Neotropic Cormorant (Phalacrocorax brasilianus)

Neotropic Cormorant

[order] SULIFORMES | [family] Phalacrocoracidae | [latin] Phalacrocorax brasilianus | [UK] Neotropic Cormorant | [FR] Cormoran vigua | [DE] Olivenscharbe | [ES] Cormoran Bigua | [NL]

Subspecies

Monotypic species

Genus

The cosmopolitan genus Phalacrocorax of the Suliformes family includes thirty-five species frequenting coasts and islands. The face and throat are naked; the bill is long, and the upper mandible much curved at the point, while the lower supports a dilatable membrane which forms a gular pouch. The legs are short, strong, and abdominal, with three toes in front and one behind, all united; the claw of the middle toe is pectinated and probably used to dress the plumage and to free the bird from insect pests. The wings are of moderate length, and the tail-feathers stiff and rigid. Many of the species develop crests or wattles in the breeding season. These birds feed exclusively on fish. All Cormorants, Shags and Darters have a small bone at the back of the skull, the occipital style. This bone is flexibly attached to the skull and is supposed to have a function for the grasping ability of these birds. The ramphotecal coating of the bills of the cormorants are divided in plates, very much like those of the tubenoses, without visible nostrils.

Physical charateristics

Large, dark blackish waterbird with a long, hooked bill and long tail and a long, thin neck. The gular region pointed and dull yellow with a thin, pale border. Often perches with wings spread to dry them, formerly called Olivaceous Cormorant. The gular region is more white during winter. Sexes are similar.

Listen to the sound of Neotropic Cormorant

[audio:http://www.aviflevoland.nl/sounddb/N/Neotropic Cormorant.mp3]

Copyright remark: Most sounds derived from xeno-canto

wingspan min.: 98 cm wingspan max.: 102 cm
size min.: 67 cm size max.: 69 cm
incubation min.: 25 days incubation max.: 30 days
fledging min.: 70 days fledging max.: 30 days
broods: 1   eggs min.: 3  
      eggs max.: 5  

Range

Latin America : widespread,also South USA

Habitat

Basically found at all inland and coastal water surfaces, saline and fresh. Inhabits mangrove forests, coastlines inland marshes and lakes. Can laso be found high in the Andes Mountains.

Reproduction

Neotropic Cormorants are monogamous and breed in colonies. Nests are built on the tops of mostly medium to largesized located bushes up to 50 m inland. Average height at which nests are placed was half a meter. Nest platforms are built of sticks and twigs, and occasionally lined with grass, sea-weed, feathers, shells and seabird bones or carcasses. Nest dimensions are variable. Nearest-neighbour distance varied from 5o to 1 m. The first eggs are laid mid November. Egg laying continues for over six weeks, until the last week of December. Clutch size varies from one to five eggs, with a mean of almost 4. The length of the incubation period is 24-27 days.

Feeding habits

Its diet consists mainly of small fish, but will also eat tadpoles, frogs, and aquatic insects. This cormorant forages for food by diving underwater, propelling itself by its feet. It is also known to forage in groups, with several birds beating the water with their wings to drive fish forward into shallows.

Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be increasing, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
The Neotropic Cormorant Phalacrocorax olivaceus, also referred as P. brasilianus, is widely distributed in the
Neotropical Region. The species ranges from the southern United States of America to Cape Horn at the southern extreme of South America. The Neotropic Cormorant is one of the few cormorant species which occupies both freshwater and marine environments, breeding in inland wetlands, fast-flowing rivers, high-altitude lakes, and on marine
shores and islands.
Neotropic Cormorant status Least Concern

Migration

Mostly sedentary species with some after breeding dispersal. High altitude colonies will migrate to lower areas during winter. Up until the seventies Surinam Cormorants were non breeders, probably vagrants from surroundkng coutnries.

Distribution map

Neotropic Cormorant distribution range map

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