by Lars Wilsson
translated by Joan Bulman
At the time this book was written, little was known about beavers. I never read about these animals before, so even though the book is rather outdated it was still very interesting to me. My Beaver Colony is based on the work of two men in northern Sweden, who sought to rescue and study a population of beavers on the river near their farm. When the government began regulating water levels in the river via a hydroelectric dam, it disrupted the lives of beavers downstream so much that they were threatened with starvation. Rather than watch all the beavers die, Wilsson and his friend began trapping them, and ended up keeping many in captivity until they found suitable locations to set them free again, where they could study their behavior in a natural habitat. From observing the beavers' behavior in terrariums, Wilsson learned for the first time how much of their building work is instinctual. The young beavers who were caught before they had opportunity to observe adult beavers building went through the proper construction actions (even when they had no materials, or those at hand were unsuitable). When the beavers were set free outdoors, they successfully built their lodges and dams on the first try. It was amazing to read how the animals go about their building work, and how well their lodges are engineered- I never knew before how extensive their tunnels under a river bank can be, or that they build the lodge first, before making a dam. Wilsson conducted many experiments to find out exactly what conditions in the river or stream stimulated the beavers to build dams. It was interesting to read his speculations on how natural selection might have shaped the beavers' building behavior. Some things which at first I thought showed the animals' intelligence turned out to have other possible explanations. For example, when he first described how the back side of the lodge closest to the bank was left unplastered with mud, allowing airflow to ventilate the lodge and underground tunnels, I thought: wow, those animals are smart! But it turns out that carrying loads of mud across the shore to plaster the back of the lodge would expose the beavers to predators, so they probably avoid fnishing that side of the lodge just because it is too risky.
This is the first book I've finished reading for the 9 for 09 Challenge. It fit under the category of "book with the ugliest cover". Well, it's not terrible, but I thought it really tacky and there were some better photographs inside the book (although not in color).
Rating: 3/5 ........ 154 pages, 1964
Has anyone else read this book? I'll post a link to your blog review here.