Suppose you tried to bottle autumn and re-create it in a place where the season doesn’t exist naturally. How would you go about it?
Even with the Biodôme de Montréal’s sophisticated equipment, we need help. First, you have to ask yourself what it is that creates autumn. A keen observer would be able to name and precisely describe the changes that take place from one season to the next and that notably affect the famous trio: photoperiod, temperature and precipitation. You can’t have one without the other.
The manifestations of autumn are linked to the position and tilt of the Earth on its orbit. The result: in October the days get shorter, the nights get cooler, and precipitation is more important than in any other month of the year.
Imitating autumn at the Biodôme
To re-create those conditions, the Biodôme follows the Earth’s motion and deals with what the outdoor climate serves up. That means that at the heart of the Laurentian Maple Forest and Gulf of St. Lawrence ecosystems we use the external fresh air to cool these environments. The indoors thus follows the variations in outdoor temperatures. But there’s a limit, because we wouldn’t be able to operate all the hydraulic systems at temperatures below zero. So we have a system that heats the air to just above freezing before injecting it once again into these ecosystems. It gets cold, but it never freezes!
The magical autumn temperature is 10°C. That and the shrinking daylight period are the two factors that initiate leaf senescence, which is when we see a succession of red and yellow colors before the leaves drop to the ground. With strip lights, we manage to maintain an acceptable level of lighting for visitors without shifting the animals’ seasonal cycles too much.
Significant precipitation is taken care of by the horticulture team with manual watering. The water, as it flows over the leaves, branches and trunks, frees the plants of insects and other small organisms while ensuring hydration of the soil, which is very important at this time of year.
The Biodôme animals, meanwhile, remain active, although often in a slowed-down way. Only the turtles will be removed so that they can experience true hibernation. For an interval of at least two months, technicians place them in a stable and cold environment – meaning a fridge! Gradually prepared, they’re immersed in 4°C water in the dark for their winter cycle. The birds, well fed, will have no need to undertake a migration, and acclimatize naturally to the changes taking place in their environment.
In actual fact, there’s no winter at the Biodôme. The late-arriving autumn lasts longer than outdoors, while spring, for its part, appears a little earlier. That situation is ideal for all: the plants have what they need to carry out their cycle and can renew their leaves, while the animals experience a fairly pleasant cold season.
Re-creating autumn isn’t so simple, but pushing back winter, that we can do!
To learn more about the seasons at the Biodôme:
Le printemps arrive le 1er mars au Biodôme (in french)