Animal Oceanographers

larryo: Hello!

kochevar: Good morning Larry!

larryo: Good morning. How's the weather, um, where ever you are?

kochevar: I'm at the Hopkins Marine Station in Pacific Grove, CA - about 5 hours north of Los Angeles, and 2 hours south of San Francisco. We had a big rainstorm come through last night, so it's a bit drippy out!

larryo: I think we're about to get that storm here in New Mexico. Sky in socked in, and snow is in the forecast. Brrr. Have you figured out how to expand the chat window, btw?

kochevar: I have! I actually made it "pop out" so I can have other things going on - on my desktop. (Not that I'm multi-tasking or anything!)

larryo: Oh good. That's one of the nice things about chat interviews, you can actually do other things at the same time :) 10:44 AM So what I'm doing is putting together a package of content on how we learn about and monitor the oceans. I wanted to talk to you about the more specific role animals have in helping us do this.

kochevar: Great!

larryo: Last I recall, which is a few years back, there was an amazing array of animals carrying sensors out there! Is that still the case?

kochevar: That is correct. In our "Tagging of Pacific Predators" program, which is part of the global Census of Marine Life, we are tagging and tracking 23 species of open ocean animals - including sharks, whales, seals, sea lions, seabirds, sea turtles and even squid!

larryo: Now these sensors are of all types too, right? And their objectives vary a lot?

kochevar: There is a basic set of sensors -- depth, temperature and light -- that are found on virtually all of the tags. Then some tags carry additional sensors. These include devices for learning more about the physiology of the animal - like internal temperature sensors, heart rate sensors, etc.; and others are for monitoring external conditions - like salinity.

larryo: So who is deploying these tags, marine biologists mostly interested in their study species?

kochevar: They are marine biologists, along with their graduate students, postdocs, technicians, etc. And you're right - typically individual labs focus on one group of animals. In our lab, for example, we work mostly with sharks and fishes like tuna and billfish. Other labs focus on whales or seals and sea lions or turtles. 10:54 AM One of the thing that makes TOPP really cool, though, is that we brought together over 100 scientists, from 7 diffrent nations, to collaborate on this one big project.

larryo: That's pretty huge.

kochevar: And that group included not only marine biologists - but also engineers and oceanographers. 10:55 AM It has been a VERY big project -- which began 10 years ago!

larryo: Here's a hard question: Can you think of a top five discoveries that have been made over those years from this tagging?

kochevar: Let's see...there have been lots of cool discoveries, so I won't put them in any particular order... 10:58 AM We now know that salmon sharks, which we tag in the Gulf of Alaska, swim all the way down near Hawaii during their yearly migration. 10:59 AM White sharks tagged along the coast of northern California also visit Hawaii - or congregate in a "mystery spot" about halfway between Baja and Hawaii, which we've come to call the "White Shark Cafe."

larryo: Hah! Wow.

kochevar: Leatherback sea turtles from Costa Rica swim south past the Galapagos Islands - and then fan out through the South Pacific - sometimes being gone for 2-3 years at a time! There are more species - specific fun facts - but perhaps the even more significant discoveries have occurred when we look at combined datasets.

larryo: ahah! That's a whole new level...

kochevar: There we can begin to see "ocean hot spots," where lots of animals spend a lot of time. Using this approach, we begin to see how rich the ecosystem is off the coast of North America - from San Francisco all the way south to the tip of Mexico's Baja Peninsula. 11:03 AM When we overlay the tracks with ocenography data, we can also begin to understand how vital the "transition zone" is. This is a broad swath of ocean, going from North America all the way to Asia - about halfway between Hawaii to the south and Alaska to the north. 11:04 AM This is where cold, polar water mixes with warmer, temperate water -- and lots of animals use this zone as a highway across the Pacific!

larryo: How is it a highway? I'm not understanding.

kochevar: I'll give you an example. We've tagged many Pacific bluefin tunas in the area of northern Mexico. Some of these tunas have crossed the entire Pacific to Japan and back. And the path they took was right along this corridor. We also see it being used by elephant seals, leatherback sea turtles, and Laysan albatross in their foraging flights.

larryo: What's there that makes it so attractive? More food? Favorable currents?

kochevar: It's almost certainly a combination of those things. For some animals, they appear to be focusing on the food available there. (Productivity is often high where you find cold, nutrient-rich water coming in contact with warmer water masses.) For others, they seem to be concerned less about eating and more about just getting where they are going -- in which cases it could be that the boundary between water masses acts as some sort of cue to keep them going in the right direction.

larryo: Ah. A navigation aide. That's neat.

kochevar: That's totally just a guess -- but one mystery has always been how these animals find their way across such a vast ocean!

larryo: Sounds like a nice hypothesis. How in the world to test it? Is all the environmental data also being brought together to look at the oceans as well? Can it be combined with data from other sorts of mechanical sensors?

kochevar: At the end of the day, you'd really have to be able to answer the question, "Why is the animal making the choices it is making?" and we may never know the real answers. So we are left looking at all the things we can measure -- and yes, that means combining data from the tags with data from buoys, gliders and even satellites, to see if we can correlate the behavior we observe with physical conditions we can detect with all these various devices.

larryo: Is the animal tracking data helping to identify any trends in the oceans, or is it still too short a record?

kochevar: It's a pretty short baseline - just 10 years, which isn't really long enough to pick up longer-term trends. However, our dataset did span the major El Nino event that happened a few years back. What's cool about that is that we saw all kinds of behaviors that year that were different from every other year of the study! So we may have some clues about how animal behavior could change under a very different set of environmental conditions -- possibly more like what we would see in the warmer ocean of the future.

larryo: That is very intriguing. Almost like Nature set up a nice experiment for you.

kochevar: Exactly!

larryo: Does any of this fit into fisheries matters too. I know bluefin tuna were in the news last week because of concerns they have not been managed well.

kochevar: I'm glad you asked about that! The person who runs our lab - 11:24 AM Dr. Barbara Block - has been studying bluefin tunas around the world for about 14 years now.

larryo: cool

kochevar: Her studies, particularly in the Atlantic, have played a crucial role in helping us to understand the dynamics of their populations. 11:26 AM It turns out to be a bit complicated - with one population breeding in the Mediterranean, and another in the Gulf of Mexico. Both stocks mix on the feeding grounds, where they are commercially harvested, but they are, in fact, distinct groups. With this knowledge, resource managers can now do a much more effective job of constructing management plans that take into account the basic biology and life history of these different populations.

larryo: That's also neat evolutionarily -- that they don't mix.

kochevar: In general, we hope that all our work will play this role: To help define the critical habitats for these animals, so resource managers will be in a better position to make informed decisions about where and when to protect them.

larryo: So what's next on the tagging horizon. Any new technologies on the verge, or projects?

kochevar: There are always interesting technologies in the works. For our current projects, we've really tried to focus on getting lots of tags out - but using versions that have a long, proven track record. But there is work being done to take advantage of the ever-growing GPS satellite network for geolocation, improving battery life and performance and reducing size. There is also some neat work being done with tags that use "micro-accelerometers" - like they have in Wii controllers -- to measure subtle movements, etc., in an animal carrying such a tag.

larryo: So sounds like plenty of neat stuff ahead. Really neat stuff. One last question before we go (our time is about up): You have any favorite animal for tagging, and if so, why?

kochevar: Well, I have to be honest here. I don't get to spend much time in the field. But last summer I got to go to the 50th annual Hawaiian International Billfish Tournament, where we launched the Great Marlin Race (www.greatmarlinrace.org). Because I actually got to be part of the process, I'll say my favorite right now is the Pacific blue marlin! 11:40 AM We put out 10 tags on marlin, and only three have come up so far -- one of which was 2,525 miles away from where it started! We expect the rest of the tags to come off in the next 6 weeks or so -- and the one that travels the farthest wins its sponsoring team free entry into the 2010 tournament! Should be lots of fun to see who wins -- and we get great data in the process!

larryo: Sounds like a lot of fun! And loaded with "gee whiz" value as well. I imagine the students love this.

kochevar: We're working with some teachers right now to grow our classroom outreach programs. There's always more to do!

larryo: Well thanks for your time. I really appreciate it. I think our audience will get a inkling for the stuff you guys do, which is what I was after.

kochevar: Great! Thanks for the opportunity - and please let me know if there's anything else you need!

larryo: Will do. Cheers!