The Ryukyu wood pigeon (''Columba jouyi''), otherwise known as the silver-banded or silver-crescented pigeon is an
extinct species of
bird
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...
in the
Columba genus in the family
Columbidae
Columbidae () is a bird family consisting of doves and pigeons. It is the only family in the order Columbiformes. These are stout-bodied birds with short necks and short slender bills that in some species feature fleshy ceres. They primarily ...
. This wood pigeon was
endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...
to the
Laurel forest habitat.
Generality
It is an
extinct species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of
pigeon
Columbidae () is a bird family consisting of doves and pigeons. It is the only family in the order Columbiformes. These are stout-bodied birds with short necks and short slender bills that in some species feature fleshy ceres. They primarily ...
that was
endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...
to islands in the
Okinawa archipelago south-west of the
Japanese mainland. In the Okinawa group, it has been recorded from
Iheyajima,
Izenajima,
Okinawa proper and the nearby islet
Yagachijima. In the
Kerama Retto
The are a subtropical island group southwest of Okinawa Island in Japan.
Geography
Four islands are inhabited: Tokashiki Island, Zamami Island, Aka Island, and Geruma Island. The islands are administered as Tokashiki Village and Zamami Vill ...
to the west of Okinawa, it was found on
Zamamijima
is an island in the Pacific Ocean. It is part of the Kerama Islands group and administered as the village of Zamami in Shimajiri District
is a district located in Okinawa Prefecture, Japan. Modern translation of Shimajiri means "Butt of t ...
, whereas in the
Daitō group, some 300 km to the SE of Okinawa, it occurred on both major islets,
Kita Daitōjima and
Minami Daitōjima. In earlier times, it was most likely also found on other islands near Okinawa, such as
Iejima
, previously romanized in English as Ie Shima, is an island in Okinawa Prefecture, Japan, lying a few kilometers off the Motobu Peninsula on Okinawa Island. The island measures in circumference and covers . As of December 2012 the island ...
. The species' scientific name honors Stejneger's friend, the specimen collector
Pierre Louis Jouy.
Extinction
Like all species of Japanese wood pigeons, the Ryukyu wood pigeon was very susceptible to
habitat destruction
Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...
. It required substantial areas of undisturbed subtropical forest to thrive.
Iejima
, previously romanized in English as Ie Shima, is an island in Okinawa Prefecture, Japan, lying a few kilometers off the Motobu Peninsula on Okinawa Island. The island measures in circumference and covers . As of December 2012 the island ...
, for example, was largely deforested for settlement and agriculture even before scientific exploration began, which explains the absence of records from this island. The species was last recorded on Okinawa in 1904, probably succumbing to hunting. In the Daitō group, it disappeared after 1936 due to these small islands being completely deforested by settlement and construction activity prior to
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...
. It was presumed to continue to exist on the outlying islands in the Okinawa group, but has never been found again.
Theoretically, there is sufficient habitat remaining in the mountains of Okinawa. Still, the military activity during World War II and hunting by the Japanese garrison would probably have yielded sightings, if birds still had existed there. More puzzling is the absence of ''any'' records from
Tokashikijima in the Kerama Retto, which, despite being small, has still mostly intact forest cover even today; Zamamijima, where the species is known to have occurred is smaller still and situated farther away from the Okinawan mainland.
References
* Stejneger, Leonhard Hess (1887): Description of a New Species of Fruit-Pigeon (''Janthoenas jouyi'') from the Liu Kiu Islands, Japan. ''
Am. Nat.'' 21(6): 583–584.
External links
Ryukyu Wood Pigeon pictures.
{{Taxonbar, from=Q714093
Columba (genus)
Extinct birds of Oceania
Bird extinctions since 1500
Extinct animals of Japan
Endemic fauna of the Ryukyu Islands
Birds of the Ryukyu Islands
Birds described in 1887