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 th ...

family that is

endemic Endemism is the state of a species being found only 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 foun ...

Guadalupe Island Guadalupe Island () 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 various volcanoes are extinc ...

off the western coast of

Baja California Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of B ...

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

. 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. The species is common across much of temperate North America and in summer it ranges far into the Arctic. It is a 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 d ...

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 ''Hesperocyparis guadalupensis'', commonly known as Guadalupe cypress, is a species of western cypress from Guadalupe Island in the Pacific Ocean off the western coast of Mexico's Baja Peninsula. It was previously known as ''Cupressus guadalup ...

'') groves 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 (on Guadalupe Island and Cedros island). It is an evergreen conifer in t ...

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

habitat In ecology, habitat refers to the array of resources, 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 manifestation of its ...

for breeding. It ranged over the whole island for feeding then, and indeed still does theoretically, but actually only a handful of flocks exist, mostly in the northern part of the island. A testimony to the adaptability of this species 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 petioles (many other ''Nicotiana'' spec ...

'') 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 to 100 adult birds are thought to survive, mostly in the northern part of the island.

Domestic goat The goat or domestic goat (''Capra hircus'') is a species of goat-antelope that is mostly 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 family Bo ...

s (''Capra hircus'') that were introduced to the island to provide food for fishermen and to start a meat canning plant in the early to mid-19th century became feral, multiplied and overran it 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), that is, square metres (), and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. ...

(nearly two per

acre The acre ( ) is a Unit of measurement, unit of land area used in the Imperial units, British imperial and the United States customary units#Area, United States customary systems. It is traditionally defined as the area of one Chain (unit), ch ...

) being present around the 1870s.

Domestic cat The cat (''Felis catus''), also referred to as the domestic cat or house cat, is a small Domestication, domesticated carnivorous mammal. It is the only domesticated species of the family Felidae. Advances in archaeology and genetics have sh ...

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

feral goat The feral goat is the domestic goat (''Capra 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 domestic goats, all of which stem from the wild go ...

s, the endemic wildlife was destroyed by the feral cats. 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 the feral goats destroying the habitat and the 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 in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common List of feeding behaviours, feeding behaviours that includes parasitism and micropredation ...

s. The feral goats were

extirpated Local extinction, also extirpation, is the termination of a species (or other taxon) in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinctions. Local extinctions mark a chan ...

from the island by 2006 by the Grupo de Ecologia y Conservacion de Islas and Island Conservation, permitting a 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 containment (at the least) or extirpation (at the most) 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 an inventory of the global conservation status and extinction risk of biological ...

, 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, inv ...

Description and ecology

Decline to near-extinction

Footnotes

Further reading