There are 10,999 extant species of birds in the world, according to BirdLife International, a global authority on bird conservation.

These birds exist in varying stages of threat, some no threat at all, others said to be on the edge of extinction.

Birds are tough, ancestors of today's birds being survivors of an event that killed most other life on Earth, the fifth mass extinction 65 million years ago.

The previous four date back as far as 400 million years. Huge excess of carbon dioxide was the cause of three of those, a meteor the fourth. All erased life to a large degree.

Scientific observers say we are living in mass extinction number six, in a proposed era called the Anthropocene — Anthropo relating to humans — because we are the source of the trouble this time. Once again, carbon dioxide is the weapon employed.

Dinosaurs and other large animals died in that fifth extinction. Smaller creatures, including unknown bird species, survived. They thrived in a world of reduced threat and competition.

So, today we are one shy of 11,000 species, all descendants of those survivors, shaped and reshaped by natural selection.

BirdLife is the authority for birds when it comes to the annual Red List compiled by the International Union for the Conservation of Nature, which evaluates the status of most plant and animal species worldwide.

This year one new bird species was added to its list, the spectacled flowerpecker, found in Borneo. Ten more were added when a single species was discovered by genetic examination to actually be two species; five became 10.

The heart of this report is classification, listing birds by the degree to which their lives are threatened. Several species familiar to us are included at various levels of threat. (You can read the full report at

BirdLife has determined that 8,460 species, or 77% of the total, are of  Least Concern. The remaining 2,487 species — 23% — are in trouble to various degrees.

That includes 223 species that are Critically Endangered, at imminent extinction risk. This list includes species for whom status remains in doubt, like the ivory-billed woodpecker (that search is continuing, by the way).

An additional 460 species are labeled as Endangered, with their populations decimated and the risk of extinction high. No species to be seen here are included, except for whooping cranes, making rare stopover visits to Minnesota.

Several species found in Minnesota are in the next classification, Vulnerable. They are lesser prairie chicken, chimney swift, and evening grosbeak, both residents, and these migrants — Sprague's pipit and rusty blackbird.

Vulnerable indicates significant decline on a global scale. There is risk that these birds could drop to a more threatened category.

Near-threatened means a species deserves conservation concern because of diminishing numbers. Minnesota species on that list, either resident, migrant, or occasional visitor, are piping plover, red knot, and golden-winged and cerulean warblers. The latter two nest here.

Fifty-two species worldwide are classified as Data Deficient, so little known about them that status cannot be confirmed.

One species seen and heard here, the wood thrush, known for its lovely song, improved its status. It bumped up from being Near-threatened to being of Least Concern.

Worldwide, five species are listed as Extinct in the wild, existing only in captivity.

Species status influences conservation actions by governments and independent organizations like the Audubon Society or the Nature Conservancy. Status impacts levels of attention paid to the needs of particular species.

Climate is a big factor in status determination, along with our never-ending development, leading to the elimination of habitat.

There are two climate issues, I believe. The first is the ongoing insidious change to an ever-warmer world. The second is the difficulty in recognition of that. This change, slow at the moment, can be hard to recognize.

Essentially, at this point, we are asked to understand and accept. The undeniable changes, the elimination of doubt or question — that will come later.

Lifelong birder Jim Williams can be reached at