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Showing posts with label bear. Show all posts
Showing posts with label bear. Show all posts

Sunday, June 16, 2013

One Bite out of Three and Wildlife



So, we all agree that we owe one third of our food to pollinators. Now let us stop thinking about us; instead let us devote a few minutes to our companions on planet Earth. Does wildlife need pollinators as much as we do? It seems that nobody has looked at this matter systematically, thus, it is not an easy question to answer. Yet, we can try.

I will try to look at the diets of some feathered and furred creatures, mammals and birds and ignore for now the scaly or slimy sorts, amphibians, fish and reptiles. I will merely list the foods that need the services of pollinators, rather than attempting to estimate percentages for lack of information in the matter. What we are trying to see is whether wildlife requires the services of pollinators. Also, I will not bore you with long lists of animals and their diets, simply limit myself to some better known examples.


Birds that come to our backyard feeders are easy to observe. They show a preference for sunflower, thistle and peanuts. Summer and winter, many birds depend on berries, from blueberries to raspberries to crabapples to holly. Of course, not all their food is insect pollinated like the ones mentioned above. Many birds feed on insects and or grass seed. You can learn more about the role of pollinators on the diets of some of the most beloved songbirds such as wood thrushes and blue birds at the North American Pollinator Protection Campaign fact sheet.


Another common wildlife of our forests and backyards is the squirrel. The eating habits of squirrels are similar to ours as a look at the way they dig through our leftovers proves. When there is no human garbage around, they go through a variety of berries, seeds and tender leaves. It would be safe to conclude that they are as indebted to pollinators as we are. The same could be said of raccoons.

One animal that symbolizes wildlife more than most is the bear. Let as take a quick look at what a bear eats through the year. When it comes out of hibernation, there isn't much plant life around, except for skunk cabbage, and skunk cabbage becomes its breakfast, lunch and dinner with some Jack-in-the-pulpit as a side dish. A bear must have a strong stomach because these plants have tiny salt crystals that would make most other animals, including us, very, very sick. I mentioned in previous posts that skunk cabbage and Jack-in-the-pulpit are both pollinated by small flies, which are the only pollinators flying around so early in the season.


Other foods become available later on. A bear will add some vegetables to a wide range of other things. When fall comes and berries ripen, it is the time to eat berries. In areas where blueberries are abundant, a bear is likely to spend long hours in blueberry fields, gorging itself. Do I need to repeat that most berries are pollinated by insects?


The many herbivores, deer, bison, skunk, rabbit, may eat mostly wind-pollinated grasses; but they also need other nutrients that can only be obtained from flowering plants, from clovers to asters.

Finally, if you are wondering, even meat-eaters benefit from pollinators, since much of their food, the herbivores, feed thanks to them.

Now, we have further reasons to be grateful to pollinators. It isn't just us, humans, who are in their debt, but practically all other animals of our fields and forests.


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© Beatriz Moisset. 2013

Thursday, September 17, 2009

THE WEB OF LIFE. The Bear, the Waxwing and the Bee

You may be wondering what bears, waxwings and bees have in common. We'll get to that later.

Let us start with a black bear, the formidable resident of forests and broad spaces. An encounter with one of them can be an unforgettable experience. It is surprising to realize that an animal built up with such powerful claws and jaws is seldom a hunter; in fact perhaps only 10 or 15 percent of its diet consists of animal matter and a good part of that is carrion or insects. So, what does a bear eat? With great versatility it finds a wide range of plant food in the course of the year. In early spring, fresh out of hibernation it may find skunk cabbage to its liking as well as sprouts from plants in the pea family, horsetails and sedges. Later in the season it will find the growing cow parsnips and dandelions, as well as flowers of several kinds. It may supplement this vegetarian diet with some animal protein, from caterpillars to the occasional newborn elk; but still about 80 percent of the summer diet is vegetable. In the fall, it is the time to feast on berries; blueberries, raspberries and everything in between. It can devour enormous quantities of this food because it needs to fatten for the long winter ahead. It is hard to believe that such diet can become many pounds of fat in the short period of a couple of months.

And now for cedar waxwings, those attractive birds that are so much fun to watch. They are especially interesting when they are engaging in their peculiar tradition of passing berries from one to another. Cedar waxwings eat an assortment of berries through the year. In summer, when they are raising young, they enrich their diet with insects; but berries are the main staple of their diet.

Finally, let us talk about bees. Let us make it clear that I am not referring to the domestic honeybee but to any of the numerous native bees and bumblebees that feed on pollen and nectar of wild flowers. If we want to be more specific we can choose the blueberry bee. This industrious little bee is very specialized on the pollen it chooses to feed her family. It goes almost exclusively to blueberry flowers. When doing so it carries some pollen from flower to flower and from plant to plant, providing the plant an invaluable service, pollination. Once the flowers are pollinated they can start setting seeds and developing fruits.

Now, you see the link between bees and birds such as the cedar waxwing and larger animals such as the black bear. They feed on the berries that have been pollinated by the bees or, in the case of the bear, on other plant parts that also require pollination to multiply.

Experts on pollination remind us frequently that one third of our food comes to us courtesy of pollinators; most fruits and vegetables require the services of these little go-betweens, most of them bees. What they forget to mention is the large number of other species that also depend on pollinators for a good part of their diet. The bear and the waxwing are just two examples of a very long list that intertwines the little bees with the more visible birds and mammals.

Another twist in this intricate web, the bear and the waxwing digest the berries but not the seeds. So they end up dropping them farther from the mother plant and surrounded with an amount of excellent fertilizer. So, the pollinator, in turn, also depends on the seed dispersers.

But the final, and perhaps most marvelous twist, is that the plants, so dependent on pollinators and seed dispersers are actually making use of them. They are very skilled in attracting their attention and supplying their needs, either with rich pollen and nectar or with juicy, nutritious fruits. At the same time, they make sure that not all the pollen gets eaten and that the seeds can safely go through the intestines of the berry gluttons.
Thus the web is complete: flowering plants need the pollinators and the seed dispersers; bees need the flowers and the seed dispersers and, finally, bears and birds need the plants and the pollinators. When you walk through the woods or the meadows, think about this invisible web and what it is doing to make everything possible.

Bear feeding: BearDiet

Cedar waxwing feeding: Appalachian Mountain Club: Bird of a Feather...