The island scrub jay (''Aphelocoma insularis''), also known as the island jay or Santa Cruz jay, is a bird in the genus, ''

Aphelocoma The passerine birds of the genus ''Aphelocoma'' include the scrub jays and their relatives. They are New World jays found in Mexico, western Central America and the western United States, with an outlying population in Florida. This genus belong ...

'', which is

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 elsew ...

Santa Cruz Island Santa Cruz Island (Spanish: ''Isla Santa Cruz'', Chumash: ''Limuw'') is located off the southwestern coast of Ventura, California, United States. It is the largest island in California and largest of the eight islands in the Channel Islands a ...

off the coast of

Southern California Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural region that generally comprises the southern portion of the U.S. state of California. It includes the Los Angeles metropolitan area, the second most po ...

. Of the over 500 breeding bird species in the continental

U.S. The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

and

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

, it is the only insular endemic landbird species.

Description

The island scrub jay is closely related to the

California scrub jay The California scrub jay (''Aphelocoma californica'') is a species of scrub jay native to western North America. It ranges from southern British Columbia throughout California and western Nevada near Reno to west of the Sierra Nevada. The Cali ...

(the coastal population found on the adjacent mainland), but differs in being larger, more brightly colored, and having a markedly stouter bill. They will bury, or cache, the acorns in the fall and may eat them months later. They also eat insects, spiders, snakes, lizards, mice and other birds' eggs and nestlings.

Taxonomy

The island scrub jay was first described by American

ornithologist Ornithology is a branch of zoology that concerns the "methodological study and consequent knowledge of birds with all that relates to them." Several aspects of ornithology differ from related disciplines, due partly to the high visibility and th ...

Henry Wetherbee Henshaw Henry Wetherbee Henshaw (March 3, 1850 – August 1, 1930) was an American ornithologist and ethnologist. He worked at the U.S. Bureau of Ethnology from 1888 to 1892 and was editor of the journal ''American Anthropologist''. Biography Early l ...

in 1886 and an archaeological specimen at site SCRI-192 dating from the 1780s-1812 on Santa Cruz Island is the earliest evidence of the bird in the historic period. This bird is a member of the

crow family Corvidae is a cosmopolitan family of oscine passerine birds that contains the crows, ravens, rooks, jackdaws, jays, magpies, treepies, choughs, and nutcrackers. In colloquial English, they are known as the crow family or corvids. Currently, ...

, and is one of a group of closely related North American species named as scrub jays. These were formerly treated as a single species, the scrub jay (as ''Aphelocoma coerulesens''), with five

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

, but are now considered four species: the

Florida scrub jay The Florida scrub jay (''Aphelocoma coerulescens'') is one of the species of Aphelocoma, scrub jay native to North America. It is the only species of bird Endemism in birds, endemic to the U.S. state of Florida and one of only 15 species endemic ...

(''A. coerulescens''), the island scrub jay, the

(''A. californica''), and

Woodhouse's scrub jay Woodhouse's scrub jay (''Aphelocoma'' ''woodhouseii''), is a species of scrub jay native to western North America, ranging from southeastern Oregon and southern Idaho to central Mexico. Woodhouse's scrub jay was until recently considered the sam ...

(''A. woodhouseii''). DNA studies indicate that the island and coastal forms have long been isolated from their relatives inland. The relationships within the genus have been studied in several papers (e.g. ) Island scrub jays seem to be incapable of crossing significant bodies of water. Reliable historical observer records for island scrub jays in addition to Santa Cruz Island include only a single 1892 account on neighboring Santa Rosa Island, only about 10 km (6 mi) away. There are no definite occurrences of a scrub-jay on any other of the Channel Islands, or on the

Coronado Islands The Coronado Islands (''Islas Coronado'' or ''Islas Coronados''; en, Islands of the Coronation(s); Kumeyaay: Mat hasil ewik kakap) are a group of islands located off the northwest coast of the Mexican state of Baja California. Battered by the w ...

, only 13 km (8 mi) from the mainland. The historic observation on Santa Rosa Island is supported by an archaeological record of a single island scrub jay femur from a Late Pleistocene-Holocene site (SRI-V-3). Early studies suggested that the ancestor of the present population was storm-borne or carried on driftwood to Santa Cruz, or that the colonization occurred during a period of

glaciation A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate betw ...

70,000 to 10,000 years ago, when sea levels were much lower and the channel between the coast and the islands was correspondingly narrower.Atwood, Jonathan L (1980) Breeding biology of the Santa Cruz Island Scrub Jay, pp. 675–688 in More recent DNA studies show that, although other island endemics such as the

island fox The island fox (''Urocyon littoralis'') is a small fox that is endemic to six of the eight Channel Islands of California. There are six subspecies, each unique to the island it lives on, reflecting its evolutionary history. They are generally do ...

and the

Santa Cruz mouse The Santa Cruz mouse (''Peromyscus sejugis'') is a species of rodent in the family Cricetidae. It is endemic to Mexico, where it is found only on two small islands in the southern Gulf of California. Feral cats on Santa Cruz Island are a threat. ...

may have diverged from their mainland relatives around 10,000 years ago, the scrub jays separated in a period of glaciation around 151,000 years ago. The most recent analysis indicates that the island scrub jay has been evolving in isolation for approximately one million years, i.e. over multiple glacial cycles. Up to about 11,000 years ago, the four northern Channel Islands were one large island, so island scrub jays must have been present on all four islands initially, but became extinct on Santa Rosa, San Miguel and Anacapa after they were separated by rising sea levels.

Distribution and habitat

The island scrub jay is found only on

, the largest of California's Channel Islands with an area of 250 km² (96 mi²). The island is a

nature reserve A nature reserve (also known as a wildlife refuge, wildlife sanctuary, biosphere reserve or bioreserve, natural or nature preserve, or nature conservation area) is a protected area of importance for flora, fauna, or features of geological or ...

, the eastern 24% being administered by

National Park Service The National Park Service (NPS) is an agency of the United States federal government within the U.S. Department of the Interior that manages all national parks, most national monuments, and other natural, historical, and recreational propertie ...

as the part of the

Channel Islands National Park Channel Islands National Park consists of five of the eight Channel Islands off the Pacific coast of the U.S. state of California. Although the islands are close to the shore of the densely populated state, they have been relatively undevelope ...

and the rest of the island by the

Nature Conservancy The Nature Conservancy (TNC) is a global environmental organization headquartered in Arlington, Virginia. it works via affiliates or branches in 79 countries and territories, as well as across every state in the US. Founded in 1951, The Natu ...

. Retrieved 20 May 2012. Fossil remains for island scrub jays have been found on Santa Rosa and San Miguel Islands. Island scrub jays occur in oak chaparral and bishop pine (''

Pinus muricata ''Pinus muricata'', the bishop pine, is a pine with a very restricted range: mostly in California, including several offshore Channel Islands, and a few locations in Baja California, Mexico. It is always on or near the coast. In San Luis Obispo ...

'') woodland on Santa Cruz Island. Island scrub jays in pine habitat have longer, shallower bills than individuals in oak habitat; variation in bill shape is heritable, and individuals mate nonrandomly with respect to bill morphology.

Breeding

Females lay 3 to 5 eggs. Incubation lasts approximately 20 days. These jays are generally monogamous and, unlike some other jays, are not cooperative breeders. Both sexes build a nest to above the ground. Further details in.

Etymology

The genus name, ''Aphelocoma'', comes from the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

ized

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...

''apheles-'' (from ἀφελής-) "simple" + Latin ''coma'' (from Greek ''kome'' κόμη) "hair", in reference to the lack of striped or banded feathers in this genus, compared to other jays. The species name, ''insularis'', comes from the

for "from an island".

Conservation status

The island scrub jay is classed as vulnerable on the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

because its small range makes it potentially vulnerable to a catastrophic incident such as disease or a large fire that destroys their habitat. Population size in 2008 and 2009 was estimated to be 1700 - 2300, making this one of the rarest songbird species in the United States. The entire range of island scrub jays is currently protected in Channel Islands National Park and the species is not at imminent risk of extinction. However, the establishment of

West Nile virus West Nile virus (WNV) is a single-stranded RNA virus that causes West Nile fever. It is a member of the family ''Flaviviridae'', from the genus ''Flavivirus'', which also contains the Zika virus, dengue virus, and yellow fever virus. The virus ...

(WNV) in southern California in 2003 may pose a threat if it crosses to Santa Cruz Island from the mainland.

Corvid Corvidae is a Cosmopolitan distribution, cosmopolitan family (biology), family of oscine passerine birds that contains the crows, ravens, rook (bird), rooks, jackdaws, jays, magpies, treepies, choughs, and nutcracker (bird), nutcrackers. In coll ...

s are especially vulnerable to WNV. In addition, the increased occurrence of wildfires in southern California may portend a catastrophic fire there. Shrub cover has increased since the removal of

sheep Sheep or domestic sheep (''Ovis aries'') are domesticated, ruminant mammals typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus ''Ovis'', in everyday usage it almost always refers to domesticated s ...

(1980–91) and

feral pig The feral pig is a domestic pig which has gone feral, meaning it lives in the wild. They are found mostly in the Americas and Australia. Razorback and wild hog are Americanisms applied to feral pigs or boar-pig hybrids. Definition A feral pi ...

s (2005–07) from Santa Cruz Island, which may increase the fire risk. Overgrazing by non-native

ungulate Ungulates ( ) are members of the diverse clade Ungulata which primarily consists of large mammals with hooves. These include odd-toed ungulates such as horses, rhinoceroses, and tapirs; and even-toed ungulates such as cattle, pigs, giraffes, cam ...

s may have caused extirpation of island scrub jays on Santa Rosa Island. Re-establishing a second population of island scrub jays on Santa Rosa Island may accelerate the restoration of native plant and tree species because of the scatter-hoarding seed caching behavior of ''Aphelocoma'' species.

Human interaction and uses

The

Chumash people The Chumash are a Native American people of the central and southern coastal regions of California, in portions of what is now San Luis Obispo, Santa Barbara, Ventura and Los Angeles counties, extending from Morro Bay in the north to Malibu ...

who were the original inhabitants of the northern Channel Islands may have eaten the local scrub jay, or used its feathers for decoration, since they are known to have made feather bands including jay feathers on the Californian mainland. Human activities may have contributed to the presumed extinction of the island scrub-jay from the smaller islands.

References

External links

Island scrub jay
– Smithsonian Migratory Bird Center *Audubon WatchList
Island scrub jay
Retrieved 26 February 2007. {{Taxonbar, from=Q942489

island scrub jay The island scrub jay (''Aphelocoma insularis''), also known as the island jay or Santa Cruz jay, is a bird in the genus, '' Aphelocoma'', which is endemic to Santa Cruz Island off the coast of Southern California. Of the over 500 breeding bird sp ...

Island scrub jay The island scrub jay (''Aphelocoma insularis''), also known as the island jay or Santa Cruz jay, is a bird in the genus, '' Aphelocoma'', which is endemic to Santa Cruz Island off the coast of Southern California. Of the over 500 breeding bird sp ...

Endemic birds of the Western United States Fauna of the California chaparral and woodlands

Native birds of the Western United States Taxobox binomials not recognized by IUCN