As global warming quickens its pace, naturalists and scientists are being cautious about their predictions as to how the landscape of Muskoka could be altered. Many changes could be so gradual that most people will be unaware of what new species have entered the area and what is at risk of being lost.

Scientists and naturalists cannot predict an exact future but with warmer summers and shorter winters on the cards, the landscape of Muskoka could slowly alter, with many southern species getting a foothold

Ontario is stratified into areas defined by latitude and land formations. Algonquin Provincial Park is the southern range of the northern area or boreal area. Muskoka sits on the Precambrian Shield and to the south is the Carolinian Forest area. Naturalists are already seeing southern species moving into northern areas and extended seasons for migratory animals.

“Today we are seeing southern species that were not here 20 years ago,” says Algonquin Provincial Park chief naturalist Rick Stronks. “The first turkey vultures arrived in the park in 1991.”

The park elevation allows for land formations that are only found in the north. Spruce bogs are a good example. These are bogs where special grasses and mosses adapt to high acidity and low oxygen levels. A floating mat of vegetation grows out from the shore. The bogs are surrounded by spruce trees and tamaracks that are home to northern birds. If warmer weather dries these bogs out, species could be lost.

“The Gray Jay only exists in northern areas and is there all year round,” says Stronks. “This species has been negatively impacted over the last 35 years. There are about half as many in the highway corridor as could be seen 30 years ago.”

Gray Jays store food in summer behind the bark of the trees. “It’s like putting it in the fridge,” says Stronks. “Warming will spoil this food. At least, this is a theory.

“We are already seeing migrating birds returning a week earlier: robins, belted kingfishers and loons. Certain species of birds and insects are particularly good specimens for monitoring.”

Naturalists are watching for changes to migrating insects like butterflies and dragonflies. Many insects winter in a larva stage or as an adult but some, like Monarch butterflies, migrate.

Bob Bowles, a naturalist who runs an environmental consulting business out of Orillia, is a member of the North American Butterfly Association and has been monitoring butterflies and dragonflies in Muskoka since 1968.

In the last five years, Bowles has sighted a number of southern species moving into Muskoka: butterflies like the Fiery Skipper and the Giant Swallowtail and dragonflies such as Halloween Pennants, Blue Dashers and Familiar Bluets. Bowles also says gradual changes are hard to see. “Keeping records for years is a great way to track distribution patterns and general movement of species,” he says. “It is a record for the impact of warming trends.”

Species moving north need specific food sources and there are also plant species moving north. Bowles explains that all species live in a small niche in the natural habitat. It is possible that one species could disrupt the habit of another, but it would be very gradual.

“This is different with species imported from Europe and Asia,” says Bowles. “They have a devastating impact.” He cites spiny water fleas and zebra muscles that came to Canada with ships taking on ballast. There are varieties of insects that come in with imported fruits. There are the ramifications of purple loosestrife strangling wetlands with a monoculture. This was a pretty flower brought from Europe for gardeners.

“Global warming will have ramifications and there will be species that won’t survive, but man’s activity is having the largest impact on the environment,” adds Bowles. “Man is supposed to be the wisest creature, but you have to wonder if it is true with some of the things he is doing to the environment.”

Muskoka’s elms trees are still being hit with the second wave of Dutch elm disease, which is a virus spread by a beetle. The first wave went through in the 1960s. The disease arrived in Canada by ship, a hundred years ago from Holland and had to work its way from the coast, says Mike Walsh, stewardship co-ordinator with the Ministry of Natural Resources in Bracebridge.

“Muskoka is 80 per cent covered with trees and it is getting better all the time,” says Walsh. “The days of logging and clearing for farmland are over. Now people are reforesting their properties.”

Walsh’s expertise is in forest management. He says Muskoka has not lost any variety of trees and it is still too soon to forecast what might happen if temperatures do rise. “People are planting non-native species like black walnut and they are surviving,” he says. “These trees produce an acidity that is detrimental to other trees, but one tree here and there is not going to make a difference. A good frost or minus 40 winters would eliminate these trees.”

Al Sinclair is a naturalist who lives in the Bracebridge area and is a well-known birder. “Birds that catch insect in the air, ‘aerial insectivores’, are in steep decline,” he says. “In Muskoka purple martins are down to one colony of just a few pairs. All species of swallows, chimney swifts, whip-poor-wills and nighthawks are disappearing or declining in numbers throughout the district.”

Although the cause is not known for sure, it is thought that more extreme weather patterns, sudden cold snaps and extreme heat, are causing nesting failure because the birds cannot find enough food for their young during these extremes.

Typical southern bird species seen more often in Muskoka are red-bellied woodpeckers and Carolina wrens, says Sinclair. Cardinals and mourning dove numbers are at an all-time high.

“Wild turkeys are surviving the winter here, farther north than they were before Europeans arrived,” he says. “These wild turkeys may be having an impact on other ground-nesting birds. They are opportunists that will eat the eggs if they find them.”

Birds are not the only things being displaced. “Some of the more sensitive plants are declining in numbers, in particular the orchid species that grow in drier sites,” adds Sinclair. “I have noticed that the large round-leaved orchid and the stemless lady’s slipper are dying out at many locations. Summer drought and high temperatures might cause this.”

One of the problems of disappearing species is determining if observations are the results of global warming or those of a natural cycle.

“In 50 years there is no doubt that there will be big changes, but no one knows what they will be,” adds Sinclair. “We can only guess how the plants and animals will be able to adapt. Plants in particular can’t move their range fast enough. Some species like the sugar maple may become very rare or even extinct because they will die out here before they can establish farther north.”

Moose are a northern animal at their southern range in both Algonquin and Muskoka. There are currently less than 2,500 in Algonquin Park when there were 4,500 five or six years ago. “When white-tailed deer move into an area the moose do not do well,” says Stronks.

“The reasons for declining moose populations are complicated,” he says. “White-tailed deer are a factor but not the only factor. But as you get more and more deer, you get less moose.”

The white-tailed deer carry a parasite called brain worm, for which they have a tolerance and the moose do not. In 1970, all the white-tailed deer disappeared from the park. There is speculation that this was caused by a lack of food and hunting by wolves. By 1980 the moose population had come back to what was a sustainable level. In 1991, the white-tailed deer started to come back in the park and the moose populations started to decline.

“Future sightings of moose in the park are going to be rare, even though the park has extended its season with camping right into October,” adds Stronks.

There is work going on into bass research. The Harkness Laboratory of Fisheries Research in the park has up to 30 scientists and graduate students doing papers. Research scientist Mark Ridgeway works on fish research in the park and has an office at the MNR centre in Peterborough.

Ridgeway says the big story is bass. “There are lots of them and they are growing faster,” he says. “These are smallmouth bass and they like warm water. This year has been unusual because it is October and the temperature of the surface water, or upper strata, has not cooled to mix with the colder waters below. Normally this starts in September. The daytime high on September 25 was 32º C. The average temperature of lakes is two to three degrees Celsius warmer than it used to be.”

Ridgeway says he does not see coldwater fish like trout disappearing, not as long as there is an ice covering every winter.

Stronks says changes to vegetation are more gradual and will not be noticed. “Whether global warming means more or less precipitation, we don’t really know,” says Stronks.