When does migration bring new birds to Colorado? I’ve been pondering that question ever since I started birding. As a gardener with years of experience, I know when to plant each crop or flower. I know that 70° afternoons can be followed by 3° nights. Yes, April is like that—don’t be fooled.

But migration varies from species to species, and even sometimes from year to year. Instead of learning when to set out a dozen veggie varieties, I have to become familiar with the timing of hundreds of birds. For the most part, that’s still a huge mystery to me.

The best way to learn is by experience, so now that we’re back from California I’m doing my best to spend lots of time out in the field birding. (Even in California, I discovered that several of my target species hadn’t flown into town yet, while most of the winter birds were fast disappearing to the north.)

When I can’t get away, I peek out the window on a regular basis to see who’s hanging around my yard at home. Past years have taught me that Broadtailed Hummingbirds (right) will arrive at my feeders sometime between April 29 and May 1, regardless of the weather. Pretty remarkable! And bluebirds have been in town since March. That’s two species, but what about other birds?

Just when do the juncos leave, and the Chipping Sparrows (right) arrive? The Pine Siskins have been at my nyjer feeder all winter; when did those Lesser Goldfinches join them? One day I’ll notice a Black-headed Grosbeak—has it been there for a while or did it just arrive? I’m trying hard to pay more attention, to note it on my calendar in the same way I keep a record of first and last frosts, when my carrot seeds germinate, or the first ripe tomato.

While this information is inherently interesting, at least to birders, there’s a practical aspect as well. If I want to see migrating warblers, I might drive the hour to Chico Basin Ranch (southeast of Colorado Springs), then pay the $15 entry fee. But I don’t want to go to the effort and expense unless I know that there’s a good chance the warblers will be around.

Until I build up my own expertise, there are a few places I can turn for guidance. Most regional birding books (such as the now outdated Birder’s Guide to Colorado, by Harold R. Holt) have charts in the back showing when various species are present and in what level of abundance. Our local Audubon chapter’s field trip destinations and target birds are further clues. Plus, I can always ask more experienced birders for input.

Unfortunately, sometimes even the “experts” get it wrong. One year, Pete and I drove out to the southeastern corner of Colorado the week after the High Plains Snow Goose Festival, hoping to get some photos. We didn’t see a single goose. When I asked the ranger at John Martin Reservoir, he laughed and told us that the best time to see wintering Snow Geese was between Christmas and New Year’s—even though the festival was in late February! Live and learn.

I have high hopes for this year. My friend Debbie (another avid birder/photographer) and I plan to camp at the Black Canyon of the Gunnison National Park at the end of April in order to catch displaying grouse and nesting raptors. We’re planning a trip out to Chico Basin Ranch a week later, for those migrating warblers I mentioned above. And two weeks after that is the Colorado Field Ornithologists’ yearly convention, this year to be held in Cortez, in the southwest corner of the state. Their field trips usually provide me with at least one new bird plus hundreds of photos.

Everyone knows that the Cliff Swallows return to Capistrano on March 19, but there’s no hotline to call if I want to know when goldfinches will finally turn a photogenic yellow (unlike this American Goldfinch, left). I want to take pictures of baby prairie dogs (yes, I know they’re not birds, but they’re cute), but I can’t seem to discover when they have their litters. And if I want to see fluffy Great Horned Owlets (above), when should I search the cottonwoods? Only experience will teach me these things. Gee, another great reason to get out and go birding!