Phenology - May 2013

By Kelly Amoth, Interpretive Naturalist

Two weeks ago as we turned the calendar to May, there were snowflakes falling outside, and today at the mid-point of the month, we may see our first 90 degree day in the Twin Cities. It's amazing to see the changes that come with a few bright, warm sunny days. We still have a few holes on our phenology calendar that I am expected we will fill this month.

• Our fireplace was well used this winter, but now our attention and ears turn to it in hopes of hearing chimney swifts inside. These birds are sometimes called "flying cigars" because they are rarely ever seen perching. Chimney swifts are almost always in flight catching and eating insects. Usually the only time they will perch is while they are on their nest or roosting at night. They use their long claws to cling to vertical surfaces such as the walls of chimneys where they build their nests out of twigs. The chimney swifts build a nest shaped like a half saucer out of twigs that are held together with their saliva. The nest is also glued to the wall of the chimney with saliva. Chimney swifts are extremely social birds and during the non-breeding season many will roost together in one chimney. During the breeding season, there is often only one nest per chimney, but sometimes the nesting pair will allow other chimney swifts to roost in the chimney as well.
• The first of the spring ephemerals are beginning to emerge from the leaf litter. One of the first flowers we see every year is bloodroot, which has white flowers with 8-12 petals and large leaves that appear to clasp around the flower. Its name comes from the blood red juice that comes out of its stem and roots when broken. The petals are shed shortly after the flower is pollinated by bees or flies. Seeds develop in a seed pod and are actually dispersed by ants, which are attracted by the outside covering of the seed called the elaisosome. Ants carry the seeds back to their colony and feed the elaiosome to the larvae. The seed is discarded in the ant colony, which is a safe place for it to germinate.

The temperatures are heating up and so are our public program offerings! Be sure to check our website and sign up for one today!

What is phenology?

Phenology is the study and science of appearances and how they change over the seasons. The word itself is related to the word phenomenon. Think of phenology as recording and studying the natural phenomenon that occur around us every day.

Phenology can be as easy as recording what day you see birds returning to your feeders each year or when you see flowers blooming but make no mistake, phenology is serious science. By studying phenology we can better understand how the earth changes. Phenology records going back hundreds of years for the same location have even supported global warming research by showing that spring is arriving earlier than it used to historically.

At Warner Nature Center, groups help us fill out our phenology calendar each year and naturalists enter the data into a computer database.