Wednesday, January 11, 2012

Winter Field Trips

Students from Canyon Creek Elementary School recently spent a day at the Audubon Center learning about winter twig identification, animal adaptations to winter, and basic bird identification. Canyon Creek's 4th grade is part of our year-long Audubon Naturalists in the Schools program, which introduces students to phenology (the study of seasonal changes in nature) and how to explore the outdoors with the tools of a naturalist. During yesterday's visit, they learned how to use binoculars, bird field guides, and dichotomous keys.

In the photo on the right Mattie Clark, a Teacher Naturalist and Big Sky Watershed Corpsmember, is showing students how to tell whether a plant's branches grow opposite or alternate from each other. Students then use a dichotomous key to determine the twig's identification. The first step on the key asks students to determine whether the plant is coniferous or deciduous. In identifying winter plants, the coniferous ("cone-bearing") plants stand out because they are still green with their leaves (which are needles or scale-like leaves). Deciduous plants lose their leaves in the winter and appear naked in comparison.

After the students decide which major group the plant is from, they continue answering questions with two choices, working their way down the dichotomous key until they arrive at the correct answer. Here, the students are looking at a branch from Red Osier Dogwood. Later, during a birding hike, they identify the dogwood because of its bright red branches, which stand out against an otherwise brown background of dried grasses and woody twigs. They also learn to identify the Ponderosa Pine, whose needles grow in packets of three, and the Rocky Mtn Juniper, with its scale-like leaves and blue-green berries. As a demonstration site for vegetation that is found across central and eastern Montana, the Audubon Center hosts a variety of tree and shrub species that are native to Montana.

After practicing how to focus binoculars in the classroom, students went in search of winter resident birds. Together we spotted 13 different species of birds, including an immature bald eagle, male and female downy woodpeckers, northern flickers, and black-capped chickadees. Upon glassing the waters of the Yellowstone for a few minutes, we noticed some black and white dots that kept appearing and disappearing into the cold river water. These turned out to be a flock of common goldeneyes, diving into the water in search of invertebrates for lunch. These ducks are named for their bright golden yellow eye, visible in the photo of the male duck below (female duck eyes are a paler yellow). Interestingly, their eyes are gray-brown when they hatch. They change color over the first few months of their life, from purplish to bluish to blue-green, and finally to green-yellow by five months of age! They are winter residents in Montana, and will migrate further north into Canada come springtime. For more fascinating facts about the goldeneye, or to hear the unique sound of their wings whistling in flight, visit the Cornell Lab of Ornithology's bird guide website.

Posted by Heather Ristow, Education Director

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