Grimpar des ruisseaux

En bref

  • Scientific Name: Lochmias nematura
  • Spanish Name: Trepatroncos colifino
  • Family: Furnariidae
  • Known Nicknames: Streamside Woodcreeper, Sharp-tailed Streamcreeper
  • Average Length: 14–15 cm / 5.5–5.9 in
  • Average Weight: 18–24 g / 0.63–0.85 oz
  • Envergure : N/A
  • Key Feature: White-spotted underparts and a sharp, slightly decurved bill
  • Primary Diet: Insectivore (aquatic insects, larvae, spiders)
  • Range: South America: from northern Venezuela and Colombia south to northern Argentina and southeastern Brazil
  • Habitat: Fast-flowing, rocky streams in montane and foothill forests
  • Structure sociale : Solitaires ou en couples
  • Nesting/Breeding: Burrow in a stream bank or among rocks
  • Statut de conservation : Préoccupation mineure (LC)
  • Évolution démographique : Stable

The Sharp-tailed Streamcreeper (*Lochmias nematura*) is a distinctive, thrush-sized bird of South American fast-flowing mountain streams, instantly recognizable by its unique foraging behavior and striking plumage. Its general appearance is a rich, dark brown above with a bold, white-streaked breast and belly, while its most special feature is a stiff, sharply pointed tail used to brace itself against mossy rocks and waterfalls as it creeps along stream edges. True to its name, this bird possesses a slender, slightly decurved bill perfectly adapted for probing into crevices for aquatic insects and larvae, and it is often seen bobbing its tail and head in a characteristic, animated motion. A master of its niche, the Sharp-tailed Streamcreeper is a living embodiment of adaptation, perfectly engineered for life in the turbulent, spray-drenched world of neotropical headwaters.

Faits amusants

Despite its name, the Sharp-tailed Streamcreeper is not a true creeper but an ovenbird, and it has a peculiar habit of bobbing its entire rear end up and down like a mechanical toy while foraging. It possesses an unusually long, stiff tail spine that it uses as a prop against mossy rocks, allowing it to cling vertically to slippery waterfall spray zones without falling. Perhaps its most bizarre adaptation is that it builds a domed nest with a side entrance that resembles a miniature cave, often hidden behind a curtain of dripping water, which serves as both camouflage and a natural air conditioner for its chicks.

Habitats et répartition

This bird is found along the eastern slope of the Andes from northern Venezuela and Colombia south through Ecuador, Peru, and Bolivia, and also across southeastern Brazil, Paraguay, and northeastern Argentina. It inhabits dense, humid montane and lowland forests, almost always in close association with fast-flowing, rocky streams and rivers. Its preferred environment is the dark, wet understory of these riparian zones, where it forages among moss-covered boulders and tangled roots, often in steep, rugged terrain.

Comportements & Reproduction

The Sharp-tailed Streamcreeper is typically solitary or found in mated pairs, defending linear territories along rocky streams. Its breeding season aligns with the rainy period, and pairs construct a distinctive domed nest with a side entrance, often tucked into a bank crevice or under a bridge. Mating appears to be monogamous, with both parents sharing incubation and feeding duties. A unique strategy involves the nest’s hidden placement near running water, which may reduce predation risk. Clutch size is usually two eggs, and the young fledge after about two weeks, remaining dependent on the parents for a short period before dispersing.

Alimentation

The Sharp-tailed Streamcreeper is an insectivore, foraging almost exclusively in the fast-flowing rocky streams and rivers of its South American habitat. Its diet consists primarily of aquatic insect larvae and nymphs, with a strong preference for caddisflies (Trichoptera), mayflies (Ephemeroptera), and stoneflies (Plecoptera). It also consumes small crustaceans, spiders, and terrestrial insects that fall into the water. A fascinating aspect of its feeding behavior is its remarkable adaptation to its environment: it frequently submerges its entire head and neck into the rushing water to pluck prey from underwater rocks, and it can even walk on the stream bottom in shallow, turbulent rapids to capture hidden food. Furthermore, its long, slightly decurved bill is perfectly shaped for probing into crevices between stones, while its strong legs and sharp claws allow it to cling to moss-covered boulders in the spray zone without being swept away.

Couleurs

The Sharp-tailed Streamcreeper has dark brown upperparts with fine pale buff spotting, a long white supercilium, and a whitish throat and underbody heavily streaked with dark brown. Its rufous-brown rump and tail, along with a pale buff eye-ring, provide disruptive camouflage against streambed rocks and leaf litter.