Sanford's sea eagle
|Sanford's sea eagle|
The Sanford's sea eagle (Haliaeetus sanfordi), sometimes listed as Sanford's fish eagle or Solomon eagle, is a sea eagle endemic to the Solomon Islands. The "sea eagle" name is to be preferred, to distinguish the species of Haliaeetus from the closely related Ichthyophaga true fish eagles. The species was described in 1935 by Ernst Mayr who noticed that earlier observers had overlooked it, thinking it was a juvenile of the white-bellied sea eagle.
The Sanford's sea eagle was discovered by and named after Dr Leonard C. Sanford, a trustee for the American Museum of Natural History. The first description was by Ernst Mayr in 1935. It can reach a length between 70–90 cm (28–35 in) and a weight between 1.1–2.7 kg (2.4–6.0 lb). The wingspan is between 165–185 cm (5.41–6.07 ft). It is the only large predator on the Solomon Islands. The eagles inhabits coastal forests and lakes up to an altitude of about 1500 m asl.
The plumage is whitish brown to bright brown on the head and the neck. The underparts are brown to reddish brown and dark brown. The upperparts are darkish brown to gray-black. The eyes are bright brown. Uniquely among sea eagles, this species has an entirely dark tail throughout its life.
The breeding season is from August to October. The nest consists of two eggs.
The diet consists of mainly of tideline carrion, fish, molluscs, crabs, tortoises, and sea snakes, and more rarely birds and megabats snatched from the rainforest canopy. It has also been reported to feed opportunistically on the northern common cuscus.
It forms a superspecies with the white-bellied sea eagle. As in other sea eagle species pairs, the other taxon is white-headed. These two are genetically very close, it seems; their lineages separated not longer ago than 1 mya, probably only in the Middle Pleistocene, a few 100,000 years ago.[page needed] Both share a dark bill, talons, and eyes with the other Gondwanan sea eagles.
This eagle is often illustrated on postage stamps of the Solomon Islands.
- IUCN Red List 2012.
- Mayr, E (1936). "Birds collected during the Whitney South Sea Expedition. 31, Descriptions of twenty-five species and subspecies". American Museum Novitates (828): 1–20. hdl:2246/3965.
- del Hoyo, Elliott & Sargatal 1994, p. 121.
- Heinsohn 2000, pp. 245–246.
- Wink, Heidrich & Fentzloff 1996.
- Note that Wink et al's reservation about the high rate of molecular evolution have proven well justified; the 2% per 4 million years seem if anything an overestimate. In addition, as the provenance of specimens is not noted, genetic introgression due to hybridzation cannot be excluded, as the species' ranges touch. This is unlikely due to marked differences in behavior and habitat preferences however.
- BirdLife International (2012). "Haliaeetus sanfordi". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
- "Species factsheet: Sanford's Sea-eagle Haliaeetus sanfordi". birdlife.org. BirdLife International. 2011. Retrieved 2011-05-25.
- Cited works
- del Hoyo, J.; Elliott, A.; Sargatal, J., eds. (1994). Handbook of the Birds of the World 2. Barcelona: Lynx Edicions. ISBN 84-87334-15-6.
- Heinsohn, Tom (2000). "Predation by the White-breasted Sea Eagle Haliaeetus leucogaster on phalangerid possums in New Ireland, Papua New Guinea". Emu 100 (3): 245–46. doi:10.1071/MU00913.
- Wink, M.; Heidrich, P.; Fentzloff, C. (1996). "A mtDNA phylogeny of sea eagles (genus Haliaeetus) based on nucleotide sequences of the cytochrome b gene" (PDF). Biochemical Systematics and Ecology 24 (7–8): 783–791. doi:10.1016/S0305-1978(96)00049-X.