as the high pressure and offshore air flow that caused the scorching temperatures in southern California today benefited us and by the end of the day we would find each of these species and more.
By mid-morning we had a very nearby sighting of a single female Cuvier’s beaked whale. We followed her for several dives, but ultimately lost her on a deep dive and so we continued on along the 1000-1200m contours working around the canyon. Later in the morning, one of the tagging boats had a neat close encounter with a group of Risso's dolphins and nearly had another tag deployment on this rarely tagged species but just missed.
Throughout the morning we were getting sperm whale clicks and as we continued along past the island and into the Santa Cruz basin, we began narrowing in on the position of the animal with directional hydrophones. This turned out to be the same male sperm whale tagged earlier in this project that was re-tagged twice for controlled exposure experiments a week apart; he has now been sighted and identified four times in seven weeks. In the picture to the left you can see the little satellite tag riding on his back on the left side of the dorsal fin. [Photos courtesy A. Friedlaender]
Later in the afternoon we came across an animal that we didn’t immediately recognize and were excited that it might be a rarer beaked whale species, but it turned out to be a Cuvier’s beaked whale. Soon we saw two more and one of our small boats saw what was probably another pair as well. We tracked the animals through six or seven relatively shallow (400 meters is shallow for a beaked whale) dives, getting a read on their direction of travel and dive times. Shortly before sunset we came tantalizingly close to tagging an adult male Cuvier’s. The small boat had the tag pole within just a few feet of the animal and if it had surfaced one more time we would likely have tagged it, but it tucked under. These guys are just so very hard to get with how elusive they are and just spending a few minutes each hour at the surface. But if we get a few more encounters like today we expect to get there; it really takes the right combination of good weather, keen eyes and ears, and a little luck.
Forunately we have many options and other important species to work as well, and we have been very productive in working in the areas and on species that make the most sense given the weather and other factors of where we are. Tomorrow we will be working some edges where we may find fin or other large whales in slightly shallower water and Risso’s dolphins or beaked whales just further off the edge of a deep basin.
09/26/2010
Found the beaked whales...
...but no tags or controlled expoosure studies yet. We started out today with light winds and workable beaked whale conditions, but with building seas and expecting conditions to deteriorate later in the day. Our colleagues ashore who were listening on the monitoring hydrophones in areas where we were searching had some early clicks on two phones pretty close to our location and to the west so good visibility position. We launched the small boats and positioned around the detection location, but had no sightings or additional clicks detected.
By mid-morning we had some additional animals detected on a hydrophone on the western edge of the U.S. Navy's listening range facility off San Celmente Island. Within an hour we had visual confirmation of a group of four Cuvier’s beaked whales in water of about 1,200m depth. They were in two groups of two (two males and two females) and diving slightly asynchronously. We managed to get within about 100m of them, but not close enough to tag them. Around the time they went down for a deep foraging dive the wind really started picking up and by the time they came back up about an hour later, it was unworkable for tagging. So we pulled the small boats onto the Sproul and headed to some different water while continuing to search.
Several hours later the conditions improved sufficiently to be workable for beaked whales. Using the positioning provided by the listening range, we headed to an area where beaked whales had been heard. Soon we had a sighting of three Cuvier's beaked whale (two females and a juvenile) and quickly re-deployed one of the small tagging boats. We tracked them for another several hours until sunset and saw either three more individual animals or the group had split up into all singles. We followed them as we could in the dwindling light but didn’t manage to tag any. Seeing and tracking at least seven and maybe close to ten individual beaked whales today with marginal weather conditions for these elusive animals was encouraging, and perhaps a good sign for more animals in this area during our last week on the water. [Photos courtesy A. Falcone and G. Schorr, Cascadia Research]
09/25/2010
Blue whale diving
We thought it might be interesting to show you a dive record and some sound records from an acoustic and diving tag that we had riding on the back of a blue whale recently.
What you see on the back of this whale (tagged not far from downtown LA) is one of the new generation tags (called an "Acousonde" - made by Greeneridge Sciences, Inc) that we are field testing as part of this project. The new tag worked beautifully and you can see some interesting things about blue whale diving and vocal behavior from this plot.
If you look along the x-axis you will see time of day in military time and that the tag went on the animal about four o'clock in the afternoon (~1600) and the whale quickly resumed what were deep and presumably feeding dives to about 300 meters (see depth on Y-axis). Approaching sunset around seven p.m. (1900), you can see the whales dives become incrementally shallower until after dark the animal stayed quite close to the surface. It was probably following the layer of krill moving closer to the surface as night approached. Much of the subsequent nighttime activity was likely resting behavior.
However, when we look at the acoustic record from the tag during these nighttime intervals, we see some vocalizations coming from the tagged animal. These calls, seen in the figure below as fuzzy blocks in the time series between the three sequential spike series (which are the animal breathing) are characteristic of blue whales and are known as A-B calls. This is a kind of singing in male blue whales used in social interactions with other animals, presumably to attract females.
Images courtesy J. Hildebrand; Photo courtesy J. Calambokidis
09/23/2010
Another good day near shore...
With the offshore winds still up, we worked another day nearer to shore. Our first order of business was to pick up our new generation acoustic tag that was deployed for the first time yesterday. It was located by the radio signal being emitted by the tag and we soon had it in the boat dumping its contents into a computer.
By mid-morning one of our small boats found a group of about twenty Risso’s dolphins slowly traveling along the edge of a drop-off. This is a species we have been interested in working with, but were uncertain about the likelihood of tagging them with suction cup acoustic tags because of their relatively smaller size and previous tagging efforts. We approached them looking primarily to see about chances for doing a “tagless” playback whereby we would monitor their behavior during a sound exposure study while just monitoring them visually. However, as we worked closer to them, they seemed to be a relatively approachable group and we decided to try for a tag attachment. Soon we had an acoustic tag on one of the animals, but it only stayed on for twenty minutes. We retrieved the tag and tried again, with
the tag this time staying on nearly two hours. During this period, we managed to gather a good amount of baseline data and conduct controlled exposure experiment on the tagged animal, while conducting focal observations on the other animals in the group. After the experiment and our required post-sound- exposure monitoring, we moved about a dozen miles away around the Palos Verdes peninsula in search of other options for the afternoon.
Continuing our fortunate streak, we soon found quite a few whales spread out over a few miles and moved into tagging mode. We managed to tag one blue whale and conduct an afternoon controlled exposure experiment with it and a companion animal. This marks the next to the last (19 of 20 allowed) controlled exposure sequences with blue whales. We all remain somewhat amazed that we have been able to complete this number of experiments (n=27 total on four species). This is NOT an easy thing to do even once given all the pieces, requirements, and challenges; we know we have been fortunate in a number of ways.
We were blessed with another fantastic sunset, this one just behind Santa Catalina Island with the moon rising over a calming sea. Tonight we steam offshore with expectations of workable weather
conditions and hopes of tagging one of the much more difficult beaked whales or some other more deep-water species. We may be a little slow and pictureless with posts the next few days given how far out we will be, so thanks for bearing with us and thanks for the interest in our project.
Photo credits (A. Friedlaender, B. Southall)
09/22/2010
Operational again -- three tags and a playback
Well, SOCAL-10 picked right up where we left off two weeks ago for the first operational day of leg II. The forecasts were true and the offshore areas were not workable for our kind of small boat and tagging operations, so we worked in much the same mode and similar areas as in the first leg, focusing on fin and blue whales.
First thing in the morning we had to test out some of the new equipment and configurations of our project on this larger and somewhat more conventional ocean-going research platform. This entailed deploying our small boats from the back deck of the Sproul using a small crane and deploying the sound source from the vessels large A-frame.
Each of these tests went fine and our visual team adjusted well to the new configuration and platform and we were soon on whales. In short order, we had tags on two blue whales that were doing fairly long and apparently deep dives – just the configuration we were looking for without a lot of other animals around. After about an hour we were ready to go with a controlled exposure study, but one of the tags came off. So we re-positioned and later went ahead with the experiment with just one of the whales. Everything proceeded well until about 20 minutes into the transmissions when a small group of dolphins came traveling in, apparently ignoring the sounds, and came inside the 200m exclusion zone we are required to have clear during sound emissions. So that ended the experiment, but we continued to monitor the whale and recovered the tag near the
end of the day, just after deploying a newly developed acoustic tag that is being field tested as part of our project. Soon thereafter we recovered our small boats and began enjoying a nice sunset and a great moonrise over the California coastline. It’s good to be back on the water…
Photo credits: A. Friedlaender, B. Southall, J. Calambokidis (Cascadia Research)
09/21/2010
09/11/2010
END SOCAL-10 LEG I
We have come to the end of the first leg of SOCAL-10. This was the longer of the two phases of the project, lasting 20 days. Later this month there will be a second 10-day leg on the Scripps Institute of Oceanography research vessel Sproul. In the interim, there will probably be several posts relating to SOCAL-10, but there will likely be some other SEA, Inc. postings on related issues as well.
SOCAL-10 was incredibly fortunate to have some amazingly talented and dedicated experts in marine mammal biology, ecology, and behavior, as well as specialized acousticians and vessel operators. That, in combination with some favorable weather during leg I and the fairly large concentrations of whales near shore resulted in a very productive first leg. In total, we attached 54 tags of five differnt types (acoustic, diving, location-position) to individuals of seven marine mammal species (blue, fin, sei, sperm, killer, and Baird's beaked whale plus offshore bottlenose dolphin). We also had thousands of sightings and behavioral observations of these and at least eight other marine mammal species. We also completed 24 different controlled exposure experiments with individuals of three species using different sound types in different combinations.
While we are extremely happy with these accomplishments, we remain keenly aware of how difficult it is to carefully and safely track and monitor these animals, sometimes far offshore, and in difficult seas and weather, particularly for some of the trickier offshore species. During the second leg, we will likely be focusing a bit more on animals like Risso's dolphins, fin whales, beaked whales, and other more pelagic species and we are keenly aware that we may not keep pace with the level of tag attachments and CEEs as we had thusfar with mainly blue whales.
There were many, many people who made it possible to accomplish what we have thusfar, including our resource sponsors with the US Navy and all those involved in permits, logistics, and other aspects of the project. We also were very fortunate to have an incredible research platform and crew about the "Truth" out of Truth Aquatics @ SeaLanding in Santa Barbara. Please check in with us next week and look for regular SOCAL-10 posts to start again on or around 21 September.
(Photos above and below are courtesy E. Falcone and J. Calambokidis, Cascadia Research, and A. Friedlaender and B. Southall)