The State of the Birds report identifies more than two dozen “common birds in steep decline” — species that are showing early warning signals of distress, having recently lost more than half of their global populations. Mostly, these species are barometers for greater environmental issues. The eastern meadowlark and northern bobwhite are fading from rural America right along with the family farm and its smaller-scale agricultural practices of pasturing cows and keeping grass buffers. Common nighthawks, those fantastic evening acrobats that flash through our ball-field lights to catch bugs on summer nights, are disappearing alongside native pollinators like bees. Many experts suspect that continent-scale declines in the prey of insect-eating birds have resulted from agricultural and homeowner insecticide use.

I suggest that the broader conservation argument transcends cost efficiencies and scientific analyses and should focus instead on the moral questions posed by Martha. Most of us wish we could see those storied passenger pigeon flocks for ourselves, so why aren’t we doing everything possible to keep some of our most common wild things from meeting the same fate? Don’t our great-grandchildren have the right, as part of their American heritage, to experience choruses of meadowlarks singing “spring is here!” from treetops and fence posts?

In the past century, we have built the greatest conservation system in the world. Sadly, the passenger pigeon just missed the dawn of conservation in America. In 1900 the Lacey Act became our nation’s first federal wildlife protection law, and three years later President Theodore Roosevelt saved pelicans and egrets from plume hunters by establishing Pelican Island in Florida as our first national wildlife refuge. Numerous other laws and actions followed, including the Migratory Bird Treaty Act of 1918, which still protects all nongame birds today.

A century after Martha’s death, the results of bold conservation actions are all around us, and are not limited to high-profile birds like falcons and eagles. The State of the Birds report shows that wetland birds altogether have increased significantly since 1968. The reason for this growth of waterfowl populations like the mallard, blue-winged teal and gadwall dates from the 1930s, when federal laws established the Migratory Bird Hunting and Conservation Stamp Act and an excise tax on firearms and ammunition to provide funding for wildlife management and habitat protection.

The report’s population indicators also identify habitats where conservation investments are desperately needed today. “Aridland” birds of the American desert, chaparral and sagebrush — such as the sage grouse, gilded flicker and black-throated sparrow — have declined by nearly half since 1968. These declines, driven primarily by habitat loss and fragmentation owing to energy and residential development, have been exacerbated recently by severe drought. Drive along our iconic Western desert highways and you may not notice anything unusual, but it’s a bird habitat in crisis.

Why should we care about these aridland birds, or any birds? It’s a common question, as elected officials and voters weigh conservation investments alongside health care, immigration and economic issues.

Besides our moral imperative to maintain the earth’s beauty and bounty for future generations to enjoy, it is important to view birds as accessible indicators of the health of our lands and waters. Take those declining meadowlarks as one example: In my home state of Minnesota, where meadowlarks commonly sang atop utility poles back in the 1950s, the patches of wild grasslands they depended on are now horizon-to-horizon farm fields. As a consequence, barges now get stuck in sediment-filled portions of the Mississippi River because grasslands no longer intercept silt-laden runoff waters from farms. The toxic algae bloom in Lake Erie that recently rendered Toledo’s water supply undrinkable had a similar origin. In short, healthy bird habitat makes for healthy human habitat.