This article has This been published in or collective redistirbution of any portion of this article by photocopy machine, reposting, or other means is permitted only with the approval of The approval portionthe ofwith any permitted articleonly photocopy by is of machine, reposting, this means or collective or other redistirbution NURC: CELEBRATING 50 YEARS OF InTErnATIONAL PARTNERSHIPS IN OcEAN RESEArcH AND OpERATIONS Oceanography , Volume 21, Number 2, a quarterly journal of The 21, Number 2, a quarterly , Volume The Interaction of Marine Mammals O ceanography ceanography S and Active Sonar The 2008 by Copyright ociety. By KENDRA RYAN Over the last 50 years, international FOUNDING OF SOLMAR environmental assessment procedures public concern regarding human impact From May 12–15, 1996, NURC (for- be implemented as soon as possible O ceanography ceanography O on the environment has increased merly known as SACLANT Undersea with a view to recommending suitable ceanography drastically. Specific to the maritime Research Centre, SACLANTCEN) mitigation and monitoring protocols. S domain, attention has more acutely conducted the Shallow Water Acoustic In addition, the panel determined that ociety. S ociety. ociety. A focused during the last ten years on the Classification (SWAC ’96) research additional research was needed to reproduction, systemmatic Republication, article for use and research. this copy in teaching to granted ll rights reserved. is Permission S temporal and spatial relationships of cruise using low- and mid-frequency determine biological and behavioral or Th e [email protected] to: correspondence all end marine mammals’ strandings to the use (600-Hz and 3-kHz, respectively) characteristics of marine mammals. The of active sonar. The NATO Undersea active sonars off the coast of Greece findings and recommendations of the Research Centre (NURC) has been at (SACLANT Undersea Research 1998 Bioacoustics Panel prompted the the forefront of research regarding the Centre, 1998). Concurrently, 12–13 creation of the SOLMAR program. interaction of marine mammals and Cuvier’s beaked whales (Ziphius active sonar. In 1999, NURC established cavirostris) stranded along the coast SOLMAR OBJECTIVES one of the first research programs in of Kyparissiakos Gulf, Greece. NURC (1999–2006) O the world to address this topic, the hosted a bioacoustics panel comprised The SOLMAR program was a multi- ceanography Sound Ocean Living Marine Resources of subject experts shortly after Frantzis national, multidisciplinary research (SOLMAR) program, now known as (1998) hypothesized an association project with the objective of developing S ociety, P ociety, the Marine Mammal Risk Mitigation between the SWAC experiment and the the tools and/or procedures with which O (MMRM) program. With the participa- stranding event. The panel concluded an experimenter can ensure there are no B ox 1931, Rockville,ox M tion of numerous international partners, that an acoustic link was neither clearly marine mammal risk mitigation policies, established nor eliminated as a direct or Lt. Kendra Ryan (USN) ([email protected]. procedures, and technologies were indirect cause of the May 1996 stranding int) was Marine Mammal Risk Mitigation implemented, and continue to be devel- (SACLANT Undersea Research Centre, Project Officer, NATO Undersea Research D 20849-1931, U oped, to minimize the potential impact 1998). Despite the nondefinitive conclu- Centre, La Spezia, Italy, from January 2007 on marine mammals. sion, the panel recommended that to May 2008. SA . 38 Oceanography Vol.21, No.2 Figure 1. Sirena ’99 (left) and Sirena ’00 (right) Sea WIFS chlorophyll a (mg m-3) in the upper layer, chlorophyll a maximum (mg m-3) with fin whale visual sightings in the middle layer, and the depth of the maximum values of chlorophyll a in the lower layer. SACLANT Undersea Research Centre, 2001 marine mammals near a sonar source marine mammal populations in the and ammonias), fluorescence, turbidity, prior to and during its use (D’Amico et Mediterranean Sea and environmental and phytoplankton (chlorophyll), were al., 2003b). At the inception of the pro- parameters in relationship to these gathered concurrently from an Italian gram, little was known about the regions population densities navy hydrographic vessel and from of high and low cetacean density within • Acoustic and visual tools to detect various other vessels provided by partner the areas where NURC experiments were cetaceans organizations. Sea surface temperature, conducted. The first tasks of the project To accomplish these last two objectives, surface currents, surface roughness, and were therefore to develop: a series of sea trials, entitled SIRENA, ocean color were collected in real time at • A network of scientists with knowl- were conducted. NURC using satellite remote sensing. edge of marine mammal distribution, behavior, bioacoustics, and sonars SIRENA SIRENA RESULTS • A database containing all documents The SOLMAR program conducted The SIRENA cruises provided a vast and data related to marine mammal SIRENA sea trials annually in the quantity of data that enabled scientists distribution, behavior, and associated Ligurian Sea from 1999 to 2003. to answer some of the primary questions bioacoustics information Bounded by Italy, mainland France, regarding Mediterranean Sea cetaceans • A risk mitigation instruction based and Corsica, the Ligurian Sea was and their habitat preferences. During on available knowledge that contained designated the first International Marine SIRENA ’99, a total of 869 individuals policy and protocols to ensure that Sanctuary in the Mediterranean Sea was observed during 146 marine mam- active acoustic research was planned and was the common habitat of eight mal sighting events (D’Amico et al., and performed in an environmen- cetacean species. The NATO research 2000). Analysis of the data from 1999 and tally sensitive manner (SACLANT vessel, R/V Alliance, was the primary those from SIRENA ’00 showed that the Undersea Research Centre, 2004) platform for conducting visual and fin whale (Balaenoptera physalus) and Upon completion of these tasks, the acoustic monitoring of cetaceans. sperm whale (Physeter macrocephalus) project shifted focus to development of: Oceanographic measurements, including generally preferred cold, deep, nutrient- • A database containing information on temperature, salinity, nutrients (silicates rich portions of the basin (Figure 1; Oceanography June 2008 39 SACLANT Undersea Research Centre, 2001) while the Cuvier’s beaked whales preferred a submarine canyon (the Genoa Canyon) where there is a frontal influence and steep bathymetry (D’Amico et al., 2003b). Also during SIRENA ’00, a sperm whale was tagged with a noninvasive digital recording device (Johnson and Tyack, 2003) to gather data regarding the whale’s diving behavior and vocalization activity. The data indicated that the aver- age depth of this sperm whale’s foraging dives was 900 m. At this foraging depth, the acoustic behavior of the sperm whale Figure 2. Three-dimensional track of a tagged sperm whale. Surface positions marked with an “x” indicate a visual sighting. Tyack and changed, and the data supported the Zimmer, 2002 hypothesis that sperm whales echolocate on prey at a constant horizontal layer (Zimmer et al., 2003). Such data advance knowledge of normal sperm whale behavior so that behavioral responses combined with visual and passive acous- application of digital recording devices to anthropogenic activities may be tic methods to enable three-dimensional to sperm whales continued, and opera- better understood. tracking of the whale’s movements and tions included exploring the feasibility The objectives of the SIRENA ’01 foraging events (Figure 2; Tyack and of a whale-finder sonar. Using defined sea trial were to continue collection Zimmer, 2002). Analysis of this informa- protocols, the feasibility test involved of oceanographic and species data for tion supported conclusions regarding controlled transmission of an active population of the developing database sperm whale habitat preference that were sound source in the vicinity of tagged and to evaluate techniques for effective derived from previous SIRENA cruise animals. Analysis of the passive acoustic risk mitigation (SACLANT Undersea data (SACLANT Undersea Research data confirmed that sperm whales produce multipulse clicks centered around 15 kHz, with source levels of more than 230 dB re 1µPa @ 1 m, and (NURC) has been at the forefront of a narrow, forward-oriented sonar beam (Møhl et al., 2003; Zimmer et al., 2005b). research regarding the interaction of Additionally, in 2002, the SIRENA sea marine mammals and active sonar. trial focused on determining the specific habitat of the Cuvier’s beaked whale. Based on Cuvier’s sighting data from previous years, a survey of the Genoa Research Centre, 2000). During the Centre, 2002). In addition, visual sight- Canyon (~10,600 km2) was undertaken. cruise, tag data (e.g., vocalizations, ings and acoustic data from a towed Analysis of the oceanographic and pres- dive depths, and whale orientation) array contributed to the population of ence data determined that all Cuvier’s transmitted from a digital recording the marine-mammal-sighting database. sightings were in water depths greater device attached to a sperm whale were During SIRENA ’02 and ’03, the than 1000 m. These areas may provide a 40 Oceanography Vol.21, No.2 preferential habitat (one with an abun- dant food source) due to the oceano- graphic conditions that