Silver Lining

As I’ve alluded to before, we had quite a few problems getting off the ground (as is always the case when mounting a large scale field project). One of the things that I’ve learned since I started working in field biology is that these setbacks, while frustrating and often expensive, can also be unexpected boons for any project.

Take for example our theodolite. To collect behavioral data on whales from the shore we use a high-powered scope traditionally used by surveyors. This scope gives us our geographic bearing to the whale (horizontal angle), and the angle at which we are looking down at our whale from the observation tower (vertical angle).

Theodolite Cartoon

We connect this theodolite to a computer running Pythagoras, a cetacean tracking program design explicitly for shore based theodolite work. It automatically converts these angles to Cartesian coordinates using trigonometry, the curvature of the earth, and adjusts for tide height. While I’m capable of doing this calculations manually the ability of the theodolite to communicate directly with the computer greatly increases our accuracy in terms of timing, as the computer operator can click a button and instantly store the data from the theodolite.

Without going too far into the details, we had some concerns about the calibration of the instrument we had borrowed, and it was giving us some trouble prior to leaving for the field. In the spirit of prudence we decided not to risk the field season with an instrument that might have (but in retrospect did not) prove to be faulty. I conservatively opted to replace the instrument, and located a replacement theodolite at a good price; only I later discovered that the company was a front, and the deal was a sham. At this point, running out of time, I took the advice of a contractor and began investigating total stations, which are like theodolites, only they contain many more features (none of which we need). I bought one in the nick of time and hauled her up to Alaska.

At the risk of running on too long about the technical details of this last minute equipment swap I’ll jump to the end of the story. The total station didn’t communicate with the computer, the theodolite had to be sent up to Alaska (via what was a pretty comical string of communication and the hard work of my buddy Kevin who happened to be dog sitting for me at the time, and who is unbelievably reliable). The theodolite was calibrated in field, looks to be totally fine, and what we ended up with is one total station – great for surveying, doesn’t talk to computers – and a theodolite that does talk to computers. Double trouble.

The total station is finicky, sensitive, and bulky, she doesn’t like surveying from the tower (which isn’t quite stable enough for her), but she’s super precise, and does the trick if she’s on solid ground. It seemed like a waste not to use the instrument since we had her, so we put the total station down on the beach to see just what would happen if we tried to survey from there. What failed in the tower, seemed to work just fine from the ground. So we decided to keep her, and run her. We call her the TB …. Because she’s a Total Beach.

What we’re doing now is running both instruments simultaneously (something I’ve been dreaming about- remember this conversation Garcia Lab?). From the beach we conduct scan point surveys where we mark every whale in the survey area and record it’s location, group size, and group composition. While we are unable to connect the total station to the computer, we are able to manually input the data into an iPad app called TapForms. The iPad, which is wearing a Lifeproof case, can withstand the rain and weather on the beach, making it ideal for surveying in the elements. We survey in 20 minute intervals and conduct anywhere from 15-21 scan point surveys per day

Meanwhile, in the tower we have our theodolite, which we refer to as the Darling because she’s such a delight to work with (even if her battery does turn off from time to time). We use the Darling to conduct focal follows. We pick a single whale, or a group of whale travelling together, and record their fine scale behavior (blows, surfaces, dives, breaches, etc.) as they forage and move throughout our survey area.

The result is a comprehensive picture of how the distribution of whales changes in the survey area as a single whale moves within it. In my imagination (I haven’t gotten this totally plotted yet) it will look something like this.

Visual cartoon

Pretty cool stuff right? But we’re just getting started. Once we have this visual picture we overlay our acoustic data to see if we can pinpoint which whale was vocalizing (fingers crossed it was either our focal animal, or an animal that our focal animal interacted with). By having both the broad distribution of animals and the fine scale focal follow data I can begin to investigate relationships between vocal behavior and social context, vocal behavior and foraging contexts (do lunging whales vocalize?), and ultimately I can glean something about what makes humpback whale produce these social sounds.

And it gets better…

Our area is subjected to very little vessel traffic, but we do have cruise ships that pass by predictably twice a day. By building our sampling schedule around these cruise ship arrivals and departures I can effectively ‘control’ for quiet periods and noisy ones. This gives me the opportunity to assess whether noise changes the acoustic behavior of the whales. Which is the ultimate goal of the Acoustic Spyglass project.

As one last added bonus, remember when I told you in my last post how close we’ve been able to get to the whales? This enables us to take fluke photographs as well as dorsal photographs that can be used to identify individuals that frequent our survey area. In many cases we hope to identify our focal animal. The whales in Glacier Bay are subjected to longterm monitoring by Park biologists (like my mentor and P.I. Chris Gabriele); many of these animals are of known sex and age class. While in year one our sample size many not be large enough to glean differences in behavior as a function of age or sex, after a second year of data collection we may have enough representative samples to begin investigating questions of this nature.

So while the first few weeks of our field season were… rocky. I’m happy to report that this rocky start has effectively doubled the amount of data that we’re able to collect on any given day, while simultaneously allowing me to collect behavioral data on multiple spatial scales.

While I hope this has been informative for those of you reading through this blog, I realize that the only pictures I’ve posted so far are cartoons. So, to scratch the photo itch I bring you a small slide show of beautiful moments from our field season to date. As lovely as these photos are, I assure you they don’t come anywhere near to the reality of just how spectacular this place and these animals really are.

Your Alaskan Correspondent,


*Note- we have not yet had any negative encounters with our neighborhood bear, though she has been visiting a little more frequently. Meanwhile our Oyster Catchers are raising a family (we have two new additions on the island) and our vole community (not pictured) is thriving.

This slideshow requires JavaScript.


One thought on “Silver Lining

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s