On a crisp winter day in the Sacramento Valley, there probably is no sight more glorious than a glistening pond or flooded rice field filled with thousands of ducks and other waterfowl.

These flocks are nothing compared to what existed prior to California's Gold Rush, but they still are impressive. Honking, flapping and diving underwater, these birds are a vibrant part of the ecosystem we've managed to protect over the state's history. Despite loss of historic wetlands, more than 230 species of waterfowl and other migrating birds can be found in the Sacramento Valley.

One reason these flocks are so abundant is a healthy supply of food.

Studies have found that wild ducks in the Sacramento Valley, depending on the season, like to feed on grasses, rice seed, midges and other insects. The latter provide the protein they need; the former provides carbohydrates.

Unfortunately, the ducks and geese that reside at urban ponds like McKinley Park have become guinea pigs for an imbalanced diet. As The Bee's Dan Hill reported last week, the McKinley waterfowl are developing a nutritional deficiency called "angel wing" that affects feather development and probably causes other health problems.

The culprit is the same one fueling the human obesity crisis – an imbalanced diet, combined with lack of exercise. Ducks in the wild are constantly on the move, except when feeding on the right mix of proteins and carbohydrates. People are feeding the obese ducks at McKinley Park bag-fulls of white bread, crackers and junk food.

Neighborhood volunteers are trying to change that by posting signs and encouraging park visitors to feed the birds whole grains.

Of course, that would require more local residents to buy whole grains for their own consumption. That's a much more challenging crusade.

Don't get me wrong: I'm heartened to see the public education campaign. A ban on feeding ducks would never work; it would just cause a flap. (Sorry, couldn't resist.) Just look at the faces of young kids when they throw bread into the pond. Some of them are having their first encounter with a wild – or more exactly, feral – animal. You can't put a price on the curiosity unleashed from such encounters.

My only thought is that the public education could go further. Imagine the McKinley Park pond with a display that would educate young and old people about the waterfowl of the Sacramento Valley – their life history, ecological role and diet.

The reason that park ducks are diseased is only partly because of what they eat. It's also because we've lost so much connection with the natural world.

© Copyright The Sacramento Bee. All rights reserved.

• Read more articles by Stuart Leavenworth

Order Reprint