For the Birds: Which Seeds Are Best?
http://www.nwf.org/nationalwildlife/article.cfm?issueID=131&articleId=1769
Condensed by Native Village

 

More than 50,000,000 people feed wild birds in the United States. Yet little science has been done about birds'  nutritional needs or which seeds they like. 

“Wild bird feeding is one of our most understudied wildlife management issues,” said David Horn from Millikin. 

David has established Project Wildbird, a 2005–2008 study in which thousands of volunteers  shared observations from their backyard bird feeders. Among the results are that black oil sunflower, white proso millet, nyjer (thistle) seed and sunflower chips are the most highly sought after seeds.

To stay healthy, birds must consume a mix of fats, proteins, carbohydrates and many vitamins and minerals. They require up to 10,000 calories a day -- the same as 155,000 calories for a human!  A bird burns the most calories during flight, the breeding season, and the coldest days, so they make highly efficient choices about what they eat.

A backyard feeder is a great place for birds to forage. The cluster of food is much like a fruit-laden apple tree. But even with feeders, birds eat a wide variety of foods because if the food source runs out, the bird will die.   A study of black-capped chickadees found that even with unlimited feeder food, they find 79% of their daily energy needs from other wild sources.

Birds judge food items for nutrition and quality. Birds often rattle seeds in their bills to weigh and taste them. Then they eat the high quality food and drop the rest to the ground.  So, if you put out old, moldy, or inedible seeds, the birds will eat elsewhere.

Animal nutrition expert Kirk Klasing is studying how birds taste and assess a food's nutrition.  He learned that the animals “mostly taste umami.” Umami is a Japanese term for one of the five basic tastes.  In a bird's case, it's the taste for protein.  This benefits birds because seeds high in protein are nearly always high in fat, It's the fat that provides the energy boost birds need for flight or cold winter nights. It’s possible that birds may taste the fat content of seeds as well.

Project Wildbird also found that favored seeds are high in protein and fat. Other studies show that birds choose seeds that are easy to handle and digest. That makes it easy to quickly consume a lot of food while avoiding predators.  Research show that birds prefer low-quality, easily handled seeds over high quality foods that are bulky and hard to eat. 

Whichever seeds you buy, remember that backyard feeding helps wild birds. Put out high-quality seeds that areas fresh as possible and stored in a dry clean place. In the depths of winter, when their food needs can increase 2,000%, we humans can help birds survive.

Project Wild Bird: www.projectwildbird.org

Animated Graphics: Heather's Animations