Visitors might have seen St. Albert’s Miles Constable doing something strange at the Big Lake Environment Support Society observation platform in recent weeks.
He has been hauling up a bucket of water from the lake, sucking the water into a syringe, and squirting it off the platform.
Believe it or not, he’s been birdwatching. With science.
Constable, the treasurer for BLESS, is one of a group of volunteers across Canada taking part in a University of Guelph study that aims to detect birds through water-borne DNA. It’s been his job since Sept. 14 to head to the platform on Mondays to collect that DNA, which involves squirting lake water through a filter hooked to a syringe.
Birdwatching with DNA
This study was the work of Bettina Thalinger, a post-doctoral fellow and biologist at the U of Guelph, and was part of the federally funded Food from Thought project.
“Every organism that comes into contact with water releases and sheds a few cells,” she explained – typically through their feces in the case of birds. Those cells stay in the water for days, and can last months if they reach the soil.
Back in 2007, researchers realized you could figure out what lived in a lake or river by analyzing the DNA in the water, Thalinger said. Researchers have since used this technique to survey fish and amphibians, and she wanted to see if it could work for birds.
Thalinger said she reached out to stewardship groups such as BLESS through Bird Studies Canada to find volunteers to take water samples at 27 Important Bird Areas across the nation, including Big Lake, Lesser Slave Lake and the Travers Reservoir in Alberta. She picked these areas because they have plenty of birds, bird records and bird-watchers.
Constable said his role in the study is to run about 2 L (about 35 syringes) of lake water through a disc-shaped filter to collect DNA-laden material. The puck-sized filter mounts on the end of the syringe, and features holes that are just 0.8 microns wide – less than a hundredth of the width of a human hair. The filter usually gets so clogged by the 10th syringe or so that he needs to brace the syringe against the platform’s floorboards to apply enough force to the plunger.
Constable then adds a chemical preservative and drops the filter in the freezer until he is ready to ship his samples to Thalinger.
Thalinger said she sent about 400 filters to her volunteers to use from August to December. Once the filters reach her lab, she will add a molecular probe (a specific DNA sequence) to them that would seek out and replicate avian DNA, amplifying it. She will then use a computer analyzer to sequence that amplified DNA and compare it to the DNA of known bird species. If she finds matches, and those species match what observers actually spotted at the lake, she will have evidence that this technique works as a way to spot birds.
Constable said this research could help people find rare species or spot shifts in bird populations due to climate change. Still, given the vast array of species in Big Lake, he said it would be tough to sort the bird DNA in his samples from everything else.
“It would be a whole lot easier to go out and take a look at the ducks on the lake,” he said.
While it wouldn’t replace birdwatching, Thalinger said this technique, if it works, could help researchers track birds in remote areas and enhance our knowledge of bird diversity, which could help justify conservation measures.
Constable said he plans to keep sampling at the lake until early November or it gets too cold for him to do so.
Thalinger said she would send initial results of this study to her volunteers next spring, and hoped to write them up in a paper later.