The sandhill crane may be the perfect New Jersey rare bird.

They appear frequently enough that sooner or later, bird watchers will encounter them, but erratically enough that even active birders can go years without seeing one unless they track sightings.

Tall as a blue heron but twice its weight, the sandhill crane has an exotic look: fat body with fluffy tail feathers, the posture of a bird of the plains and a red crown.

Sandhills have been seen in the Garden State every year since 1992. They showed up in seven months during 2009, but sometimes for only a day before moving on.

On Nov. 10, for example, three cranes were found in a puddle near the Leed's Avenue school in Pleasantville.

That trio of sandhills may have been the ones that subsequently appeared in Somerset County the next month and then Franklin Township right before Christmas.

They may have split up in early January, when two were seen in Winslow Township, Camden County, and another in Mercer County.

By mid-January, two sandhill cranes - probably the same two - settled into the area around Cape May, where they've been seen regularly since then.

The pair has been observed working farm fields north of West Cape May, but they have also been seen at the Villas Wildlife Management Area and on marshes in the area.

Sandhill cranes call three-quarters of North America home, and they are the most abundant crane in the world.

Sandhill cranes have another distinction unique among birds: They are the oldest known surviving bird species, according to the International Crane Foundation. A 10-million-year-old fossil of a crane structurally identical to the sandhill crane was found in Nebraska, which they still call home.

When seen in southern New Jersey, sandhill cranes are usually feeding on roots and crop leftovers in farm fields, plus any mice they catch.

Sandhill cranes' fondness for crops and their abuncance means they are something of a pest for Midwestern farmers, since they are adept at probing the ground for seed corn.

The crane foundation is helping to develop a remedy, treating seed corn to make it distasteful to the cranes, leaving them to eat insects, mice and non-crop plants.

That won't be needed around here, where sandhill cranes remain rare - but regular enough to give lots of bird watchers a thrill.

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