START SOCAL-13 PHASE II – Double Rissos

We’re very glad to be back together for this last phase of our SOCAL-BRS project for 2013. We pushed out from Santa Barbara yesterday and came south in pretty good weather. A group of humpback whales has been working in some mixed-species aggregations chasing fish in the Santa Barbara Channel and we came across a few of them right off the bat. We moved on with no tags deployed and searched deeper waters south of Santa Cruz Island. We found two different groups of Cuvier’s beaked whales (Ziphius cavirostris) near Santa Barbara Island and came fairly close to tagging one but didn’t manage to.

Today we had really fantastic weather for most of the day and we searched large areas offshore. We didn’t find any beaked whales but came across quite a few groups of Rissos dolphins (Grampus griseus). There were several good candidate groups and by early afternoon we managed to deploy two tags on adult animals in two different groups. Our controlled exposure experiment (CEE) focused on one group with the second tagged animal about 10 miles away. Tagging and CEE on two simultaneous Rissos dolphins (see tagged Rissos below – taken under NMFS #14534, credit J. Calambokidis) at different ranges is a new accomplishment for us in SOCAL-BRS and a good start to our final field phase over the next two weeks.

For more information on the SOCAL-BRS project, make sure to check out all the resources and photos in our blog and at


SOCAL-13 Phase I End


We have come to the end of the first full research phase for the SOCAL-BRS project in 2013. In terms of our success with the high-priority beaked whale species, this was the most successful period we have had in this project. We had two successful tag deployments (see above – taken under NMFS #14534-2, credit J. Calambokidis) and at least three other very close attempts with multiple groups. We had both successful visual focal follows over many “shallow” dives and acoustic tracking of focal groups through deeper foraging bouts covering many miles. Having multiple groups detected and tracked with multiple tags deployed and a full CEE sequence with workable weather for five straight days well offshore was unprecedented for us as well.

On the days we did not manage beaked whales we had lots of luck with Rissos dolphins (8 total tags, 4 CEEs), fin whales (2 tags, 2 CEEs – below photo taken under NMFS #14534-2, credit J. Calambokidis) and targeted deployments on blue whales (3 tags, 3 CEEs).


Another major development, as described in the public summary for this project linked to the SOCAL-13 page on <>, was our first coordinations with the U.S. Navy to coordinate with already ongoing training operations to have real military sonar systems used as sound sources in our CEEs rather than the small, scaled simulations we have used to this point. Our colleagues at the Navy just issued some additional information on this partnership and have more information about it available in several locations – please see:

Thanks again for following us out here and for the many comments and nice emails I have and continue to receive. We will be back for phase II in September and will resume the from the field blog at that point. We will have some additional updates and information on forthcoming presentations and manuscripts before then likely as well, as we have another paper coming out from the project soon.

Tagged blue whale (see gold DTAG attached to left side of the whale) with our research boat “TRUTH” in the background (taken under NMFS #14534, credit J. Calambokidis)




Big Whales and an Old Friend

We’ve been offshore for another few days on the first phase of our SOCAL-13 experiment and just back in to recharge for our last few days. We have had reasonably good conditions the last few days and have been searching for beaked whales but haven’t had the luck with them we had last week. We have had two tags out on a fin whale (above – taken under NMFS #14534 by J. Calambokidis) and a blue whale near the busy shipping lanes out of Long Beach.

After almost a whole phase of our project we hadn’t seen the sperm whale we had seen and documented on each field phase of this project since 2010. Affectionately known as Mango, an adult male sperm whale that has been identified in this area for over 20 years has been a regular occurrence for us out here. Apparently he knew we were almost done with our work for these two weeks as he made a cameo appearance yesterday allowing us to get some photo ID pictures to continue the long time series documentation of his movement (below taken under NMFS #14534 by A. Friedlaender).



Offshore bottlenose dolphin riding the waves in southern California (taken under NMFS #14534 by B. Southall)

Beaked whale bonanza!!!

Sorry for the radio silence with the SOCAL-13 blog. We have had very good offshore conditions and great success accordingly! In fact, the last five days have seen multiple beaked whale tags deployed and multiple groups seen with many other near-miss approaches, which is a first in our efforts out here. We have gotten two long tags deployed on Cuvier’s beaked whales, one of which involved a mid-frequency sonar controlled exposure, and gotten a ton of great baseline data as well on these very difficult to study species (see above and below photos on Cuvier’s beaked whale tagging and tag on – both taken under NMFS permit #14534 by J. Calambokidis).


We have also had great success with other species as well, including Rissos dolphins and blue whales (see below – taken under NMFS permit #14534 by J. Calambokidis).


At the moment we have two more blue whales tagged and narrowing in on a fin whale, planning for some mapping of the prey fields for these feeding whales and a possible experimental trial this afternoon. We may be offshore again tomorrow with great conditions forecast but will provide more updates when we can. Thanks for the nice comments and interest in our progress out here studying these amazing animals.


We are happy to report on the start of our SOCAL Behavioral Response Study for the 2013 field season (SOCAL-13). After several days of field efforts offshore we are back in internet range to provide an update on our progress. As a reminder for those of you following the blog or others that have just found it, we have lots of general information, photos, paper reprints, and informative links at the project website <>. Additionally, as noted in many of these documents and with photo credits, our work is authorized under U.S. NMFS permit # 14534, Channel Islands National Marine Sanctuary permit #2010-004, and are in accordance with a federal consistency determination of the California Coastal Commission. We are very fortunate in this project (thanks to the support of the U.S. Navy’s Living Marine Resources Research Program and the Office of Naval Research) to be able to study some amazing animals, measure aspects of behavior that are poorly known in many regards, and make controlled experimental measurements of their responses to sound. We have been committed throughout to an open and transparent process in providing information on our planned work and our progress. You can find project reports and public summary documents of planned efforts at the website given above.

The offshore weather hasn’t been great for the kinds of work we do (tagging marine mammals using non-invasive methods from small boats – see photo above). We have gotten to work early in the mornings in reasonable conditions and have typically found rougher to unworkable winds later in the day. Fortunately based on our experiences in the areas around the Channel Islands we adapted and found workable conditions and individuals of our focal study species with which to work. We have tagged two Risso’s dolphins (see below) as well as a blue whale in the past two days and conduct two experimental sequences. We have also had several acoustic and visual detections of Cuvier’s beaked whales – one of the highest priority yet most difficult species to work with – although we haven’t managed to tag one yet. We are ashore tonight to load up on provisions and fuel and reposition tomorrow for an offshore weather window starting Sunday that looks quite favorable. Look for more posts forthcoming in the next few weeks of phase I of SOCAL-13 – we will post information on our progress as we are able with internet access. Thanks for the interest and comments on the project to date – as mentioned, please see <> for more details.

Rissos dolphin with a Digital Acoustic Recording Tag attached with suction cups during SOCAL-13 (taken under NMFS permit #14534, credit: A. Friedlaender)

Ari Friedlaender Goes Ballistic

Check out our very own Ari Friedlaender in a recent Wired magazine piece along with Vladimir Putin:


A second paper from the SOCAL-BRS project was published today as well. This paper (in Biology Letters) presents results for the responses of beaked whales to both controlled and incidental exposure to mid-frequency sonar signals. The reference for the paper is:

DeRuiter SL, Southall BL, Calambokidis J, Zimmer WMX, Sadykova D, Falcone EA, Friedlaender AS, Joseph JE, Moretti, D, Schorr GS, Thomas L, Tyack PL. 2013 First direct measurements of behavioural responses by Cuvier’s beaked whales to mid-frequency active sonar. Biol Lett 9: 20130223.

This paper is available through Open Access as well at:

The abstract for the paper is given here:

Most marine mammal strandings coincident with naval sonar exercises have involved Cuvier’s beaked whales (Ziphius cavirostris). We recorded animal movement and acoustic data on two tagged Ziphius and obtained the first direct measurements of behavioural responses of this species to mid-frequency active (MFA) sonar signals. Each recording included a 30-min playback (one 1.6-s simulated MFA sonar signal repeated every 25 s); one whale was also incidentally exposed to MFA sonar from distant naval exercises. Whales responded strongly to playbacks at low received levels (RLs; 89–127 dB re 1 micro Pa): after ceasing normal fluking and echolocation, they swam rapidly, silently away, extending both dive duration and subsequent non-foraging interval. Distant sonar exercises (78–106 dB re 1 micro Pa) did not elicit such responses, suggesting that context may moderate reactions. The observed responses to playback occurred at RLs well below current regulatory thresholds; equivalent responses to operational sonars could elevate stranding risk and reduce foraging efficiency.



We are pleased to announce the publication of a new paper in the Proceedings of the Royal Society – B from our Southern California Behavioral Response Study on responses of blue whales to simulated sonar and other human sounds. The reference for the paper is:

Goldbogen JA, Southall BL, DeRuiter SL, Calambokidis J, Friedlaender AS, Hazen EL, Falcone EA, Schorr GS, Douglass A, Moretti DJ, Kyburg C, McKenna MF, Tyack PL. 2013. Blue whales respond to simulated mid-frequency military sonar. Proc R Soc B 20130657.

The paper is available through Open Access at:

The abstract for the paper is included here:

Mid-frequency military (1–10 kHz) sonars have been associated with lethal mass strandings of deep-diving toothed whales, but the effects on endangered baleen whale species are virtually unknown. Here, we used controlled exposure experiments with simulated military sonar and other mid-frequency sounds to measure behavioural responses of tagged blue whales (Balaenoptera musculus) in feeding areas within the Southern California Bight. Despite using source levels orders of magnitude below some operational military systems, our results demonstrate that mid-frequency sound can significantly affect blue whale behaviour, especially during deep feeding modes. When a response occurred, behavioural changes varied widely from cessation of deep feeding to increased swimming speed and directed travel away from the sound source. The variability of these behavioural responses was largely influenced by a complex interaction of behavioural state, the type of mid-frequency sound and received sound level. Sonar-induced disruption of feeding and displacement from high-quality prey patches could have significant and previously undocumented impacts on baleen whale foraging ecology, individual fitness and population health.

New Paper on Amphibious Hearing in Pinnipeds in Special Issue of Journal of Comparative Physiology (A)

SEA blog,

Please note the availability of a new special issue of Journal of Comparative Physiology (A) on Sensory Biology of Marine Animals (see below details and link). Within this issue is an original paper lead by Colleen Reichmuth at UCSC <> to which SEA’s B. Southall contributed. This paper is available on request.

Comparative assessment of amphibious hearing in pinnipeds

Colleen Reichmuth (1), Marla M. Holt (2), Jason Mulsow (3), Jillian M. Sills (4) and Brandon L. Southall (1, 5)

(1) Long Marine Laboratory, Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, CA 95060, USA

(2) Conservation Biology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. East, Seattle, WA 98112, USA

(3) National Marine Mammal Foundation, 2240 Shelter Island Drive, # 200, San Diego, CA 92106, USA

(4) Long Marine Laboratory, Department of Ocean Sciences, University of California Santa Cruz, 100 Shaffer Road, Santa Cruz, CA 95060, USA

(5) SEA Inc., 9099 Soquel Drive, Suite 8, Aptos, CA 95003, USA  

Journal of Comparative Physiology A

Neuroethology, Sensory, Neural, and Behavioral Physiology

Springer-Verlag Berlin Heidelberg

Volume 199, Issue 6, June 2013


Special Issue: Sensory Biology of Aquatic Mammals

 (13 articles)

Guest Editors: Wolf Hanke, Guido Dehnhardt

Editor-in chief: Friedrich G. Barth



Sensory biology of aquatic mammals

Wolf Hanke (1, 2) and Guido Dehnhardt (1, 2)

(1) Institute for Biosciences, Chair of Sensory and Cognitive Ecology, Rostock University, Albert-Einstein-Strasse 3, 18059 Rostock, Germany

(2) Marine Science Center, Am Yachthafen 3a, 18119 Rostock, Germany



Hydrodynamic perception in true seals (Phocidae) and eared seals (Otariidae)

Wolf Hanke (1), Sven Wieskotten (1), Christopher Marshall (2) and Guido Dehnhardt (1)

(1) Institute for Biosciences, Chair of Sensory and Cognitive Ecology, Rostock University, Albert-Einstein-Strasse 3, 18059 Rostock, Germany

(2) Department of Marine Biology, Texas A&M University, Galveston, TX 77553, USA 


Original Paper:

Detection of hydrodynamic stimuli by the Florida manatee (Trichechus manatus latirostris)

Joseph C. Gaspard III (1, 2), Gordon B. Bauer (1, 3), Roger L. Reep (2), Kimberly Dziuk (1), LaToshia Read (1) and David A. Mann (1, 4)

(1) Mote Marine Laboratory and Aquarium, Sarasota, FL 34236, USA

(2) Aquatic Animal Health Program, Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32610, USA

(3) Division of Social Sciences, New College of Florida, Sarasota, FL 34243, USA

(4) College of Marine Science, University of South Florida, St. Petersburg, FL 33701, USA


Original Paper:

Echolocation in Blainville’s beaked whales (Mesoplodon densirostris)

P. T. Madsen (1), N. Aguilar de Soto (2, 3), P. Arranz (2, 3) and M. Johnson (3)

(1) Department of Bioscience—Zoophysiology, Aarhus University, Build. 1131, Århus, Denmark

(2) Department of Animal Biology, La Laguna University, 38206 La Laguna, Tenerife, Spain

(3) Scottish Oceans Institute, University of St. Andrews, St. Andrews, KY16 8LB, Scotland



Gain control in the sonar of odontocetes

Alexander Ya Supin (1) and Paul E. Nachtigall (2)

(1) Institute of Ecology and Evolution, Russian Academy of Science, 33 Leninsky Prospect, 119071 Moscow, Russia

(2) Hawaii Institute of Marine Biology, University of Hawaii, Hawaii, USA



Communication in bottlenose dolphins: 50 years of signature whistle research

Vincent M. Janik (1) and Laela S. Sayigh (2)

(1) Sea Mammal Research Unit, School of Biology, University of St Andrews, Fife, KY16 8LB, UK

(2) Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA


Original Paper:

Comparative assessment of amphibious hearing in pinnipeds

Colleen Reichmuth (1), Marla M. Holt (2), Jason Mulsow (3), Jillian M. Sills (4) and Brandon L. Southall (1, 5)

(1) Long Marine Laboratory, Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, CA 95060, USA

(2) Conservation Biology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. East, Seattle, WA 98112, USA

(3) National Marine Mammal Foundation, 2240 Shelter Island Drive, # 200, San Diego, CA 92106, USA

(4) Long Marine Laboratory, Department of Ocean Sciences, University of California Santa Cruz, 100 Shaffer Road, Santa Cruz, CA 95060, USA

(5) SEA Inc., 9099 Soquel Drive, Suite 8, Aptos, CA 95003, USA


Original Paper:

Are harbour seals (Phoca vitulina) able to perceive and use polarised light?

Frederike D. Hanke (1), Lars Miersch (1), Eric J. Warrant (2), Fedor M. Mitschke (3) and Guido Dehnhardt (1)

(1) Institute for Biosciences, Sensory and Cognitive Ecology, University of Rostock, Albert-Einstein-Str. 3, 18059 Rostock, Germany

(2) Lund Vision Group, Department of Biology, University of Lund, Sölvegatan 35, 22362 Lund, Sweden

(3) Institute for Physics, University of Rostock, Universitätsplatz 3, 18055 Rostock, Germany


Original Paper:

Vibrissal touch sensing in the harbor seal (Phoca vitulina): how do seals judge size?

Robyn Grant (1, 2), Sven Wieskotten (3), Nina Wengst (3), Tony Prescott (1) and Guido Dehnhardt (3)

(1) Active Touch Laboratory, University of Sheffield, Sheffield, UK

(2) Division of Biology and Conservation Ecology, Manchester Metropolitan University, Manchester, UK

(3) Marine Science Center, University of Rostock, Rostock, Germany 

Original Paper:

Olfactory discrimination ability of South African fur seals (Arctocephalus pusillus) for enantiomers

Sunghee Kim (1), Mats Amundin (2) and Matthias Laska (1)

(1) IFM Biology, Linköping University, 581 83 Linköping, Sweden

(2) Kolmårdens Djurpark, 618 92 Kolmården, Sweden



The neurobiology and behavior of the American water shrew (Sorex palustris)

Kenneth C. Catania (1)

(1) Department of Biological Sciences, Vanderbilt University, VU Station B, Box 35-1634, Nashville, TN 37235-1634, USA



Passive electroreception in aquatic mammals

Nicole U. Czech-Damal (1), Guido Dehnhardt (2), Paul Manger (3) and Wolf Hanke (2)

(1) Biocenter Grindel and Zoological Museum, University of Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany

(2) Institute for Biosciences, University of Rostock, Albert-Einstein-Strasse 3, 18059 Rostock, Germany

(3) School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, 2193 Johannesburg, South Africa


Consciousness in dolphins? A review of recent evidence

Heidi E. Harley (1)

(1) Division of Social Sciences, New College of Florida, 5800 Bay Shore Road, Sarasota, FL 34243, USA

SEA’s Dr. Hugh Southall lead author on new publication on magnetic wave reflection

SEA Senior Scientist Dr. Hugh Southall has published a new paper in Microwave and Optical Technology Letters. Dr. Southall has long been a leading expert in signal processing, electrical engineering, and radar and antenna technology. SEA is very proud and privileged to bring his expertise to the new and challenging environmental issues on which we are working. This paper is just one example of his exciting and cutting edge research in applying complex signal processing and engineering solutions to tough question.



Hugh L. Southall,1 Bae-Ian Wu,2 and Jeffery W. Allen2

1 SEA, Inc., 2 Luan Circle, Chelmsford, MA 01824

2 Sensors Directorate, AFRL/RYHA, 2241 Avionics Circle, Wright-Patterson AFB, OH 45433-7320;

Corresponding author:

The article is available online through the following link:

Abstract: It has been shown that transverse electric plane waves reflect from certain types of metamaterials with a unit magnitude reflection coefficient (Smith and Schurig, Phys Rev Lett 90 &899;2003), 077405-1–077405-4).Here we investigate the reflection of transverse magnetic plane waves using a Hertzian dipole over a semi-infinite slab of metamaterial, which is used as a ground plane. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:899–903, 2013; View this article online at DOI 10.1002/mop.27454


SOCAL-BRS is a study of basic behavior and responses to controlled sound exposures in a variety of marine mammal species.

Southall Environmental Associates, Inc.

Reducing environmental impacts from essential human activities requires unique approaches to meet challenging conservation objectives in the 21st century. SEA, Inc. works globally with diverse scientific teams and cutting-edge technologies to provide real-world solutions. Learn more about SEA