Meet Lisa Munger, Marine Ecologist
Interview: April, 2002

Local residents in Nelson Lagoon, Alaska found a strange object washed up on a remote Bering Sea beach after a big storm in January, 2002. Luckily, a note on the side said finders should call Scripps Institution of Oceanography in San Diego and collect a reward. Students from Nelson Lagoon School and their principal, Mr. Concilus, were on it! (See Videotaped interview by the students.) It turned out to be a lost whale study/tracking device with a sonar probe and computer for recording whales as they migrate. Designed to lay on the sea bottom about 285 feet down, it was deployed in 2000. When it was time for the device to "come home," the scientists sent an electronic signal to release ballast, and planned to collect the device by ship. PhD student Lisa Munger was sent to Alaska in 2001 to retrieve the thing -- called an Acoustic Recording Package -- couldn't find it. In March 2002, she came back to extract the computer hard drives and retrieve the acoustical data from the lost-now-found. Here's what Lisa told Journey North:

Lisa Munger explains the ARP to students at Nelson Lagoon School.
The lucky sixth graders were involved as she took it apart to access the drives.

Two round floats suspend the hydraphone about 15 or 20 feet above the ocean bottom.

Black tubes on the bottom house computer equipment, and
two SCSI hard drives to record data
.

Lisa extracts the computer hard drives to retrieve the acoustical data. Photos John Concilus

Q. Where are you studying for your PhD?
A. I am a first-year Ph.D. student at the Scripps Institution of Oceanography (which is part of UC San Diego). I'm in the Biological Oceanography department. (When you say marine biology here, people think mostly of molecular biochemistry type stuff.) I guess you could call me a marine ecologist. My advisor is Dr. John Hildebrand, whose background is mainly in geophysics. Recently, interest and funding have increased for cetacean acoustics research, and Dr. Hildebrand has several other students and research associates working on various whale projects, such as blue whales off the California coast and whales in the Antarctic. We collaborate with many other scientists and agencies on all of our projects.

Q. What is your focus or specialty?
A. My project, right whales in the northeastern Pacific, will probably be the subject of my dissertation. We're working with a few government agencies under NOAA (National Marine Mammal Laboratory, National Marine Fisheries Service, and the Pacific Marine Environmental Laboratory), Oregon State University, and Mark McDonald of Whale Acoustics (check out his website at whaleacoustics.com). I'm sorry to neglect your animal of interest, but as you know, gray whales exist in pretty good numbers in the Pacific, so they're not as high a priority as right whales from a government funding perspective.

Q. Can you tell us how many right whales are in the northern Pacific?
A. There are probably two populations in the north Pacific; one off Japan and the one we're interested in, known mainly in the Bering Sea from visual surveys (aerial and ship-based). Based on these surveys and photo-id matches, this population numbers pretty low (probably in the tens), and no females have been identified in the small number of genetic samples (only 5 or so).

Q. What information on right whales are you looking for?
A
. Our first and foremost question right now is: when are the right whales in the Bering Sea? We'd like to know more about the abundance, demographics, distribution, and timing of arrival and departure of right whales in the Bering Sea (basically everything about them!). Visual surveys can only tell us certain things about the whales, and can't be done constantly, so we have large gaps in our knowledge. Right now we have almost no idea how long the right whales are in the Bering Sea and where they go otherwise. There have been isolated sightings in Hawaii, the Channel Islands, and off of Kodiak island, but these don't give us a clear picture of migration or potential calving grounds.

Q. What techniques are you using to study right whales?
A.
We are trying to use acoustic methods to monitor the right whales and answer some questions that are hard to answer with visual methods.

Q. Describe the instruments.
A.
The Acoustic Recording Packages (ARP) have one job. Recording sound is all they do-- no photographs, no data on temperature, nothing else. Acoustic Recording Packages

  • are anchored on the bottom (supposed to be, anyway!),
  • run on batteries,
  • sample at rate of 500 Hz (which means continuously for our purposes),
  • and record the data to disks.

Q. What kind of recordings are made by an ARP?
A.
An ARP only record sounds between 0 and 250 Hz (relatively low frequencies), at a range of up to 10-20 miles (depending on ocean conditions, weather, etc). The recordings are not like on a tape or CD player; they're in a binary data format, which means we need a computer program to run the data by so we can look for whale noises.

Q. Did you say you LOOK for whale noises?
A.
That's right — look, not listen. I use software to graphically present the data in a frequency-versus-time plot. This allows us (me) to visually scroll through the data much quicker than listening to it in real time.

Q. Can you tell different whale species apart on the recordings?
A
. Whale species each "speak different languages", that is they have different call types, but sometimes humpbacks and right whale calls can be hard to distinguish from each other (especially as the frequency range of our instruments is so limited). If I see something that looks like a right whale call, then I listen to it also; this helps somewhat. Much of the data is just background noise, storms, ships, etc.

Q. Where are your Acoustic Research Packages located?
A.
In October 2000, colleagues deployed four of these instruments in an area of the Bering Sea where right whales have been sighted every summer since 1997, around 57 degrees North and 163-165 degrees West. (That's about 70-80 miles offshore from Nelson Lagoon). We went out in 2001 and recovered two instruments out of four; we also deployed two new instruments in the same area.

Q. What are some difficulties in your work?
A.
Each instrument we successfully recovered holds about 7 months' worth of recorded data, from October 2000 to April/early May 2001. This is not a complete time frame to monitor migration, as it leaves out the summer months when right whales could be arriving or departing. The process of scrolling through the data, even visually, is still time-consuming, and I'm busy with classes so haven't made much progress. So far, the data have only been examined on one instrument for just the first month of operation (October 2000). I have seen loads of fin whale calls and many humpbacks throughout the month, and a few right whales in the first couple weeks of that month. Lots more work needs to be done, and we're trying to speed up the process of scrolling through data (we're using a computer program that can automatically detect certain call types). Plus, this summer (2002) we hope to recover two more instruments, with batteries that lasted longer than the first prototypes, so we'll have more than double the data we have now.

Q. Do you expect to always get your Acoustic Research Packages back?
A.
We are concerned about our instrument recovery rate, although the one found in Nelson Lagoon brings us up to 75%, which is much better than our previous 50%. The area where we deployed the instruments is pretty shallow (around 80 m = 250 feet), so strong storms or currents may shift or damage the instruments. The deployment area also corresponds to a seasonal crabbing closure area, but I'm told that fishermen still occasionally drag there, so it's possible our instrument was dragged up or damaged, enabling it to drift away.

Q. Have any gray whale noises shown up on your recordings?
A
. No gray whales — I think the instruments might be too far offshore to pick them up, and the timing is probably off too.

Q. In looking at the data, has anything surprised you?
A
. A couple of interesting things have arisen from looking at the data; one is that the right whales are up there at least into October, which is later than previously thought, and the second is that humpback whales appear to sing in winter and not just during the summer breeding season.

Q. What would you MOST like students to know?
A
. There are two points I'd like to impart to kids. One is that science is a cooperative process. Not only are we working with researchers from different agencies and with different specializations, but we also cooperate with fishermen, policy makers, and the public (such as residents of Nelson Lagoon or visitors to your Web site). Only in this way can science contribute something meaningful and lasting to the "real world."

Another point is that there are still MANY unanswered, exciting questions out there. I've heard it said that we know more about outer space than we do about our own oceans. Even big questions, like where do the right whales go in winter, are still a mystery. There's unlimited potential in marine sciences (and other sciences too) to make a living, and it's so fun and worthwhile!

Cheers,

Lisa Munger
Scripps Institution of Oceanography
La Jolla, CA 92037-0205