Behold the Common Loon. The Great Northern Diver. Scientific name Gavia immer. The bird that lent its image and name to the one dollar coin, the “loonie”.
Well, there’s a new loon in town, and this one is not very common. UBC-Gavia, the autonomous underwater vehicle (AUV) named after the Common Loon, is the robot that will be diving beneath the surface of Pavilion Lake this summer. As one of only a handful of Gavia-class AUVs in the world, and one of only two in Canada, seeing this uncommon loon is a rare and special sight in Canadian lakes.
This year we are particularly excited to have Dr. Art Trembanis joining the project who will be bringing some very high-tech toys with him from the University of Delaware. Dr. Trembanis may have an uncommon name (apparently he is one of only 6 Trembanis’ in the world – the other 5 being his immediate family) but he’s certainly no loon. Art is the happy owner of another Gavia AUV that is equipped with an inertial navigation system (INS), the navigation instrument found on commercial airliners. This allows his Gavia to fly with unprecedented location accuracy and precision underwater. Due to the interchangeable modules on the Gavia AUVs, this also means he can bring the INS module with him to attach to UBC-Gavia for the Pavilion Lake project to collect high-resolution spatially referenced data. It is also an excellent idea when there are multiple submersibles flying around the lake at the same time (UBC-Gavia and the Deepworkers) to know precisely where each one is. Avoiding an unplanned underwater encounter is priority one!
One of the goals of Gavia at Pavilion is to help us track the flow of groundwater inputs into the lake. There are several springs that flow into the lake underwater and depending on the chemistry of this groundwater these springs may play a role in microbialite formation. We expect the groundwater may be more saline and dense than the lake water and so will creep along the bottom from its sources to the deepest part of the lake. Flying UBC-Gavia in precise bottom tracking mode, equipped with the INS, will help us focus in on the path of the groundwater and allow us to send the Deepworkers in for a closer inspection.
Another exciting first for this field season is that we hope to test a water sampler prototype designed by three undergraduate engineering students at UBC. Gabriel Hamilton, Jadon Harrison and Mark Mosher, designed and built an independent bottle system that attaches to the the outside of UBC-Gavia. This will allow us to collect small water samples at depth during the mission and return them to the surface for analysis. The team has successfully tested the sampling system independently, now we want to put it through its paces in the field on UBC-Gavia. A robust and functional water sampler attached to the AUV would permit the collection of samples from locations that may otherwise be inaccessible and expand UBC-Gavia’s capabilities for biological analysis (as a molecular oceanographer this is very exciting to me!). The team of undergrads will be giving us a demonstration of their water sampler this evening, so we’re looking forward to seeing it in action.
So if you happen to be at Pavilion Lake during the first two weeks of July, watch for the rare uncommon loon diving under the water. It will be followed closely at the surface by a more common loonie (yours truly) in a zodiac (although I think it’ll be a while before my image makes it onto a coin!).