Corsican nuthatch

Sitta whiteheadi

Photo by Daniele Occhiato (PBase)

Common name:
Corsican nuthatch (en); trepadeira-corsa (pt); sitelle corse (fr); trepador corso (es); Korsenkleiber (de)

Taxonomy:
Order Passeriformes
Family Sittidae

Range:
This species is endemic to the French island of Corsica, in the Mediterranean.

Size:
These birds are 11-12 cm long and have a wingspan of 21-22 cm. They weigh 11-14,5 g.

Habitat:
The Corsican nuthatch is mostly found in mature stands of Corsican pine Pinus nigra laricio
with abundant dead and rotting trunks for nest sites, at altitudes of 1.000-1.500 m. They can also be found in forests where Corsican pine is associated with maritime pine P. pinaster, balsam fir Abies alba or beech Fagus sylvatica, and even in holm oak Quercus ilex and sweet chestnut Castanea sativa forests, gardens and orchards, at altitudes ranging 600-1.700 m.

Diet:
They mainly eat pine seeds, but also small arthropods including adult and larval insects and spiders. They are known to hide pine seeds among bark and lichens when they are more abundant, in order to eat them when the pine cones are closed.

Breeding:
Corsican nuthatches breed in April-July. They nest in tree cavities, either digging the hole themselves or using old nests of the great spotted woodpecker Dendrocopus major. The nest is 2-30 m above the ground. The female lays 4-6 white eggs with reddish-brown markings, which she incubates alone for 14-17 days. The chicks fledge 22-24 days after hatching. Each pair can raise 2 broods per season.

Conservation:
IUCN status - VU (Vulnerable)
This species has a small breeding range and the global population is estimated at just 3.100-4-400 individuals. The population is estimated to have declined by 10% over the last decade, mainly due to forest fires and logging. Since they mostly use the larger and older trees for nesting, logging regimes limit the availability of breeding territories, while forest fires have a destructive effect on their habitat. Climate change may also cause an increase in fire frequency and intensity and so could be a serious future threat to the species, while also increasing potential inter-specific competition between Corsican pine and maritime pine which could have a negative effect on the species range.

Red-breasted nuthatch

Sitta canadensis

Photo by Wolfgang Wander (Wikipedia)

Common name:
red-breasted nuthatch (en); trepadeira-azul-do-Canadá (pt); sittelle à poitrine rousse (fr); trepador canadiense (es); Kanadakleiber (de)


Taxonomy:
Order Passeriformes
Family Sittidae


Range:
These birds are found throughout southern and north-western Canada as well as in the western and north-eastern United States. Some population migrate south to winter throughout the United States and sometimes down to northern Mexico.


Size:
They are 10-12 cm long and have a wingspan of 18-22 cm. They weigh 8-13 g.


Habitat:
Red-breasted nuthatches are mostly found in dense coniferous forests, such as balsam fir, spruce, pine, hemlock, larch, and western red cedar. They can also be found in mixed coniferous-deciduous forests and along riverine forests. During irruptive winters they may even be found in orchards, scrubs, parks, plantations, and shade trees. This species is present from sea level up to an altitude of 3.100 m.


Diet:
During the spring and summer, these birds eat insects and other arthropods, namely beetles, caterpillars, spiders, ants, and earwigs. In autumn and winter they mostly eat conifer seed. During outbreaks of the spruce budworm this becomes an important prey item.


Breeding:
Red-breasted nuthatches breed in May-July. They are monogamous and nest in holes in trees, sometimes using old woodpecker nests or nest boxes. The inside of the nest is lined with grasses, mosses, rootlets, shredded bark, and plant fibers. The female lays 2-8 white or pinkish eggs with brown speckles, which she incubates alone for 12-13 days. The chicks are fed by both parents and fledge 18-21 days after hatching. Each pair raises a single brood per year.


Conservation:
IUCN status - LC (Least concern)
This species has a very large breeding range and the global population is estimated at 18 million individuals. The population has undergone a large increase of 24% per decade over the last 4 decades.