Thursday, January 12, 2017

Beavers in Kansas

Photo credit:  Lyn Fenwick
Look closely.  Slightly above center and to the left you will see a beaver dam.  That lovely setting was photographed in Kansas and gave me the subject for this week's blog.  

Isaac B. Werner never mentioned beavers in his journal, and it is likely that there were no beavers on the Rattle Snake Creek near Isaac's claims.  Beavers are vegetarians, and while they feed on aquatic vegetation, such as cattails, waterlilies, sedges and rushes, they also like twigs, stems, and bark from trees.  When the early settlers like Isaac arrived to stake their claims, prairie fires had kept trees from getting established, so beavers would have found no wood to nibble nor with which to build their lodges.

Photo credit:  Lyn Fenwick
Of course, as trees were planted and prairie fires were controlled by the settlers, trees could be found, and beavers began to build their dams in creeks and rivers.  While beavers will chew any tree, among their favorites are cottonwood and maple, both varieties that Isaac and his neighbors planted.

Beavers build two types of lodges--a conical lodge surrounded by water to protect them from predators and a bank lodge excavated in the bank of a stream, river, or lake where the water is either too deep or too fast moving for them to build the more common conical lodge.
Photo credit:  Lyn Fenwick

Their lodges are made from sticks, mud, and rocks, with at least two water-filled tunnels to access the interior chamber where they sleep, eat, groom each other, and raise the baby kits born each spring.  The peak of the lodge is not covered with mud in order to provide a ventilation shaft.

The beavers build dams where the water is not deep enough to protect them from predators, and by backing up the water they create the depth to fill their entrance tunnels with water so predators cannot enter the interior chamber.  In slow moving water they build straight dams, like the one I photographed, but in fast-moving water the dams are more likely to be curved. 

Beaver teeth are well adapted to their life-long chewing.  The teeth never stop growing so they cannot be worn away, and the orange enamel on the front side is harder than the softer dentin on the back side of the tooth, which allows the back side to wear away as they chew, creating a chisel-like edge.  The flat tail, which makes them so unique and so recognizable, serves as a rudder when they swim, a prop then they sit or stand upright, and a storehouse of fat during the winter.

Photo credit:  Larry  D. Fenwick
Less obvious are other amazing adaptations, like webbed hind feet for swimming but hand-like front paws to assist in building and harvesting.  Hearing and smell are excellent, and although their eyesight is poor, a transparent membrane covers their eyes to protect them while swimming.  Flaps close over their nostrils and ears to protect them while swimming, and they have inner lips that keep water out of their mouths while swimming with sticks in their mouths.  Even their fur is adapted for their aquatic life, consisting of short fine hairs for warmth and longer hairs for waterproofing, with castor glands on the underside of their belly used in the grooming of their fur and to mark their territory.

While it is true that they are North America's largest rodent (typically weighing 45 to 60 pounds) and their dams do sometimes cause flooding, they are a remarkable animal.  Native Americans respected them so highly that they called them "Little People." 

It was my husband whose sharp eyes first spotted this beaver dam and snapped a photograph that he sent to me without any information.  I wrongly assumed it was a photo he had taken off the web from an out-of-state location.  Later, he took me to the location of the dam so I could see it for myself and take more photographs.  I love the beauty of this Kansas setting!   

1 comment:

The Blog Fodder said...

Lovely and peaceful. Great pictures.