Cause of mass bird deaths revealed
Some 56 Mallards and a Canada Goose died in a park in Calgary, Canada, due to starvation and exposure. Alberta Environment and Parks confirmed the reason behind the grim scenes, which were discovered during the last week of February in Elliston Park. A few carcasses were discovered initially by Heather and Wayne Clarke, with more and more dead birds being found in the following days. This sparked an investigation with the outcome ruling that limited foraging opportunities drove the mass deaths.
Alberta Environment and Parks and the Canadian Wildlife Health Co-operative at the University of Calgary investigated the incident at the stormwater pond, and in a statement said: "[We] have determined that the ducks suffered from starvation and exposure, which was the likely cause that led to the mortality of 56 Mallards and one Canada Goose. Some additional tests are underway to rule out other causes of death."
The grim scenes were discovered during the course of a week (Wayne Clarke).
Due to extremely cold temperatures, birds that spend the winter as far north as Calgary can face a particularly tough time – particularly wildfowl, which depend on open water. It's thought that particularly harsh conditions sparked the sudden death of such a large number of birds.
When Mr and Mrs Clarke first came across the load of dead animals there were only a handful of bodies, but open further visits to the pond during the same week many more appeared. Wayne Clarke said: "We couldn't believe it … after a week, 50 birds, scattered around – unbelievable. I've been hiking around this lake here for 17 years and I've never seen it like this."
Brett Boukall, Senior Wildlife Biologist at Alberta Environment and Parks, added: "When we see this overcrowding, the birds might not be able to feed effectively, they might not be able to protect themselves from the elements. It's possible that if one of them is carrying a disease, it can spread more quickly when they’re in a tighter group in a smaller area."