Pollution may be making male tree swallows shinier, suggests a new study done in part at Big Lake.
University of Alberta PhD candidate Natalia Lifshitz will give a free talk at the Edmonton Nature Club next week on her research into the effects of pollution on tree swallows.
Tree swallows are small, agile, insect-eating birds with white chests and dark-blue heads and wings. While they normally nest in trees, they readily camp out in nest boxes.
Lifshitz set up 24 tree swallow nest boxes at Big Lake in 2016 as part of a three-year research project. Similar boxes were raised in downtown Edmonton and Beaverhill Lake (near Tofield).
For the first part of her study, she caught about 80 tree swallows at the nest boxes and took feather and blood samples from them. She also weighed any chicks in the boxes and collected their poop. Last summer, she also used tiny cameras to photograph the birds as they entered the boxes.
“Some of them were very aggressive,” she said of the birds, and would dive bomb and scream at her as she approached the boxes.
“It’s quite fun to see those little guys being so aggressive at you.”
Lifshitz analyzed the blood and poop for heavy metals and studied the colour of the feathers using a reflectance spectrometer. Her initial results suggest that birds exposed to more copper and zinc had feathers that were shinier but less saturated (less blue) than those exposed to less.
That’s significant, as saturation and shininess affect reproduction in tree swallows, she explained. Previous studies have found that swallows have more chicks with their mates when they have bluer, more saturated feathers, but also have more extra-marital chicks when they have shinier feathers.
Tree swallows “cheat” on their partners to enhance their reproductive success, Lifshitz said. But if males exposed to more pollution look shinier, that could give them an artificial advantage over other males, making them appear to be better partners for affairs regardless of their genetic fitness. That could lead to lower tree swallow populations.
Lifshitz said she would discuss the implications of her research at her talk, as well as her future plans to determine pollution levels in swallows based on photographs of their feathers.
The talk is in Room L116 at 7:30 p.m. on Nov. 30 at The King’s University in Edmonton. Visit edmontonnatureclub.org for details.
Green award proposed
City council should come up with a new award to recognize St. Albert’s environmental champions, the city’s environmental advisory group says.
The St. Albert Environmental Advisory Committee called on city council Thursday to make environmental stewardship an award category under the city’s Community Recognition Program.
The program currently honours St. Albert residents for achievements in arts and culture, citizenship, professional achievement, and sports, as well as current and past businesses of distinction. Recipients are nominated by the community and have their names engraved on the stone monument near the corner of Perron St. and Sir Winston Churchill Ave. across from the clock tower.
This is the 10th anniversary of the city’s Environmental Initiatives Grants (which are awarded based on advice from the environmental advisory committee), and the group decided it was time to start recognizing St. Albert’s environmental leaders, said committee chair Tanya Doran.
The committee advised council to create an award that would recognize environmental stewardship related to the built or natural environment.
“It’s pretty broad at this point,” she said of the award’s qualifications, with achievements related to tree planting, wildlife, watershed protection, waste reduction or energy conservation all possibilities.
Doran said this would be St. Albert’s equivalent to the Alberta Emerald Award, which is this province’s premier environmental honour.
“I’d love to see the nominees!”
Doran said there would likely be just one recipient in this category per year to start. She hoped council would have the committee screen the nominees.
The committee’s recommendation goes before council this January.