House sparrows have lived happily for thousands of years in Europe and Asia; it was when people brought house sparrows to the United States to help against insect pests that the conflict began, and all because of a misunderstanding.

Who has not been dazzled as they walk along some shallow watery shore by the sight of a 4-foot-tall great blue heron standing almost motionless? We have many that make their home here in Cambridge, and they are fascinating to observe.

Everyone knows robins – the most abundant bird in North America. (There are 370 million of these guys!) But there’s a lot to know about them that may surprise you.

The downy woodpecker is the smallest woodpecker in North America – 6 inches long, and weighs less than an ounce – but the most common, and John James Audubon considered it the most industrious. Why do they drum, anyway? And how is they don’t hurt themselves?

The Continental Congress put an American bald eagle on the country’s official seal with in 1782, when there were an estimated 50,000 nesting pairs in the United States. But not everyone adored eagles, and by 1963 the lower 48 states was down to only about 417 nesting pairs of the raptors. Here’s how that happened, and what’s happened since.

In the United States, the most famous groundhog prognosticator is Punxsutawney Phil, who every year in western Pennsylvania makes his weather prediction to great ceremony and media attention. You are more likely to be accurate by expecting the opposite of whatever Phil predicts.

People first brought exotic mute swans to North America in the 1870s to decorate country estates, city parks and zoos, and those we see in Massachusetts today are probably descended from birds that escaped from New York – now considered an invasive species by many and huntable in most states.

Where have all the eastern cottontail rabbits gone in the past several weeks? Why do rabbits have such large ears? Why won’t you won’t see references to “rabbits” in works before the 18th century? There’s a lot to know about our urban rabbits and their relatives.

In this tale of two kinds of wildlife, Thomas Morton created a colony like no other in the North America of the 1600s – opposed to slavery, rejecting religious conservatism and filled with pleasure – then wrote the first book banned in the Americas. One volume had the first recorded documentation of the green-winged teal in the future Massachusetts.

Can we thank or blame one Shakespeare buff named Eugene Schieffelin for all the starlings in America? Maybe not. But they’ve been cast in a villainous role by officials who have spent millions of dollars trying to eradicate them — and must curse the name of Schieffelin and others who thought like him in the 1800s.