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Draft Revised Recovery Plan for the Aga or Mariana Crow (Corvus kubaryi)

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Fish and Wildlife Service, Interior.


Notice of document availability for review and comment.


The U.S. Fish and Wildlife Service (“we”) announces the availability of the Draft Revised Recovery Plan for the Aga or Mariana Crow (Corvus kubaryi) for public review and comment.


Comments on the draft revised recovery plan must be received on or before March 13, 2006.


Copies of the draft revised recovery plan are available for inspection, by appointment, during normal business hours at the following location: U.S. Fish and Wildlife Service, Pacific Islands Fish and Wildlife Office, 300 Ala Moana Boulevard, Room 3-122, Box 50088, Honolulu, Hawaii 96850 (phone: 808-792-9400). Requests for copies of the draft revised recovery plan and written comments and materials regarding this plan should be addressed to the Field Supervisor, Ecological Services, at the above Honolulu address. The draft revised plan is currently available on the World Wide Web at​recovery/​index.html#plans.

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Fred Amidon, Fish and Wildlife Biologist, at the above Honolulu address and telephone number.

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Recovery of endangered or threatened animals and plants is a primary goal of the Endangered Species Act (Act) (16 U.S.C. 1531 et seq.) and our endangered species program. Recovery means improvement of the status of listed species to the point at which listing is no longer required under the criteria set out in section 4(a)(1) of the Act. Recovery plans describe actions considered necessary for the conservation of the species, establish criteria for downlisting or delisting listed species, and estimate time and cost for implementing the measures needed for recovery.

The Act requires the development of recovery plans for endangered or threatened species unless such a plan would not promote the conservation of Start Printed Page 1767the species. Section 4(f) of the Act requires that public notice, and an opportunity for public review and comment, be provided during recovery plan development. We will consider all information presented during the public comment period on each new or revised recovery plan. Substantive comments may result in changes to a recovery plan. Comments regarding recovery plan implementation may not necessarily result in changes to the recovery plans, but will be forwarded to the appropriate Federal agency or other entities so that they can take these comments into account during the course of implementing recovery actions. Individual responses to comments will not be provided.

The aga or Mariana crow is native to the islands of Guam and Rota in the Mariana Archipelago of the Pacific Ocean. The aga has been listed as an endangered species by the United States since 1984, and is also listed by the governments of the Territory of Guam and the Commonwealth of the Northern Mariana Islands. The last of the aga on Guam disappeared sometime in 2002 or 2003. Currently, northern Guam has a small population of 10 aga, all individuals translocated from Rota. Estimates for the island of Rota indicate that approximately 85 pairs of aga persist there, but this population is apparently in decline.

Aga utilize a wide variety of forested habitats including limestone, strand, ravine, agricultural forest, and secondary forests. However, available evidence suggests that aga are most abundant in native limestone forests. On both Guam and Rota, aga nests have been found exclusively in native species of trees, which also serve as the primary foraging sources for these birds.

The introduction of the exotic brown treesnake (Boiga irregularis) to the island of Guam in the late 1940's is believed to have been the primary cause of the extirpation of aga from that island. Brown treesnakes are not established on Rota. The cause of the observed decline in the aga population on Rota, as well as parallel declines in other forest birds on the island, is not well understood, but may be due to a combination of habitat loss, human persecution, and possibly introduced rats or other exotic predators.

Captive propagation of the aga in mainland zoos was attempted in the 1990's, but was largely unsuccessful. Most of the captive individuals have since been released back on Guam. The translocation of individuals from Rota to Guam has proven a more viable option, and in recent years some of these birds have paired and successfully nested on Guam. Since the native aga on Guam have been extirpated, recovery of the species is now entirely dependent upon the remaining population of aga on the island of Rota.

This draft revised recovery plan replaces the original recovery plan for the aga, which was published in 1990 and addressed multiple species of native forest birds of Guam and Rota. The draft revised recovery plan was developed by the Mariana Crow Recovery Team, which includes representatives from various Federal agencies, the Guam Division of Aquatic and Wildlife Resources, the Commonwealth of the Northern Mariana Islands' Division of Fish and Wildlife, Andersen Air Force Base, the University of Hawaii, and the University of Washington. The primary objective of this draft revised recovery plan is to establish a total of at least three viable, self-sustaining subpopulations of aga in the wild, two on Guam and one on Rota. The recovery program described in this draft revised recovery plan includes active research, habitat management, predator control, translocation, population monitoring, and community involvement. The recovery actions are designed to address threats to the aga in order to achieve the recovery goal of downlisting to threatened status and then eventually delisting (removing from the List of Endangered and Threatened Wildlife and Plants).

Public Comments Solicited

We solicit written comments on the draft revised recovery plan described. All comments received by the date specified above will be considered prior to approval of this plan.


The authority for this action is section 4(f) of the Endangered Species Act, 16 U.S.C. 1533(f).

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Dated: September 28, 2005.

David J. Wesley,

Acting Regional Director, Region 1, U.S. Fish and Wildlife Service.

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Editorial Note:

This document was received at the Office of the Federal Register on January 6, 2006.

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[FR Doc. E6-143 Filed 1-10-06; 8:45 am]