HOLDEN – As October folds into November, animals at Fields Pond Audubon Center are getting ready for cold weather ahead.

The bluebirds that raised their young at the center are long gone, heading south. But other bluebirds were seen this week.

They were young ones, with spots still on their breasts, like young robins. Probably these bluebirds came from northern Maine or Canada and are on their way south. They will spend the winter in Massachusetts, New Jersey, Virginia, the Carolinas or thereabouts.

A hermit thrush was spotted in the shady forest on the scenic Ravine Trail. It’s not an everyday sighting, because thrushes love the dense forest. In such a habitat, these dark-brown birds blend in and are hard to see. They are not singing now. All their energy is used for the arduous migration south. Next May, their beautiful song will echo down the ravine and bring joy to all the birders below.

A garter snake was spotted on the forested Ravine Trail, too. In summer, visitors see garter snakes on the mowed trails in the fields, presumably looking for grasshoppers, slugs and other prey in the grass. In the fall, they are seen in the forest, presumably to find a good place to hibernate.

A green frog was seen basking in the center’s tiny pond next to the building. That is a created pond, with a plastic substrate – no good to hibernate in. The water under the ice doesn’t have enough oxygen to sustain frogs all winter. In late October, volunteers net the frogs in the little pond and re-locate them to the big marsh with a stream flowing through it, which has lots of deep muck for them to burrow into.

Chipmunks are stuffing their cheeks with birdseed dropped from the center’s bird feeders. They have a well-provisioned, underground larder which helps them get through winter and the hard days of early spring.

Children and adults often don’t differentiate between chipmunks and red squirrels. This week, children on a Secrets of the Forest walk saw both species close together. The youngsters had a good look and a good lesson on the many differences between the two animals.

Examples of differences between chipmunks and red squirrels are: bright beige vs. dark reddish brown; stripes on the back, no stripes on the back; live mostly underground, live mostly in trees.

For information on Fields Pond Audubon Center, call 989-2591.