Wednesday, July 21, 2010

Whales in the Fog

When I got to Lime Kiln this morning, I didn’t have a good feeling about the day. I had missed the whales by ten minutes, and apparently it had been a very exciting passby. A few minutes later I saw a huge splash on the horizon – the second half of J pod was coming north behind the group I had missed. They passed us slowly and didn’t come very close to shore, but the hydrophones picked up some interesting sounds. Recently, J pod has taken to using a flat-frequency pulsed call that I can’t identify. It sounds something like S16, a common K pod call, and Jeanne Hyde and I are starting to wonder if J pod whales are imitating their K pod relatives. Listen to the clip below and leave a comment if the call sounds familiar to you. I also heard another strange call that I have now heard on three or four occasions. I've dubbed it the “human call” because the first time I heard it, I thought a person was making the sound! Listen to the second clip and let me know if you’ve ever heard this call (turn the volume up all the way to hear).


Around 9:30, we got word that the two J pod groups had met up to the north of us and were heading back down toward Lime Kiln. At this point, a thick blanket of fog had rolled in and we were relying on our ears to detect the whales. By the time they got to us, the whales had fallen into a resting pattern and were tightly bunched together. This is one of my favorite ways to see killer whales, and the experience was made all the more ethereal by the fog surrounding them. Some animals were still active and we could make out their profiles as they breached just beyond our view. It was strange to hear the huge splashes without being able to see what the whales were doing! At this point, the whales were vocalizing very little, as is common during resting. The group (which consisted of J pod and a few members of L pod) turned around one more time and drifted north with the flood tide.

Monday, July 19, 2010

Detecting whales at night with Infrared

I thought I'd share a little about a cool project we helped with at Lime Kiln a couple of weeks ago (July 6-9).  Jim Thomson, Joe Graber, and Brian from the Applied Physics Lab at the University of Washington, came up to Lime Kiln to test out the feasibility of using infrared and thermal cameras to detect whales at night.  During the week they installed 3 cameras; an infrared camera, a web camera, and a black and white camera.

Why, you ask, is it important to detect whales at night with infrared cameras when we have hydrophones that do that?  Well, the reality is that the resident orcas make some awesome sounds, but they don't always make sounds, so it would be nice to be able to detect them even when they aren't calling.  This is most important in regards to marine renewable energy projects.  If new projects are approved there will be a need to monitor marine mammals in their vicinity during the day and night. 

During the week that they were here, the whales obliged by going past the light house several times during the night which allowed for some pretty nice videos and some great data that Joe will be working on for his masters degree.  Watch the video below to see one pass by on the night of July 7th.  There are two animals that surface first, and if you look closely you'll see a calf come up just to the left of the animals.

Sunday, July 18, 2010

Maintenance Dive on July 16, 2010

David Howitt. and I did a dive at Lime Kiln to achieve three things.  Install a new hydrophone, grounding cable and an underwater video camera.  We did the dive near high tide and managed to to get everything done, which is not always guaranteed on a dive because you're never sure what you will find down there.  We had good support from shore from David King, Kathryn Scurci and Dino.  This was important because we had a bunch of cables and a rope that we had to pull through our protective pipe that runs through the intertidal.  We needed to install a new hydrophone because one of our hydrophones had failed.  We have five hydrophones just off the light house that we are using to record ships and whale calls to try and determine if ship noise is impacting the whale's ability to communicate acoustically.  This replacement hydrophone is one of the ones that we use for calculating the position of the calling whale.  Below is a picture of how we mounted the hydrophone on the stand underwater.  All the underwater pics were taken by David Howitt.

Don't be alarmed by the knife!  I'm not trying to cut any cables, just the ends off a zip tie so that it doesn't bang against a hydrophone.  The hydrophone stand is an old tire filled with concrete, with a PVC pipe sticking out of it so that we can fasten instruments to it.  The long object on the top is our Reson hydrophone, which is our broad band hydrophone that allows us to record sounds over a very broad range of frequencies (pitch).  Although it's hard to see there are another two hydrophones fastened to the PVC pipe below the Reson.  Yes, it's true, we do a lot of our fastening down there with electrical tape.  It is amazing how it sticks to itself, even under water.  That blue thing on the left is the camera we installed on this dive.  It is was a little tricky deciding how to 'frame' the shot from that camera, especially since we couldn't see the shot (you have to view it from the computer on land).  We decided to try and aim it up and back towards land since that way at least we could see the kelp.  We hope that we might be able to record a few orcas swimming past this summer, but we'll see if we get that lucky.  Below is a short clip I took afterward to make sure the camera was working.  Since the currents were picking up you can see how much kelp fronds oscillate in the current.


The grounding wire was installed to try and decrease the amount of hum that you sometimes get from trying to record sound.  This is usually the 60 Hz hum that you get from the power lines, but we also sometimes pick up stuff that isn't really audible underwater, like radio transmissions.  It's amazing how much of a difference having a grounding wire can make.  We attached our grounding wire to a metal pipe to make sure there is plenty of metal exposed to the water to make a good ground.  This is what the setup looked like.


The dive itself went really smoothly and we actually got to see a lot of stuff around us.  Sometimes that is not the case since we are so busy.  This time around, there were a couple of rock fish that didn't seem concerned about us at all.  In fact they almost seemed inquisitive since they watched us feeding cables and rope through the protective pipe from a distance of only thee feet.  Here is a pic of one of them.