''Icthyophaga'' (often misspelled as ''Ichthyophaga'') is a genus of six species of
eagle
Eagle is the common name for the golden eagle, bald eagle, and other birds of prey in the family of the Accipitridae. Eagles belong to several groups of Genus, genera, some of which are closely related. True eagles comprise the genus ''Aquila ( ...
s, closely related to the
sea eagles in the genus ''
Haliaeetus''. In fact, some taxonomic authorities place this genus within ''Haliaeetus''. Both are native to southeastern Asia, from the
Indian subcontinent
The Indian subcontinent is a physiographic region of Asia below the Himalayas which projects into the Indian Ocean between the Bay of Bengal to the east and the Arabian Sea to the west. It is now divided between Bangladesh, India, and Pakista ...
southeast to
Sulawesi
Sulawesi ( ), also known as Celebes ( ), is an island in Indonesia. One of the four Greater Sunda Islands, and the List of islands by area, world's 11th-largest island, it is situated east of Borneo, west of the Maluku Islands, and south of Min ...
. They are smaller than the ''Haliaeetus'' eagles, though overlapping in size with the smaller species of that genus. They share similar plumage, with grey heads grading into dull grey-brown wings and bodies, and white belly and legs. They differ in tail colour, with the lesser fish eagle having a brown tail, and the grey-headed fish eagle having a white tail with a black terminal band, and also in size, with the lesser fish eagle only about half of the weight of the grey-headed fish eagle.
[del Hoyo, J., Elliott, A., & Sargatal, J., eds. (1994). ''Handbook of the Birds of the World'' Vol. 2. Lynx Edicions, Barcelona .]
Taxonomy
The genus was established by
René-Primevère Lesson in 1843, to accommodate a single species, the
grey-headed fish eagle, which is therefore considered as the
type species
In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...
. Lesson used two spellings for its name: ''Icthyophaga'' and ''Icthyiophaga'', but not ''Ichthyophaga''.
Traditionally, this genus was believed to include two species: the
lesser fish eagle and the
grey-headed fish eagle.
Erwin Stresemann
Erwin Friedrich Theodor Stresemann (22 November 1889, in Dresden – 20 November 1972, in East Berlin) was a German naturalist and ornithologist. Stresemann was an ornithologist of extensive breadth who compiled one of the first and most comprehe ...
and
Dean Amadon mistakenly referred to the genus as ''Ichthyophaga'' in their work, and this erroneous usage persisted for a long time. However, the name ''Ichthyophaga'' actually belongs to a
prolecithophoran
turbellaria
The Turbellaria are one of the traditional sub-divisions of the phylum Platyhelminthes (flatworms), and include all the sub-groups that are not exclusively parasitic. There are about 4,500 species, which range from to large freshwater forms mo ...
n
parasite
Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted str ...
in fish established by Syromiatnikova in 1949.
[
In 2005, a molecular systematic study based on ]nuclear
Nuclear may refer to:
Physics
Relating to the nucleus of the atom:
*Nuclear engineering
*Nuclear physics
*Nuclear power
*Nuclear reactor
*Nuclear weapon
*Nuclear medicine
*Radiation therapy
*Nuclear warfare
Mathematics
* Nuclear space
*Nuclear ...
and mitochondrial genes merged this genus into '' Haliaeetus''.International Ornithologists' Union
The International Ornithologists' Union (IOU) is an international organization for the promotion of ornithology
Ornithology, from Ancient Greek ὄρνις (''órnis''), meaning "bird", and -logy from λόγος (''lógos''), meaning "study", ...
resurrected ''Icthyophaga'' with its right name and transferred four species from ''Haliaeetus'' to this genus.
Ecology
As both the common and generic names suggest, both fish eagle and the grey-headed fish eagle feed largely on fish
A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...
, caught mainly in fresh water
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salt (chemistry), salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include ...
on lakes and large rivers, but also occasionally in salt water in estuaries and along coasts.[
]
References
{{Taxonbar, from=Q539162
*
Bird genera
Accipitridae