Last month I traveled to Swansea, Wales, Great Britain (by plane) with two freeze-dried Western Grebes. After a 4-hour train ride to Swansea, a short cab ride (automobile), and horrible jet lag, I was finally there (except for the fact that I had to drag my suitcase and the box of birds up three flights of narrow, crooked stairs, as they had no elevator in the “guest house”). Telling people that I “traveled to Wales with two freeze dried Western Grebes” is a great conversation starter, as not too many people get to travel across the Atlantic with two wild birds, let alone birds that have been frozen and then dried (why in the world would you ever do that??). When I tell people this, and once they finish their evaluation of whether I have finally fallen off my rocker, I can further explain why in fact I subjected myself to ten hours in a cramped airplane seat next to a very large (and smelly) Rugby player, inevitable jet lag, and bad British food for this.
Freeze dried Western Grebe on the box that brought it to Wales.
The reason for this trip was to work with our collaborators, Sylvie Vandenabeele and Rory Wilson at Swansea University. Our collaboration involves a study to track grebes after oil spills with the use of externally attached satellite transmitters. I will get back to this in a minute, but wanted to diverge, so as to fill you in on some of the background information to complete the picture.
Western Grebes are a species of concern on the west coast of North America, as populations have declined pretty dramatically over the past several decades, particularly in Washington state. This decline is disturbing in and of itself, but especially because there is no smoking gun (or more likely, guns) for this decline. On top of this piece of bad news, Western Grebes are often impacted by both large and small (including natural seep) spills. One of the missing pieces of this puzzle is a reliable method for being able to follow grebes that have been rehabilitated after oil spills, to see where they go, how long they survive, and if they return to “normal” behavior, such as breeding. The tricky part has been that grebes have shown little tolerance to external tracking devices. Because of this, there have been several studies with implantable satellite transmitters on grebes, including one in 2010 that was a collaborative effort between several folks from UC Davis, USGS, and field help from the Washington Dept. of Fish and Game. The results from this study are currently in the process of being reviewed for publication. The bottom line is that to use implantable satellite transmitters requires subjecting grebes to surgery, and this method, although very promising, especially with recent surgery modifications, is not 100% successful. Therefore, without completely disregarding this option of using implantable transmitters, we are also exploring other options, including returning, once again, to external devices on the birds. The tricky part to this is that, as mentioned before, grebes are especially sensitive to stuff on their backs, and also, placing anything externally on a bird is going to somewhat alter how the air and the water flow over them when they are flying and diving. This is, in a nutshell, why I traveled across the Atlantic with these two birds.
Several satellite transmitters, including two from Sirtrack (black ones), a 9.5 solar one from North Star, and the implantable one that was used in the 2010 study (yellow).
As we all know, technology advances at a very fast rate, and when it comes to satellite tags (and other tracking devices), they are no exception. These cool devices (if you are a gadget geek like me) have become smaller, lighter, and generally better, including some with cute little solar panels instead of batteries (see picture). So we felt that the time was ripe to re-visit the external attachment option. Western Grebes are not only strikingly beautiful birds, but they are also equally fascinating, as they breed in inland lakes but spend the post-breeding winter months along the Pacific coast in marine waters. So these birds, in order to do well with anything attached to their backs that tracks them, must be able to fly well (for their long migrations) and swim and dive well (as that is how they get their food).
Sylvie demonstrating how to attach a satellite transmitter to the back of a Western Grebe.
OK, now that you have a general idea of some background information, let’s get back to Swansea. The original idea with the birds was to test them in the wind tunnel at Swansea, which Sylvie and Rory have ample experience with, in order to figure out a few things, including the best location to attach a satellite transmitter on a grebe so that the amount of drag in the air (while flying) and in the water (while diving) is minimal. The other aspect of this study is to run these wind tunnel tests with several different types of satellite transmitters (that have different shapes, length and flexibility of the antenna). Once these steps have been completed, we will be testing a very lightweight and flexible harness system to attach the satellite transmitter to. The types of harnesses we will be using have been designed and developed by Sylvie (who presented some of her OWCN-funded research at the Effects of Oil on Wildlife Conference in New Orleans in 2012). Our hope is to test out the harness system (first by itself, and then with a device) on live grebes at rehabilitation centers in California. We will be observing the birds closely during this step, to look for signs of discomfort, chaffing, or injury caused by the harness, as well as making sure that the birds’ waterproofing is not affected.
Our hope is that by the completion of this study we will be armed with better knowledge on the best type of satellite transmitter to use that will minimally impact normal behaviors of the grebes, how best to attach it, and the ideal location to place it along the grebe body, so that we are ready to track this species after an oil spill.