Tinian Monarch

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Tinian Monarch

Monarcha takatsukasae

StatusThreatened
ListedJune 2, 1970
FamilyMuscicapidae (Old World Flycatcher)
DescriptionSmall songbird measuring 6 in (15 cm) in length with light underparts, olive-brown upper parts, dark-brown wings and white rump.
HabitatForests of second growth to well-developed native forests of Tinian in the Mariana Archipelago.
FoodInsects and plants.
ReproductionUnknown
ThreatsLoss of habitat and predation by the brown tree snake.
RangeMariana Islands

Description

The Tinian Monarch, Monarcha takatsukasae, is a small songbird measuring 6 in (15 cm) in length with light rufous underparts, olive-brown upper-parts, dark brown wings and tail, and white rump and undertail coverts.

Behavior

M. takatsukasae is insectivorous but also feeds on various plant life. Flycatchers, in general, feed by hovering and gleaning and/or hawking. They perch and wait for flying prey to come within range, fly out and capture the prey in mid-air.

The species is active during the day with possible peaks in activity occurring in the early morning and evening.

Habitat

The species is endemic to the island of Tinian in the Mariana Archipelago in the Western Pacific. It inhabited a variety of forest types ranging from introduced second growth to well-developed native forests. The habitat has changed to shrubby legume (Leucaena leucocephala ) due to deforestation by the Japanese for sugarcane production and the destruction of the remaining forest by military action during the Second World War. The Leucaena scrub habitat now makes up more than 70% of the land area on Tinian and is the only habitat utilized by this bird.

Distribution

The past and present distribution of this species is on the island of Tinian in the Mariana Archipelago in the Western Pacific Ocean. The species is limited by the small size of its island habitat (39 sq mi [101 sq km]). Natural populations are found nowhere else on Earth. In the event of rapid population decline, there is no gene pool reserve. In 1987 the population was estimated at 40,000 and it was considered to be stable.

Threats

Though its numbers have greatly rebounded since its listing as endangered in 1970, the species is designated as threatened due to the potential loss of its habitat. An exotic psyllid insect (Heteropsylla sp.) has invaded many of the Mariana Islands including Tinian. These insect-infested areas have caused the near-total defoliation of the Leucaena scrub habitat. This habitat makes up more than 70% of the land area on Tinian and is the only habitat utilized by this bird. The long-term impacts of this insect are unknown.

Another species, the brown tree snake, may threaten M. takatsukasae. The snake was introduced by the U.S. Military to Guam; all native forest birds have been disappearing over the last 20 years. The Military is trying to control the snake.

Conservation and Recovery

This species' population status has been listed as stable. The U.S. Fish and Wildlife Service has given M. takatsukasae a recovery priority rating of "14" which means that the degree of threat to the species is low and the recovery potential is high. The continued efforts for the recovery of this species include: (1) Brown tree snake removal and control; (2) Habitat restoration; and (3) Studies to determine the impact of vegetative defoliation by the psyllid insect, Heteropsylla sp. on M. takatsukasae.

Contact

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Building
911 N. E. 11th Ave.
Portland, Oregon 97232-4181
Telephone: (503) 231-6121
http://pacific.fws.gov/

Reference

U. S. Fish and Wildlife Service. 22 February 1999. "Endangered and Threatened Wildlife and Plants; Proposed Rule To Remove the Tinian Monarch From the Federal List of Endangered and Threatened Wildlife." Federal Register 64(34): 8533-8538.