dcsimg

Biology

provided by Arkive
Not only do the nectar, pollen and fruit of Opuntia cacti provide an important source of food for the Floreana mockingbird, but the branching pads commonly support this species' nests (5). Nonetheless, it does also spend considerable time foraging on the ground and in other types of vegetation for alternative sources of food, including insects, other fruits and berries, the eggs of iguanas and seabirds, and carrion (2) (7) (8) (9). The Floreana mockingbird is a cooperative breeder, with young birds helping adults to rear offspring before eventually breeding themselves (2) (3) (10). Although these territorial groups can range in size from 2 to 24 birds, usually they comprise only one or two pairs that actually breed (3).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Conservation

provided by Arkive
In 2008, the Charles Darwin Foundation, in collaboration with several other international organisations, set out an emergency management plan to preserve the imperilled Floreana mockingbird by reintroducing it to its original home on Floreana. This bold scheme is expected to be carried out in phases over a period of approximately ten years. The initial phase will involve eradicating all introduced species from Floreana and developing a program to breed mockingbirds in captivity. This will be followed by the first release trials of captive bred birds and finally the supervision and monitoring of the released population (11). It is hoped that the first mockingbirds will be returned to Floreana auspiciously during 2009, the bicentenary of the birth of Charles Darwin (11) (12).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Description

provided by Arkive
Three species of mockingbird, each occupying different islands in the Galapagos archipelago, had a greater early influence on Darwin's theory of Natural Selection than any other animal or plant (3). Darwin discovered the mockingbirds in 1835, whilst exploring the islands aboard the Beagle, but within 50 years of his visit, the once ubiquitous Floreana mockingbird had disappeared from the island of Floreana (2) (3) (4). Since then, this small, brown passerine has been clinging to survival on two small islets (2) (3) (5). Arguably less remarkable in appearance then it is in historical importance, the Floreana mockingbird has dark-brownish grey upperparts and dull white underparts, with distinct dark patches on the sides of its breast. Its eyes are reddish-brown and its beak is long and curved (2) (5).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Habitat

provided by Arkive
The Floreana mockingbird is often found amongst Opuntia cacti but also inhabits other stands of vegetation (2) (5) (6).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Range

provided by Arkive
Endemic to the Galapagos, the Floreana mockingbird is confined to the islets of Gardner-by-Floreana and Champion, adjacent to Floreana Island (2) (3) (5). It has the smallest available range of the four species of mockingbird occurring in the archipelago (3).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Status

provided by Arkive
Classified as Critically Endangered (CR) on the IUCN Red List (1).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Threats

provided by Arkive
With fewer than 150 individuals remaining (as of 2007), the Floreana mockingbird is one of the rarest and most threatened birds in the world (3) (11). Its original extinction from Floreana was probably a combination of several factors, including the introduction of black rats (Rattus rattus) and the loss of Opuntia habitat brought about by invasive herbivores (2) (3) (5). In contrast, the current population decline is thought to be being primarily driven by an increase in the frequency of dry La Niña years, which lead to high levels of adult mortality (2) (5) (11). The remaining population is likely to have lost a significant amount of genetic diversity, and, given its precariously small size, is in a severely vulnerable state (2). A single extreme weather event could easily decimate the entire surviving population, whilst the colonisation of the Floreana islets by a predatory bird, the smooth billed ani, presents additional concerns. This is not to mention the ever present spectre of an avian disease spreading to the mockingbird population, or the introduction of the black rat from neighbouring islets (2) (5).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Floreana mockingbird

provided by wikipedia EN

The Floreana mockingbird (Mimus trifasciatus) or the Charles Island mockingbird, is a species of bird in the family Mimidae. It was endemic to Floreana, one of the Galápagos Islands, but now is found only on two nearby islets, Campeón and Gardner-near-Floreana.[2][3][4] The Floreana mockingbird is also known as Darwin's mockingbird, as it was the arguable inspiration for Charles Darwin's work on the origins of species; he noticed distinct differences between them and previous species he had encountered and consequently established the existence of other variants on neighboring islands.[5]

Taxonomy and systematics

The Floreana mockingbird, Galapagos mockingbird (Mimus parvulus), Espanola mockingbird (M. macdonaldi), and San Cristobal mockingbird (M. melanotis) were previously placed in genus Nesomimus and were considered conspecific. They now form a superspecies. The Floreana mockingbird is monotypic.[2][3][4]

Description

The Floreana mockingbird is 25 to 26 cm (9.8 to 10.2 in) long. Males weigh an average of 65.7 g (2.32 oz) and females 59.8 g (2.11 oz). Adults have a pied appearance. They have a pale supercilium, a black patch in front of the eye, a darkish one below it, and white cheeks. Their crown, upperparts, and tail are grayish brown with a few faint darker streaks. Their whitish underparts have a dark patch on the side of the breast and faint spots on the breast and flanks. The folded wing shows two white bars. The juvenile is similar to the adult but more heavily streaked.[3]

Distribution and habitat

The Floreana mockingbird was formerly abundant on Floreana Island but had been extirpated from there by 1888. It now occurs only on two islets off Floreana's shore, Campeón and Gardner-near-Floreana. The islets provide a habitat of low vegetation along their shores and arid scrub with cacti and a few trees inland.[3]

Behavior

Feeding

The Floreana mockingbird mostly forages on the ground, but also in vegetation. It is primarily insectivorous but also eats cactus fruit, carrion, and probably seabird eggs.[3]

Breeding

The Floreana mockingbird's breeding season spans from October to April and two broods are usual. It is a cooperative breeder with up to five adults in each territory of about 2 ha (4.9 acres). The nest is a cup made of twigs lined with finer material; it is almost always placed in a cactus. The clutch size is two to four.[3]

Vocalization

The Floreana mockingbird has a "[l]oud, melodious song [and] does not mimic other species."[3]

Status

The IUCN in 1994 initially assessed the Floreana mockingbird as Endangered. In 2008 it was reclassified as Critically Endangered but then in 2017 returned to Endangered status. It was extirpated from Floreana by 1888; introduced rats, mice, cats, dogs, and goats have all been implicated as causes. The population on the two islets has fluctuated with the presence or absence of El Niño events but is believed to exceed 250 individuals and be stable.[1][3]

Repopulation efforts

Studies are under way to attempt to reintroduce the Floreana mockingbird to the main island. These include assessments of Floreana's habitat and the status of the introduced predators and competitors.[6][7]

References

  1. ^ a b BirdLife International (2018). "Floreana Mockingbird Melanotis trifasciatus". IUCN Red List of Threatened Species. 2018. Retrieved 24 July 2021.
  2. ^ a b Gill, F.; Donsker, D.; Rasmussen, P. (July 2021). "IOC World Bird List (v 11.2)". Retrieved July 14, 2021.
  3. ^ a b c d e f g h Cody, M. L. and C. J. Sharpe (2020). Floreana Mockingbird (Mimus trifasciatus), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.chamoc1.01 retrieved July 24, 2021
  4. ^ a b Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 23 May 2021. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved May 24, 2021
  5. ^ "Darwin's mockingbirds knock finches off perch".
  6. ^ Gill, Victoria (November 18, 2009). "DNA clue to save rare Darwin bird".
  7. ^ Gupta, Avani (2019). "Project update: Floreana mockingbird". Galapagos Conservation Trust. Retrieved July 24, 2021.
license
cc-by-sa-3.0
copyright
Wikipedia authors and editors
original
visit source
partner site
wikipedia EN

Floreana mockingbird: Brief Summary

provided by wikipedia EN

The Floreana mockingbird (Mimus trifasciatus) or the Charles Island mockingbird, is a species of bird in the family Mimidae. It was endemic to Floreana, one of the Galápagos Islands, but now is found only on two nearby islets, Campeón and Gardner-near-Floreana. The Floreana mockingbird is also known as Darwin's mockingbird, as it was the arguable inspiration for Charles Darwin's work on the origins of species; he noticed distinct differences between them and previous species he had encountered and consequently established the existence of other variants on neighboring islands.

license
cc-by-sa-3.0
copyright
Wikipedia authors and editors
original
visit source
partner site
wikipedia EN