Making noise about noise
Reporter Robert Santos covered the issue of underwater noise pollution in the oceans on KOMO4 TV yesterday. Thanks to referrals from Fred Felleman and Kelly Balcomb-Bartok, I was contacted to provide a connection between the bioacoustics of our local killer whales and the conference of the UN Environment Program in Rome this week that is considering a resolution of member countries to recognize and address ocean noise pollution.
Fred’s copy of the PI article that sparked Robert’s interest.
Summer is almost over, but im finally getting around to editing that final paper a bit more, figure i’d get some these things done before I go start my crazy senior year. Editing also led me to reminiscing about beam reach, and looking at the videos.
And funny too how I still ended up doing a lit bit of sound work this summer at the zoo- been helping develop a behavioral monitoring program at Brookfield Zoo, and with that you need to collect data on different variables that might effect that behavioral, so hence we’ve been measuring sound levels around the park. Not recording actually, they are called docimeters, and they measure the average dB level each minute, as well as measure the peak sound level of each minute. The devices we use are acutally designed for workers at their jobs the meaure the amount of sound exposure in their work place- here we are using them by hanging them up in trees in fake bird houses, and the most fun one is up in the ceiling of the monkey house- the first time we put it up there the baboons were screaming like crazy before the visitors came in, and as it eerily echoed up to us as we looked down from the opening above them, I have a vision of Dante’s inferno…
Anyways, the even more fun(!) part is that we get to analyze the data and work on making a database (i.e. me stumbling through access)- and what little we have looked at so far we haven’t found too much of any effect on behavior- but then again the averages we get aren’t changing much- but more analyzing to come for the final presentation in a few weeks, so maybe we’ll get some different results. But then again, no effect isnt a bad thing at all- im pretty sure most zoo animals get used to all the noise, especially with the constant construction here.
So no hydrophones, but hey at least some acoustics 🙂 i got to ask smart questions like if they are calibrated or if they can measure frequency.
Other than that, been working on my own project investigating how the placement of an observer effects an animal’s behavior, but I also found out that zoo keepers bring special guests to feed the animals im looking at, so that kinda skewed my results a bit – but nevertheless I’m still going on with it, and at the same time I’m now trying to help out the female Grevy Zebra get pregnant- I hope I can get that one to work out.
Well thats all for now, i suppose this is a bit random, but I thought beam reachers would be happy to learn about some zoo acoustics
I’ve asked a lot of people why the southern resident killer whales spend so much of their time swimming up and down the west side of San Juan Island. Most folks suggest that they’re here because the fish are here. Ask long-time population surveyor Ken Balcomb of the Center for Whale Research what motivates the orcas to be resident and you’ll get the succinct synopsis he passes on from First Nations elders: “No fish; no blackfish.” Yet I’m amazed at how little is known about what fish are present at any particular time in this part of the San Juan Islands, not to mention the Salish Sea in general.
From April through October the three resident pods are most frequently found along this coastline, the eastern side of Haro Strait. Their most common dance is known as the “west side shuffle” in which the pod(s) travel back and forth from somewhere near Eagle Point in the south to Henry Island in the north, often pausing to forage, socialize, or mill, but rarely resting. I’ve yet to hear of the residents transiting the same body of water on the Canadian (west) side (though transients often do), and I doubt it’s because the Canadians don’t treat their sewage as much as we do.
The orcas often make intermittent excursions further afield. They loop out to visit Hein and Middle banks offshore. They zip west past Race Rocks for a listen along south Vancouver Island. Or they voyage northward to the Fraser River delta before circumnavigating the archipelago via Rosario Strait. But they always seem to return to the west side — the core of their summertime range.
There might be non-fishy reasons orcas might like the west side of San Juan Island. Perhaps they appreciate the great acoustics along the steep unsedimented submarine coastline. Maybe they have a rubbing “beach” like the Northern residents, but hidden deep off of False Bay. Or maybe the west side is just a cross-roads: a familiar pathway that you take whether you’re headed out to the Pacific and the Elwha, up to the Fraser or Nooksack, or down to the Skagit and Puget Sound.
How could we demonstrate that prey availability is the factor that focuses the southern residents attention on the west side of San Juan Island? What kind of fish are they eating? Why and when are which fish available; and implicitly, how do the killer whales navigate the complex distribution of salmon in the Salish Sea? More practically, which (endangered?) fish population segments should we be saving for our endangered whales?
Our primary approach to answering such questions is to discern what the southern residents eat and then observe the behavior of those prey items along the west side. Secondarily we gather basic information about distributions of potential prey in case the prey sampling studies have biases that lead us to overlook important food sources.
The growing body of information about what orcas eat is the best evidence we have of what prey they are after. The current scientific consensus — from analysis of scraps, underwater video, the rare stranded whale’s stomach contents, and poop — is that southern resident killer whales really like Chinook salmon. In the best synopses I’ve seen (of data predominantly from May-October) Ford et al (1998) and Ford and Ellis (2006) suggest that Chinook are preferred at all times except perhaps in the late fall when chum salmon return to many local rivers (and the residents, especially J pod, begin making southward forays into Puget Sound). There also hints that bottom fish such as halibut, lingcod, and dover sole are taken occasionally.
A big problem is that not many people are doing a good job of monitoring what fish are present in the Salish Sea (as opposed to Northwest rivers) generally, and in Haro Strait specifically. A major goal of the spring 2008 Beam Reach program was to test new acoustic tools that could help us fill the observational gap. I’ll post separate articles with detailed results this summer, but for now here is a synopsis of the two new tools we tested:
First, through a new partnership with Seattle-based Biosonics, we used a 200 kHz scientific echosounder to measure fish densities in Haro Strait. Mounted on a pole and pointed straight downward, the echosounder projected sound in a 6-degree-wide beam and received the echoes from fish, plankton, and the sea floor. With real-time display and data logging, we were able to survey fish distributions in Haro Strait (and map bathymetry and bottom type) both in the presence of orcas and when they weren’t around. Thanks to the generous donation of equipment and software, we were able to observe remarkably complex distributions of fish along the west side and to quantify fish densities in a preliminary suite of foraging locations.
Another active acoustic technology we tested was an acoustic tag that can transmit a depth measurement from inside a fish. We purchased two tags from Vemco and guided by instructor Eric Eisenhardt, implanted them surgically in lingcod near Lime Kiln State Park. With the mobile tracking unit that Vemco kindly provided for free, we were able to monitor the two young fish for about a month and learned they make only occasional depth excursions while remaining in the area where they were caught and released. The fish stayed near 18 and 40 meters depth throughout our study, suggesting that when killer whales make deep dives (>100 meters) to the local bottom (Baird, 2003) are probably not related to foraging for young lingcod on the west side of San Juan Island in the spring.
Baird, Robin W., M. Bradley Hanson, Erin E. Ashe, Michael R. Heithaus, and Gregory J. Marshall (1993) STUDIES OF FORAGING IN “SOUTHERN RESIDENT” KILLER WHALES DURING JULY 2002: DIVE DEPTHS, BURSTS IN SPEED, AND THE USE OF A “CRITTERCAM” SYSTEM FOR EXAMINING SUB-SURFACE BEHAVIOR. Report to the National Marine Fisheries Service, National Marine Mammal Laboratory, 7600 Sand Point Way N.E., Building 4, Seattle, WA, 98250 USA.
Ford, John K. B., Graeme M. Ellis, Lance G. Barrett-Lennard, Alexandra B. Morton, Rod S. Palm, and Kenneth C. Balcomb III (1998) Dietary specialization in two sympatric populations of killer whales (Orcinus orca) in coastal British Columbia and adjacent waters. Can. J. Zool. 76(8): 1456–1471 | doi:10.1139/cjz-76-8-1456.
Ford, John K. B., Graeme M. Ellis (2006) Selective foraging by fish-eating killer whales Orcinus orca in British Columbia. Marine Ecological Progress Series, 316:185-199.
I’ve been spending a large part of my time doing analysis trying to localize calls in Ishmael. Since I never had a situation where the entire group was social. I have to localize the calls from each social period to see if they came from the social group or not. The way you do that is by opening the file in a program called Ishmael, imputing your hydrophone data, selecting a call, and pressing localize. When you do that Ishmael looks at the four channels that were recorded and calculates the difference in time it took for the sound to reach the four hydrophones. It can then use this to calculate the location of the call.
Unfortunately Ishmael is not perfect and neither are our recording conditions. Since the ocean is a noisy environment with lots of background noise there are times that it can’t distinguish above the background noise and will give you some strange answer that sometimes invloves the animal being millions of miles away. Also, if a call is made directly in front or behind the array it can’t localize well because the sound waves are coming straight on. Because of this I have a lot calls which can’t be localized well if at all.
All in all this is doing nothing to make the frantic last week of analysis and paper writing easier. That said, it is slowly bit by bit getting done and I feel good that I will be able to pull everything together and be able to have a good presentation ready come Saturday morning.
Thanks to the Spring ’08 class for all of the great posts! I’ve enjoyed following your adventure and I have to admit that I’m a little sad that you’re almost done already! I’m so glad that the whales finally cooperated …if a little too much toward the end. Laura and Dominique’s last posts remind me of the frenzy of that last week. Hang in there as you analyze data and work on your presentations and papers (feel free to contact me if I can help you out). Those last few days are so full of exhaustion and excitement, sadness to leave and anticipation for the journey home. Just remember to take a deep breath every now and then and soak in the experience. You all have interesting projects and I wish I could catch those presentations! I look forward to your papers. Best wishes this week and on Saturday!
Well, I never thought I would say this in my life, but….I hope the whales don’t come around today. I know, I know, who do I think I am, have I gone insane, etc. BUT THERE IS SO MUCH DATA TO ANALYZE!!! All I’m asking for is one day to catch up on all this data, first because there just won’t be enough time in the last week to analyze everything I’ve got, and second because it would be good to know if something isn’t working, or needs to be adjusted. Also to see if the data so far indicates whether TTS might be occurring or not-I really want to know!
Though data is beginning to pile up, quickly, the process isn’t going nearly as smoothly as I thought, or had hoped. I guess that’s the point of this program: a little reality kick on how research on wild animals….wild endangered animals, goes. The reality of working with these animals is that you work with what you’ve got. Meaning that I unfortunately have to compare amplitudes of S1 calls from different days instead of the same before/after exposure periods of the same ship, exposure period end is determined on a per case basis instead of a regimented, consistent stopping point applicable to each session, etc. However, with some slight detours from what I had hoped to do, I am still getting valuable data which will give me something to say in the end, one way or another. Below is a spectrogram of an S1 call taken from J-pod on 5-15-08:
Alas…it looks like J-pod stuck around and we’re off to go find them. Definitely excited but a slight bit of anxiety is starting to set in!
Our time at sea went from one end of the spectrum to the other. Our first two weeks we had no whales and the last couple weeks we couldn’t get away from the whales. That combined with our sailing curriculum, software problems, and general life on the boat made for some long days. We did have some chances to relax with episodes of the flight of the conchords courtesy of lindsay as well as a copy of the life aquatic courtesy of the staff.
We were also supposed to have some time off to go on a camping trip friday night on doe island. However, what they say about the best laid plans of mice and men is true. After making smores and singing around the campfire things went downhill rapidly. When I say things I mean me and when I say downhill I mean off the side of a cliff. As you can probably guess by the fact I am now blogging about it I survivied. Falling 25 feet down a cliff has left me with many painful cuts and bruises, some very interesting memories, and a new sense of the bigger picture. Although I was very lucky not to suffer any serious injuries (I was even able to climb back up the cliff) it could easily have been much worse. I do want to take a chance to thank everyone who made sure I was alright that night.
Now I have to turn my beat up body to the task of analyzing all my data and trying to draw some conclusions from them. Although I did not get as many socializing events as I would have hoped for, I certainly got more than enough to keep me busy. As much as my body would probably like a rest, science waits for no one and I have lots of whale calls to keep me company as I heal. That said I should get back to work.
jeez you’d think after going to a college with 10 week terms I’d be used to chugging along through the final crunch, but I guess not! the work’s definately cut out for us this week, but it will get done … … … … its the getting done part thats the toughie…
the last week on water was an interesting one- who knew that we’d almost wish the whales would give us a break some time so we could analyze some data, or at least in my case wish there were absolutely NO marine mammals around so I could do my light bulb experiments- its quite funny. In total we ended up having 11 days with the whales- not bad for having no days for our first two weeks. And the amount of click day is ENDLESS….I wonder how many clicks total were recorded – I bet like 50,000 at least- what an excellant sample size that could be! (haha, yes note the “could” be). I ended up getting my other desperately needed spreading loss data- because of a certain seal (I lets call him Pesky Pete) I couldn’t do my experiment in Salmon bank, but found some shallow and seal-free waters in Griffin Bay before we headed into FHL for our one last time…
we didn’t get to sail too much our last week 🙁 but I did get a few chances to sail the Cyprid, which I quite enjoyed, except the wind liked to die-off in rapid bursts and then gust for a few moments while I was in there. My hand-made anemone turned out pretty cool, in a very un-planned way which made it look like a realistic anemone at low tide (the big squishy ones)- I hope the Beach watchers like it (and i also hope it doesn’t get stuck to anything, it’s basically made out of glue), the tentacles actually come in and out!
besides the data collection (and awesome photos of breaches, tail slaps, J1, and yes MORE dork) we had nights of flight of the conchords, excellent food, analyzing data, analyzing problems in our analyzing programs, re-analyzing data after figuring out what we did wrong in our analyzer programs, and cliff diving- and we made it out alive! I also flew Val’s kite again off the Gato Verde, which also almost got lost at sea and it’s tail stuck in the prop, but was rescued (our man-over board drills have been really handy) and got to flying again for one last hurrah! I must say it was sad after our last day, even though we were exhausted after it all and cleaning the whole boat- no more whales or towing arrays for a while 🙁
and now I am back to work!
All of last week seems to be blurred together because so much has been going on. We had a lot of time with the whales, especially when we headed all the way up the Georgia Straight to catch them. I tried to take a plankton tow up there but lost the bottle off the back of the net and ended up using a rubber scraper to get what microscopic life I could from the sides of it. The plankton ID stuff has been a little side project of mine and I was hoping to map the types of plankton along different areas in the San Juans with Robin, a post-doc fellow here at the labs, but I only ended up doing 2 samples all week! Leslie came on with Val yesterday and that was a lot of fun. We had mexican sushi for lunch and homemade pesto pasta(made by Dominique and Laura) for dinner. We cleaned the Gato Verde bottom to top today and even with all that team work it still took around 6 hours. It is a relief to be back in home sweet home S1.