The Guadalupe junco (''Junco insularis'') is a small bird in the

New World sparrow New World sparrows are a group of mainly New World passerine birds, forming the family Passerellidae. They are seed-eating birds with conical bills, brown or gray in color, and many species have distinctive head patterns. Although they share t ...

family that 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 ...

Guadalupe Island Guadalupe Island ( es, Isla Guadalupe, link=no) is a volcanic island located off the western coast of Mexico's Baja California Peninsula and about southwest of the city of Ensenada in the state of Baja California, in the Pacific Ocean. The ...

off the western coast of

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

. Many taxonomic authorities classified it in 2008 as a subspecies of the

dark-eyed junco The dark-eyed junco (''Junco hyemalis'') is a species of junco, a group of small, grayish New World sparrows. This bird is common across much of temperate North America and in summer ranges far into the Arctic. It is a very variable species, much ...

(''Junco hyemalis''). In 2016, it was re-classified as a full species.

Description and ecology

The Guadalupe junco has a dull grayish head with a gray bill and brownish upperparts. Its wings and tail are blackish, though the tail has white edges. Its underparts are white with a

rufous Rufous () is a color that may be described as reddish-brown or brownish-red, as of rust or oxidised iron. The first recorded use of ''rufous'' as a color name in English was in 1782. However, the color is also recorded earlier in 1527 as a dia ...

fringe at the bottom of the wings. It makes a high, sharp ''sik'' and a long series of chipping notes. This bird is today found mainly in the Guadalupe cypress (''

Cupressus guadalupensis ''Cupressus guadalupensis'', the Guadalupe cypress, is a species of cypress from Guadalupe Island in the Pacific Ocean off western North America. Distribution The Guadalupe cypress, ''Cupressus guadalupensis'', is endemic to Mexico, found only ...

'') grove on Guadalupe Island, with a few birds in the remaining Monterey pine (''

Pinus radiata ''Pinus radiata'' ( syn. ''Pinus insignis''), the Monterey pine, insignis pine or radiata pine, is a species of pine native to the Central Coast of California and Mexico (Guadalupe Island and Cedros island). It is an evergreen conifer in the fa ...

'') stands. Around 1900, it was known to utilize almost any

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

for breeding. It ranged over the whole island for feeding then, and indeed still does theoretically, but actually only a handful of flocks exist. A testimony to the adaptability of this junco is the fact that, today, a few birds breed at the seashore in non-native tree tobacco (''

Nicotiana glauca ''Nicotiana glauca'' is a species of flowering plant in the tobacco genus Nicotiana of the nightshade family Solanaceae. It is known by the common name tree tobacco. Its leaves are attached to the stalk by Petiole (botany), petioles (many other ' ...

'') shrubs, since this is dense enough to provide some protection from

feral cat A feral cat or a stray cat is an unowned domestic cat (''Felis catus'') that lives outdoors and avoids human contact: it does not allow itself to be handled or touched, and usually remains hidden from humans. Feral cats may breed over dozens ...

s. The breeding season is from February to June. Three to four eggs are laid in a bulky

cup nest A bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term popularly refers to a specific structure made by the bird itself—such as the grassy cup nest of the American robin or Eurasian bl ...

of dried grass stems, which is either in a depression in the ground or in the lower branches of a tree. The eggs are greenish-white with reddish-brown spots. If food is plentiful, the birds apparently breed twice a year.

Decline to near-extinction

This bird used to be abundant, but now only 50–100 adult birds are thought to survive.

Domestic goat The goat or domestic goat (''Capra hircus'') is a domesticated species of goat-antelope typically kept as livestock. It was domesticated from the wild goat (''C. aegagrus'') of Southwest Asia and Eastern Europe. The goat is a member of the a ...

s (''Capra hircus'') introduced to provide food for fishermen and to start a meat canning plant in the early to mid-19th century became feral and overran the island by the late 19th century, with more than four goats per

hectare The hectare (; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100-metre sides (1 hm2), or 10,000 m2, and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. An acre is a ...

(nearly two per acre) being present around the 1870s.

Domestic cat The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members o ...

s (''Felis catus'') introduced to the island next also became feral and multiplied, and as the habitat was destroyed by the

feral goat The feral goat is the domestic goat (''Capra aegagrus hircus'') when it has become established in the wild. Feral goats occur in many parts of the world. Species Feral goats consist of many breeds of goats, all of which stem from the wild goat ...

s, the feral cats wreaked havoc on the endemic fauna. In 1897, Kaeding found the Guadalupe junco "abundant", but already decreasing due to feral cat predation. Anthony summed up 10 years of occasional visits in 1901 by noting that "...the juncos are slowly but surely becoming scarce." He blamed the interaction of feral goats destroying the habitat and feral cats destroying the birds themselves. Wilmot W. Brown Jr., H. W. Marsden and Ignacio Oroso surveyed Guadalupe throughout May and June 1906, and collected numerous bird specimens for the Thayer Museum – among these a "large series" of the Guadalupe junco. They found the Guadalupe junco "fairly abundant" but, despite the depredations of the feral cats, still "a very tame, confiding little bird" – in other words, unwary of

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

s. The feral goats were all but exterminated by 2006 by the Grupo de Ecologia y Conservacion de Islas and Island Conservation, permitting spectacular regeneration of the native flora. The island was recently protected as a biosphere reserve again by the above groups. As the habitat regenerates and especially if the planned extermination or containment of the feral cats will be undertaken, the remaining Guadalupe juncos will surely find more protected breeding and feeding sites. Indeed, the future of the Guadalupe junco looks better than it did during the 20th century, although it is still precariously close to extinction and could be wiped out by any chance event, such as a violent storm or an introduced disease. 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 ...

, it is classified as

Endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...

Description and ecology

Decline to near-extinction

Footnotes

Further reading