Seeing and identifying a particular bird isn't always the only challenge when bird-watching. For some people, simply getting on the site can be difficult.

When it comes to choosing outdoor activities, canes, crutches, walkers, wheelchairs -- or simply aging bodies -- can be limiting factors.

My wife, Jude, and I were at Madera Canyon in southeastern Arizona last year, a good place to find birds. We heard that an Aztec thrush, a stray from Mexico, was being seen half a mile up a trail at canyon's end. The trail was uphill and rock-studded. For various reasons, neither of us was able to take that hike.

Our recent visit to Ohio presented a very different story. We birded at Magee Marsh, a swampy woodland tight against the Lake Erie shore. Spring migrant birds pile up here to rest and feed before crossing the lake.

At one time, birders tromped through the wet and mucky woods, slowly but surely destroying the place they loved. The Ohio Division of Wildlife recognized the problem, and attraction of this place to bird-watchers. The state built a ¾-mile-long, 6-foot-wide boardwalk that snakes through the woody swamp. It has ramps. It has benches. It's a marvel.

What struck me was the number of birders we saw using canes, crutches, walkers and wheelchairs. You don't usually see those folks out birding. We also saw parents with small children in strollers, another population segment with access concerns.

In Minnesota, birders with mobility issues have lots of good places to find and observe birds, places that limit or do away with those issues.

Where are they? All over. And Frank Berdan of St. Paul decided to make a list of them.

Berdan has a 76-year-old friend who walks with a cane. "The problem was that my friend and I didn't know many places we could go birding together," Berdan said.

"We needed locations where mobility-limited folks can safely and productively observe birds, either by foot -- we limited it to a quarter-mile or less -- or by parking somewhere off-road [for birding from car windows].

"We're keen on trail-surface quality. Paved or flat trails with no roots are good. We want to know what species of birds are likely to be observed. And we want to know about any amenities, like restrooms, blinds or boardwalks," he said.

His solution was to ask active birders to nominate suitable locations. He posted his request on the e-mail network of the Minnesota Ornithologists' Union. The list, titled "Short Walks," now contains more than 110 accessible birding locations.

At least 45 are in the metro area, with the rest elsewhere in the state or in Wisconsin. Berdan and eight people who help him with this intend to keep building the list. You can find its website at tiny.cc/x8y58.

As of mid-June, a website counter indicated the page had received 6,857 hits. You can help expand the opportunities. If you know of a suitable location, send an e-mail to Berdan at fberdan3@yahoo.com.

Lifelong birder Jim Williams can be reached at woodduck38@gmail.com. Join his conversation about birds at www.startribune.com/wingnut.