[order] PROCELLARIIFORMES | [family] Procellariidae | [latin] Pterodroma heraldica | [authority] Salvin, 1888 | [UK] Herald Petrel | [FR] Petrel de la Trinite du Sud | [DE] Trinidadsturmvogel | [ES] Petrel de la Trinidade | [NL] Salvins Stormvogel
| Genus |
Species |
subspecies |
Region |
Range |
| Pterodroma |
heraldica |
|
PO |
sw |
Genus
Genus Pterodroma, Pseudobulweria and Aphrodroma are also knwon as the Gadfly Petrels. They vary in size from rather small birds such as the Cookilaria-species, measuring about 26 cm, to the much larger and robust representatives of this group like the White-headed Petrel with an overall length of about 43 cm. Their plumages also vary a great deal from species to species; from completely black to light grey mantles and pure white bellies, and with different color phases within species. One feature shared by all of them is the black bill of which the shape also shows much variation. Some species are extremely rare and restricted to a very limited area, other are abundant and wander widely or have unknown pelagic ranges.
The group of the Gadfly Petrels counts over 35 species, mainly from the Southern Hemisphere. There are three genera: Pterodroma with about 30 species, Pseudobulweria counting four and Aphrodroma with only one. Many authors have tried to classify the large number of species of this group and to determine their relationships. This has resulted in a division in several subgenera and the grouping of several species which are considered to have a more or less close relationship. The taxonomic discussion has not come to an end yet: new species have been added or split recently and probably will be in the near future.
Medium petrel, three color morphs: light, intermediate, dark. Dark morph is dark gray overall, silver-gray to white base on underwing flight feathers. Light morph has white breast, belly and dark gray upperparts. Intermediate forms exist between light and dark morphs. Gray legs, feet.
Listen to the sound of Herald Petrel
[audio:http://www.planetofbirds.com/MASTER/PROCELLARIIFORMES/Procellariidae/sounds/Herald Petrel.mp3]
Copyright remark: Most sounds derived from xeno-canto
recorded by Alvaro Jaramillo
| wingspan min.: |
88 |
cm |
wingspan max.: |
102 |
cm |
| size min.: |
35 |
cm |
size max.: |
39 |
cm |
| incubation min.: |
49 |
days |
incubation max.: |
54 |
days |
| fledging min.: |
0 |
days |
fledging max.: |
0 |
days |
| broods: |
1 |
|
eggs min.: |
1 |
|
| |
|
|
eggs max.: |
1 |
|
Pacific Ocean : Southwest. The Herald Petrel is found predominately in the central and western Pacific, breeding on Raine Island (Australia), east to Easter Island (Chile). Two further colonies are found at Round Island (Mauritius) in the western Indian Ocean, and at the Trindade and Martim Vaz Islands, Brazil. Individuals have been recorded as far north as the Hawaiian Islands (USA) in the Pacific, and off the coast of northern Argentina in the Atlantic. This marine species is highly pelagic, rarely approaching land except at colonies. Its breeding season is variable depending on location, with adults visiting colonies formed on oceanic islands, atolls or offershore stacks almost all year round. Colonies are loose, with nests being made in rocky crevices, on crags or on the ground up to 1000 m above sea level.
This marine species is highly pelagic, rarely approaching land except at colonies. Nests are being made in rocky crevices, on crags or on the ground up to 1000 m above sea level.
Monogamous pair bond. They breed in loose colonies. One white egg is laid in a rock cervice or burrow which is excavated or cleaned out by both sexes. For their breeding grounds Herald petrels choose warm islands and do not line burrows with any nest materials. Incubation ranges from 49 to 54 days and is carried out by both parents.
Very little is known about its diet, though squid have been recorded
httpv://www.youtube.com/watch?v=VpsEjKx0Ais
copyright: Peter Fraser
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). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very 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 population is suspected to be in decline owing to predation by invasive species.
Adults apparently fairly sedentary in much of range; immatures may be more mobile, dispersing over tropical and subtropical waters of Atlantic, Indian and Pacific Oceans; colonies at Raine I deserted Nov-Jan. In North Pacific occurs mainly Oct-Jan, recorded North to 39 degrees North; in N Atlantic often seen after storms, recorded N to 42 degrees N.
