Over the last month or so, the tempo of bird life has changed and undergone a fundamental shift.

The advent of spring brought with it the rush of returning migrants. Neotropical songbirds filled the woods and fields with color and song, and all bird life became obvious in its territorial displays and advertisements for mates.

Once these were established, a relatively quieter period followed. Eggs were laid and the serious business of incubation demanded secrecy and increased foraging for food. Then the young were hatched, and a different kind of frenzy followed: nestlings and fledglings, oblivious of the need for caution, loudly and continuously demanded food. They called attention to themselves first from the nest, and then as they followed their parents about, hungry mouths gaping.

Now, over the last few weeks, the pace has shifted again. The young of the year are learning to fend for themselves and growing more aware of how to stay safe from predators. They and their parents are engaged in the serious business of fattening up for migration. They move quietly through full, leafy vegetation, occasionally emitting small contact calls. They are very hard to see, and many times difficult to identify when they are spotted.

This time is, for many birders, considered a slow and quiet time. Although shorebird migration is getting into full swing, viewing these supreme long-distance migrants pouring down out of the North is largely dependant upon luck and circumstances.

Tides and water levels must be low enough to expose sand and mudflats, enabling the birds to stop, rest, and refuel. Depending upon conditions, the birds may only linger a very short time before continuing on.

The cycle seems to be set, and I think with sadness of the ending of another summer. However, two bird species have been calling themselves to my attention over these last few weeks, reminding me there are exceptions to every rule.

Walking across a field, I hear the signature “per-chic-or-ree,” of a male goldfinch as he performs a deep looping flight through the air. This is a typical display given during the breeding period and is often used to delineate the boundaries of his territory.

American goldfinches breed late in the season, timing their nesting efforts to coincide with the flowering of thistles, an important food source. They may not lay their last egg until now, mid-August. Researchers think their whole-body molt in spring (during which they turn from drab olive to bright yellow) places too much stress on their systems, making early nesting impossible.

Similarly, cedar waxwings also breed late, timing their cycle to coincide with the ripening of sugary summer fruits. I’ve been delighted to be accompanied by their high, lisping call notes as I head out on an afternoon run or to see them perched on the branches of a white pine tree. Their beautiful reddish-brown body feathers, along with their striking black facial masks, shiny red waxy tips on their secondary flight feathers, and bright yellow bands across the ends of their tails make them stand out vividly against the light green of the pine needles.

Both of these birds are year-round residents over much of their breeding ranges. Goldfinches are able to obtain their wild seed diets at any time of the year (as well as readily visit backyard feeding stations containing thistle and sunflower seed), while waxwings switch to a diet of winter fruit, feasting on cedar berries and the fruit of ornamental trees such as crabapple. Because both of these food sources – especially the fruit – can be patchy in distribution, goldfinches and waxwings will become very nomadic, but they won’t have to migrate long distances as do other birds. They can afford to be late breeders.

So, while most other birds are preparing to head south and are, in general, becoming less conspicuous in their appearance and habits, the goldfinches and waxwings are still putting on a show. Summer isn’t quite over yet.

BDN bird columnist Chris Corio can be reached at bdnsports@bangordailynews.net