“It’s not unusual for February, March, for the weather to go up and down,” said Andrea Sudak, horticulture technician at the Humber Arboretum, but challenges are posed by such rapid shifts in temperature, like sparse leaves on trees that begin to bud too early in the season.
However, a lot of bigger animals can benefit from an early thaw, Sudak said. “They actually have a better food source because they’re able to get to the grass, they’re able to get to some of the buds on the trees … so you’ll see a lower mortality rate, especially in deer.”
Ken MacGillivray, an education assistant at the centre for urban ecology located in the arboretum, gave another example of multiple species affected by the warmth.
“The risk to the tree(s) from the milder weather like this is more to do with the insects waking up early. A lot of our sap buckets have been attacked by ants already and if we had the proper cold at night, the ants wouldn’t be waking up like this,” said MacGillivray.
He also mentioned invasive species like the emerald ash borer, which has killed most of the ash trees in the arboretum over the years. Sudak said that warmer bouts of weather give an additional life cycle to a lot of these invasive species, which can make it difficult to prevent the damage they cause.
Toronto and Region Conservation project manager Sue Hayes noted the importance of understanding what climate change really means.
“I think that’s one of the key things that people have to recognize … that the day-to-day temperature isn’t about climate,” Hayes said.
Changes that occur over a much longer period than what can be observed in a single season are more indicative of a changing climate than simple changes in weather, she said.
“It’s also an El Niño year so that means that we would be getting this kind of weather probably anyways … of course everything’s going to be a little bit exaggerated when you’re adding that much energy to the Earth every year,” said MacGillivray.
El Niño refers to the shift in atmospheric circulation that happens when the surface waters in the eastern tropical Pacific heat up according to Environment Canada.
For anybody still confused about whether or not they should worry about weather, Sudak said “it’s very unpredictable.”