Foothills olive tyrant

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Foothills olive tyrant
Myiopagis olallai coopmansi

Myiopagis olallai coopmansi

Systematics
Subordination : Screeching Birds (Tyranni)
Family : Tyrants (Tyrannidae)
Subfamily : Olivtyrannen (Elaeniinae)
Tribe : Elaeniini
Genre : Myiopagis
Type : Foothills olive tyrant
Scientific name
Myiopagis olallai
Coopmans & Krabbe , 2000

The foothills olive tyrant ( Myiopagis olallai ) is a screech bird from the family of tyrants (Tyrannidae). It occurs in three subspecies in Ecuador , Colombia , Peru and Venezuela . The art epithet honors the Ecuadorian-Brazilian animal collector Alfonso Maria Olalla (1899–1971).

Discovery story

In 1991, the Belgian ornithologist Paul Coopmans first heard the vocalizations of a type of tyrant that he could not identify. In 1992 he made a tape recording of this kind at an altitude of 1000 m near Zamora in southern Ecuador. After comparing it with the vocalizations of other types of tyrant, Coopmans was convinced that he had discovered a new species. In 1994 the first two specimens were collected on the Río Bombuscaro in the province of Zamora Chinchipe . In 1996 two more specimens were added, which were collected at the Sumaco volcano in the Napo province in north-central Ecuador. These four bellows were used by Coopmans and his colleague Niels Krabbe in 2000 as type specimens for the first scientific description as Myiopagis olallai .

features

The foothill olive tyrant reaches a body length of 12 to 12.5 cm and a weight of 11 to 14 g. He has a dark pearl gray skull with a half-hidden, large, white vertex. The reins and the ear covers are mottled gray and white. The iris is dark brown. The eye ring and the area under the eyes as well as the top are washed out olive green. The wings are dark brown with three conspicuous, light sulfur yellow wing bands. The umbrella feathers, the arm wings and the outer flags of the inner control feathers have sulfur-yellow hems. The tail is gray-brown. The over-eye stripe is light and the eye stripe is dark. The throat is whitish. The underside is light yellow with broad, olive-green dots on the chest. The short beak is black with a gray base on the lower jaw. The legs are black. The sexes look the same, the juvenile birds are undescribed.

Subspecies and their distribution

The nominate form Myiopagis olallai olallai occurs in the east in the north and south of Ecuador, in south-central Peru and in southern Colombia. The subspecies Myiopagis olallai coopmansi is found in the Cordillera Central of Colombia. The subspecies Myiopagis olallai incognita is restricted to the Sierra de Perijá in Venezuela.

Vocalizations

The vocalizations consist of long, hard trills that rise significantly in pitch and last about 2 seconds, followed by a variable number of introductory tones that also vary in tempo and rhythm. There are also fast, descending trilling “t'eerr” tones.

habitat

The foothill olive tyrant occurs in and on the edges of very moist to humid foothill primary forests , at altitudes of 890 to 1500 m.

Eating behavior

While foraging for food, the foothill olive tyrant sits horizontally, often with a cocked tail. They are generally very active, making short upward or outward pecking flights and short soaring flights to search the top and bottom of leaves, moss, twigs and branches for prey. The subspecies Myiopagis olallai coopmansi can be found in mixed swarms in the canopy . The stomach contents examined consisted of 6 mm long black beetles, caterpillars, insect larvae, hymenoptera and spiders. Berries are probably also part of the food supply. The foothill olive tyrant calls and sings frequently while standing vertically on a perch at the tip of a branch 2 to 15 m above the ground.

Reproductive behavior

The reproductive behavior has not been researched.

status

The IUCN lists the promontory-Olivtyrann into the category of "endangered" ( vulnerable ). In some places on the eastern slopes of the Andes, the habitat is being destroyed at an alarming rate. Complete deforestation and less intensive habitat destruction and fragmentation may have resulted in the loss of around half of the foothill forest area in the species' range in Ecuador, where the rate of deforestation has increased since 2001. In addition, development projects that have already been approved are likely to further increase the future rate of forest loss in Ecuador.

literature

  • Paul Coopmans, Niels Krabbe: A new species of flycatcher (Tyrannidae: Myiopagis) from eastern Ecuador and eastern Peru. The Wilson Bulletin 112 (3), 2000, pp. 305-312
  • Andrés M. Cuervo. F. Gary Stiles , Miguel Lentino, Robb T. Brumfield , Elizabeth T. Derryberry: Geographic variation and phylogenetic relationships of Myiopagis olallai (Aves: Passeriformes; Tyrannidae), with the description of two new taxa from the Northern Andes. Zootaxa 3873 (1), 2014, pp. 1-24
  • David Brewer: Birds new to Science. Fifty Years of Avian Discoveries , Christopher Helm, London, 2018. ISBN 978-1-4729-0628-1 . Pp. 138-139
  • John W. Fitzpatrick : Foothill Elaenia (Myiopagis olallai) . In: J. del Hoyo, A. Elliott, J. Sargatal, DA Christie, E. de Juana (Eds.) Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona, ​​2019, accessed February 2, 2019.

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