In this section visiting scientists who are working aboard Odyssey will describe the work they are doing. Although this is a technical report, in many cases contributions from such scientists will be in the form of informal reports. By this means visitors to this website can get different views of the work we do.
- Daniel M. Palacios, College of Oceanic and Atmospheric Sciences, Oregon State University, Corvallis, Oregon, USA
- Karin A. Forney, Southwest Fisheries Science Center, NMFS, La Jolla, California, USA
- Lisa S. Baraff, National Marine Mammal Laboratory, NMFS, Seattle, Washington, USA
- Rebecca A. Clark, Ocean Alliance, Lincoln, Massachusetts, USA
Media, Education and Communication Team:
- Genevieve Johnson and Christopher Johnson, Ocean Alliance, Lincoln, Massachusetts, USA
Puerto Ayora, Isla Santa Cruz,
Islas Galápagos, Ecuador
26 April 2000
The Ocean Alliance initiated research activities on cetaceans in waters of the Galápagos Marine Reserve in April 2000, aboard the research vessel Odyssey. The Odyssey arrived in Puerto Ayora on 2 April 2000, after a 16-day transit from San Diego, California, USA. The investigation has the following components:
- Toxicology studies on sperm whales. Collaborators: John Stegeman and Michael Moore, Woods Hole Oceanographic Institution.
- Genetic studies on sperm whales. Collaborators: Sarah Mesnick, Southwest Fisheries Science Center, and Bill Amos, Cambridge University.
- Photo-identification studies on sperm whales. Collaborator: Hal Whitehead, Dalhousie University.
- Acoustic studies on sperm whales. Collaborators: Chris Clark, Cornell University, and Jonathan Gordon and Doug Gillespie, International Fund for Animal Welfare.
- Cetacean distribution, abundance and relationship to oceanographic processes around the Galápagos. Collaborator: Daniel Palacios, Oregon State University.
In addition, the Ocean Alliance runs a media, education, and communication program from aboard the R/V Odyssey called "A Voice from the Sea". The mission of this program is to bring the results of the scientific projects to the general public via a network-based, interactive web site, with the ultimate objective of educating the public and increasing marine conservation awareness worldwide.
These activities are authorized by the Galápagos National Park (Proyecto No. PC-32-00 of 11 February 2000, with Alcance a la autorizacion original of 13 March 2000) and by the Dirección General de la Marina Mercante y del Litoral (Autógrafo: Acuerdo No. 018/00 of 27 March 2000).
The first cruise took place between 22 April 2000, with Daniel Palacios as chief scientist. The primary objective of the cruise was to conduct a survey of cetacean abundance and distribution in relation to oceanographic processes on the western side of the archipelago. (Hereafter this survey is referred to as "GalCet2K"). In addition, some effort was spent working with sperm whales on the toxicology, genetic, photo-identification, and acoustic studies. These activities were covered by the education, media, and communication staff, as reported below.
A survey for cetacean abundance with concurrent oceanographic sampling took place between April 5-19, with the goal of characterizing cetacean abundance and distribution with respect to a gradient in temperature and biological productivity. The area selected for the survey was a 3ºx2º box (approximately 74,166 km2) designed to encompass the warm, oligotrophic waters to the north of the Equatorial Front (located at ~1ºN) as well as the cool, productive waters to the west of the islands, where the Equatorial Undercurrent upwells. The original boundaries of this box were set to extend from 92-94ºW longitude and 2ºN-1ºS latitude, based on the long-term sea-surface temperature climatology. Five days into the survey, however, after examining near-real-time satellite imagery of ocean color and temperature sent by Gene Feldman at NASA it was decided to move the meridional boundaries of the box to 91º20'-93º20'W, to best cover the features of interest. Survey tracklines followed a north-south zig-zag pattern. There were 12 trackline segments, each one being 90 nautical miles (n.mi.) long (~167 km), for a total of 1,080 n.mi. (~2,000 km). Figure 1 illustrates the final trackline layout and the tracklines actually surveyed. An image of ocean color for 30 March 2000 is included in Figure 2, to show the distribution of surface phytoplankton in the study area.
Cetacean surveying was conducted from an observation platform located 5.6 m above sea level, with a maximum sighting distance to the horizon of 4.56 n.mi. (8.45 km). Surveying effort was conducted at a nominal cruising speed of 8.5 knots, employing standard line-transect techniques. Experienced cetacean observers maintained a visual watch during daylight hours (0600-1800 h), using 7x binoculars to scan the area 180º forward of the ship and out to the horizon. An observer team of four people rotated every hour through three operations: port observer, starboard observer, and data recorder. For each cetacean sighting, bearing (angle from the trackline, measured with an azimuth ring) and distance (calculated using the calibrated reticule scale in the binoculars) were recorded. Weather conditions related to sightability (sea state, swell, meteorological conditions) and navigation data were also recorded. Cetacean sightings within one nautical mile from the trackline were approached to obtain species identification and to estimate school size. All data were entered into a laptop computer running the software WinCruz v. 5.2.1. Data on seabirds, turtles and sharks seen at the surface were also regularly collected as part of the survey protocol.
The structure of water column properties (temperature, salinity, density and phytoplankton standing stock) along the track was measured with CTD/fluorometry casts. A total of 32 casts were completed, as shown in Figure 1. Sea-surface temperature along the track was recorded at a sampling rate of one reading every eight minutes. Biological samples were opportunistically collected at the surface from dead squid and fish. These samples have been labeled and preserved and will be useful in studies of potential prey for cetaceans. A more detailed report of the results of GalCet2K will be submitted at a later date.
Sperm whale work. Although sperm whales were occasionally observed during the GalCet2K survey, dedicated effort was not conducted until after the end of the survey. Two days (20-21 April) were entirely spent on sperm whale visual and acoustic monitoring (using a towed hydrophone array and the software Rainbow Click). In total, seven acoustic transects were performed, during which 13 acoustic contacts with sperm whales were recorded. Eight sperm whale sightings were made during daylight hours, on 2, 17, 18, 19, 20 and 21 April. Four biopsy samples were collected on 20 April. Figure 3 shows the distribution of the acoustic transects, acoustic contacts, sightings, and biopsy sampling locations. Photographs of individuals identified with a digital camera are presented in Figures 4 and 5.
The Galápagos National Park and the Dirección General de la Marina Mercante y del Litoral authorized our research activities in the waters of the Galápagos Archipelago. Poly Robayo, Jenni Thompson and Edwin Yanez of the Charles Darwin Research Station provided invaluable logistic support. The port captains of Santa Cruz and Seymour islands kindly processed our zarpe paperwork. TAME airlines provided discounted air travel between the Galápagos and continental Ecuador.
We thank the rest of crew of the R/V Odyssey: Bob Wallace, Alison Walker and Daniel McBride for ensuring a successful operation. This cruise was funded by the Oregon State University Marine Mammal Endowment Fund (through Bruce Mate), Cetacean Society International (through Bill Rossiter) and the Ocean Alliance (through Iain Kerr). The following individuals kindly loaned vital equipment: Scott Pegau (CTD instrument), Paul Fiedler and Valerie Philbrick (fluorometer), Tim Gerrodette (binoculars), Jay Barlow (azimuth rings). Robert Holland and Sarah Mesnick ensured we had a running version of the WinCruz software for collecting the line-transect data. Gene Feldman provided near-real time ocean color and sea-surface temperature satellite imagery that enhanced our trackline design.
Listen to Daniel Palacios discuss the results of this line-transect survey