Brown Creeper

The Brown Creeper is an inconspicuous slender brown bird that clings to and also climbs in a vertical spiral fashion up tree trunks. It is a resident of North America roughly south of the 55 parallel extending northward along the BC and Alaskan coast. Its range also extends into Mexico.

Adult Male (spring/summer)

Very small bird. Patterned brown above and white below; bold, buffy band on wings conspicuous in flight from below and above; rump and tail rufous; thin down curved black bill.

Adult Female (spring/summer)

Is similar but the decurved bill is shorter.

Juvenile

Similar to adults but under parts have a light spotting and duller upper parts.

General:

Tiny, cryptic unique species. Length: 12-14cm. Wing: 17-20cm. Weight: 5-10grams.

Behaviour:

The Brown Creeper is solitary or found in pairs, except in winter when it will often join flocks of foraging mixed species. The Brown Creeper eats various insect, larvae, seed and nuts. The tail feathers, 12 stiff and pointed retrices prop the bird in its upright position as it probes the bark on a tree for invertebrates i.e. insects and spiders. The upward spiral path that the Brown Creeper takes while probing for food is characteristic enough to establish its identity. They rarely eat on the ground, but may eat seeds in the winter. The song and call notes are high pitched and difficult for most people to hear. Also the call notes are often confused with those of the Golden crowned Kinglet.

Habitat:

Brown Creepers are tree dwellers preferring closed canopy, moist, mature, mixed forests and also inhabit drier interior forests and scrubby areas where insects, insect larvae can be found along with some berries and fruit. They use large loose- barked (often dead or dying) trees for nesting.

Information:

The Brown Creepers buff streaked brown back and wing coverts edged with buff and tipped white help to break up the bird’s outline and avoid predation when it is clinging flat against a tree by means of its short legs and large curved claws. The nest is often an unusual half-cup shape behind a lose piece of bark that is still an integral part of the tree trunk. it may also be found in dead tree cavities with heights varying from 5 ft. – 50 ft. The nest is built of twigs, moss, and conifer needles and lined with shredded bark plus feathers. The female will do most of the work. Eggs 4 –8 per clutch, white, oval, sparsely flecked reddish brown and wreathed.

Similar species:

Conservation Status:

Brown Creepers are currently listed at a status of Least Concern. Note that deforestation and forest fragmentation will drastically affect this species. Also the loss of trees due to the invasion of exotic insects has taken its toll in the past.

Capture Rates

The Brown Creeper is a resident species favouring closed canopy forests like those on the outskirts of our banding station at Colony Farm. Subsequently, capture rates reflect activity from July through September when post breeding, individuals increase movement by joining mixed foraging flocks.

Molt Summary:

PF: HY incomplete, PB: AHY complete; PA absent.

Preformative molt includes few if any lesser or med covs, and no gr covs or terts, but apparently the rects.

Birds in juvenal plumage are buffier with buffy edging to the wing coverts. The longest primary covert may have larger and more wedged-shaped buffy tips (blue arrow).

This HY bird in August had molted most median and great coverts – the retained buffy fringed feathers illustrated with the red arrows.

Other characteristics such as prominent gape and loosely textured undertail coverts are reliable for ageing birds in juvenal plumage.