Since many neotropical migrants head south every fall, it is easy to forget that one songbird hangs around to brave Northeast winters – and warm our hearts in the process.

The aptly named golden-crowned kinglet is a small, extremely energetic bird that is currently classified in the family that includes the ruby-crowned kinglet, Old World warblers, and gnatcatchers. However, its differences have caused scientists to question this categorization, especially in relation to the ruby-crowned kinglet.

Golden-crowneds are very hardy, and can withstand temperatures down to 25 degrees below zero. They do this by keeping on the move, constantly foraging for food in their favorite conifer trees. These are useful clues to identifying them – if you catch maddeningly short glimpses of any tiny, rotund ball of feathers high up in a conifer, especially in winter, you can tentatively label it a kinglet until a closer look or its calls can clinch it.

Its signature head plumage is a slim gold patch, surrounded by a thick black border. In males, this patch additionally surrounds a small, bright orange patch; females’ are only yellow.

The bold markings extend to the face. There is a black line that runs across the eye, above which is a bright white stripe. Upper parts are pale green, while the underside is grayish; the wings sport two bold white bars. It has black legs and yellow feet.

Its call is a high seet, often repeated three or more times. This feature is a pretty definitive clue to identification. The only one it might be confused with is the brown creeper’s; however, the creeper is not known to give voice from high up in conifers during winter. The golden’s song, a wiry, tumbling chatter, ends with a chickadee-like call.

Finally, golden-crowneds are known to be tolerant of humans, and may enter cabins and allow themselves to be touched. If nothing else, this trait certainly would endear them to birders.

Its similarly sized relative, the ruby-crowned kinglet, could not be more different. It is not as hardy, and while it may breed farther north than the golden-crowned, it heads to far southern climes early in the fall. The exception to this would be a milder autumn than usual; this year, birders spotted them well into November.

The ruby-crowned is uniformly olive-green with two white wing bars and a white circle around the eye. Their legs are also dark with yellow feet.

Ruby-crowned kinglets’ songs are exceptionally long, loud, and boisterous for such a small bird; it rivals the winter wren, also a small bird of great virtuosity, in this respect. Its call is a dry chit, chit, which may be heard from dense shrubs or the outer branches of deciduous trees. It is also said that they will not forage upside-down, as the golden-crowned does. These are good clues in identifying them.

The ruby crown of this kinglet is not easily seen. The only time it becomes visible, unlike the golden-crowned’s, is when it erects its crest feathers in response to a threat. Then, it resembles a teenager with red-dyed, spiked hair.

It is interesting that both birds – which are among our smallest – lay huge clutches, numbering, on average, eight to 12 eggs.

Go in search of the irrepressible golden-crowned kinglet this winter – you will not be disappointed by its acrobatics or its energy. Then, look forward to the ruby-crowned’s return in the spring.

Chris Corio’s column on birds is published each Saturday. Corio, a volunteer at Fields Pond Nature Center in Holden, can be reached at fieldspond@juno.com