Light up your life!

Tuesday September 22nd was the fall equinox, the transition when days begin to be shorter than the nights in the northern hemisphere. Did you know that the amount of hours of sunlight in a day is called a photoperiod?

Yellow-breasted Chat, an endangered migratory bird

We humans definitely notice the change in day length but local wildlife notice it too! Changes in day length cause changes in many animal behaviours as it signals a change of season. It alerts birds to start migrating and tells male birds to sing shorter songs less often. It also triggers snowshoe hares and some weasels to change the colour of their fur between white or brown for increased camouflage in snow or bare ground.

Plants also notice changes in photoperiod! A certain length of day will trigger flower production in some plants, as they need to be sure to flower at the right time so they will have the highest success of being pollinated and producing seeds. Plants need to flower at the right time so they will have the highest success of being pollinated by the right insects and producing viable seeds while avoiding competition.

Asters like this Showy Fleabane are short-day plants

With regards to photoperiodism, plants fall into three categories: Long-day, Short-day, and Day-neutral plants. Long-day plants are triggered to flower when thee days become longer in spring and early summer. Short-day plants flower when the days become shorter in late summer and fall. Day-neutral plants do not notice day length. Instead, they flower when triggered by factors like heat or growth stage

Plants and animals don't look at calendars when planning for the seasonal changes that occur, so they are always aware of photoperiods. All creatures and plants in an ecosystem depend on one another, and photoperiod is a dependable way to keep track of what is going on throughout the year in their habitats.

Interested in learning more about local flora and fauna? Head over to our Resource Library!