Old Man Winter has finally relaxed his grip on a landscape that’s been frozen for, well, a long time.

If that isn’t enough good news, consider this: Tomorrow we will receive about four more minutes of daylight than today.

Changes like these mean outdoors people like us can finally enjoy a multitude of pleasurable springtime outings. For me, one of those annual activities is to maintain my wood duck nesting boxes. Now is the best time while the ponds are still frozen, before the creatures settle in Minnesota to raise their young. I want to have my nesting boxes in tiptop shape when the first wood ducks arrive in the coming weeks.

For about two decades I’ve been monitoring and maintaining a dozen or so wood duck nesting boxes, placed on my property south of Brainerd. Wood ducks, as well as other cavity-nesting species like hooded mergansers and kestrels, have successfully raised families in the wooden homes I have provided for them.

Until a few years ago, my wood duck nesting boxes were attached to tree trunks. During my spring maintenance I often had to evict a critter or two. Gray squirrels were the most common residents, with deer mice a close second. I would simply toss out their bedding material and replace it with wood shavings.

Now my wood duck nesting boxes are mounted on posts, which are attached with metal cones to act as predator guards. I adopted the plan endorsed by the Wood Duck Society. Check out its website at www.woodducksociety.com for complete instructions and patterns for building and placing predator-proof nesting boxes. The website also provides information on where to purchase the metal cones and brackets.

When my wood duck boxes were mounted to trees, I occasionally had trouble with predators invading my boxes. The culprits were mostly raccoons. But in recent years, the fisher, a mink-like animal, has become relatively common in central Minnesota, and they became a real problem, not only entering my boxes and destroying the eggs but killing the hen wood duck, too. Despite their name, fishers rarely eat fish. They are agile predators and can climb trees like a red squirrel.

I am not anti-predator. Predators belong in our fields and forests just like any other species. When kept in check, predators are a necessary component of a healthy ecosystem. But I refuse to provide them with easy access to a smorgasbord of wood ducks and wood duck eggs.

In the coming days I’ll wander my land from box to box with a bag of pine shavings in hand. If I see that the box was used last spring, I’ll simply remove the egg shells and egg membranes, throw out the duck down and replace or add new wood shavings to a depth of 4 or 5 inches.

Then I’ll double-check that the box is mounted securely to the post and, if necessary, perform some simple maintenance such as tightening screws.

Placing and monitoring wood duck nesting boxes is rewarding and a great way to get up close and personal with this splendid waterfowl species.

Bill Marchel, an outdoors writer and photographer, lives near Brainerd.