Guam kingfisher
Conservation status
Extinct in the Wild  (IUCN 3.1)[1]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Coraciiformes
Family:	Alcedinidae
Subfamily:	Halcyoninae
Genus:	Todiramphus
Species:	T. cinnamominus
Binomial name
Todiramphus cinnamominus (Swainson, 1821)

The Guam kingfisher (Todiramphus cinnamominus), called sihek in Chamorro,^[2] is a species of kingfisher from the United States Territory of Guam. It is restricted to a captive breeding program following its extinction in the wild due primarily to predation by the introduced brown tree snake.

In the indigenous Chamorro language, it is referred to as sihek.^[3]

The mysterious extinct Ryūkyū kingfisher, known from a single specimen, is sometimes placed as a subspecies (T. c. miyakoensis; Fry et al. 1992), but was declared invalid by the International Ornithological Congress in 2022, rendering the species monotypic.^[4] Among-island differences in morphological, behavioral, and ecological characteristics have been determined sufficient that Micronesian kingfisher populations, of which the Guam kingfisher was considered a subspecies, should be split into separate species.^[5]

This is a brilliantly colored, medium-sized kingfisher, 20–24 cm (7.9–9.4 in) in length. They have iridescent blue backs and rusty-cinnamon heads. Adult male Guam kingfishers have cinnamon underparts while females and juveniles are white below. They have large laterally-flattened bills and dark legs. The calls of Micronesian kingfishers are generally raspy chattering.^[6]

Guam kingfishers were terrestrial forest generalists that tended to be somewhat secretive. The birds nested in cavities excavated from soft-wooded trees and arboreal termitaria, on Guam.^[7] Micronesian kingfishers defended permanent territories as breeding pairs and family groups.^[8] Both sexes care for young, and some offspring remain with parents for extended periods. Research suggests that thermal environment has the potential to influence reproduction.^[8]

In the wild, the Guam kingfisher feeds on Insects, Spiders, Lizards, and small crustaceans. The birds dive and capture their prey on the ground, similar to other species of kingfishers that dive for fish in water.^[9]

The Guam kingfisher population was extirpated from its native habitat after the introduction of brown tree snakes.^[10] It was last seen in the wild in 1986, and the birds are now U.S. listed as endangered.^[6] The Guam kingfisher persists as a captive population of fewer than two hundred individuals (as of 2017) in US mainland and Guam breeding facilities. There are plans to reintroduce the Guam birds to Palmyra Atoll, and potentially also back to their native range on Guam if protected areas can be established and the threat of the brown tree snakes is eliminated or better controlled.^[3][6]

As of September 2024, all nine of the Guam kingfishers that have been transferred from the Brookfield Zoo, Cincinnati Zoo and Botanical Garden, National Aviary, Sedgwick County Zoo, and Disney's Animal Kingdom, have been released on Cooper Island, in Palmyra Atoll.^[11][12]

In 2023 the Guam kingfisher was featured on a United States Postal Service Forever stamp as part of the Endangered Species set, based on a photograph from Joel Sartore's Photo Ark. The stamp was dedicated at a ceremony at the National Grasslands Visitor Center in Wall, South Dakota.^[13]

A mated pair of Guam kingfishers can be viewed by the public at the National Aviary in Pittsburgh, one of the participants in the species survival plan.^[14]

• List of birds of Guam

• Laws, Rebecca J.; Kesler, Dylan C. (2012). "A Bayesian network approach for selecting translocation sites for endangered island birds". Biological Conservation. 155: 178–185. Bibcode:2012BCons.155..178L. doi:10.1016/j.biocon.2012.05.016.
• Kesler, Dylan C.; Haig, Susan M. (2007). "Conservation biology for suites of species: Demographic modeling for Pacific island kingfishers". Biological Conservation. 136 (4): 520–530. Bibcode:2007BCons.136..520K. doi:10.1016/j.biocon.2006.12.023. S2CID 52254797.
• Kesler, Dylan C.; Haig, Susan M. (2007). "Multiscale Habitat Use and Selection in Cooperatively Breeding Micronesian Kingfishers". The Journal of Wildlife Management. 71 (3): 765–772. Bibcode:2007JWMan..71..765K. doi:10.2193/2006-011. JSTOR 4495250. S2CID 4104260.
• Kesler, Dylan C.; Haig, Susan M. (2007). "Territoriality, Prospecting, and Dispersal in Cooperatively Breeding Micronesian Kingfishers (Todiramphus Cinnamominus Reichenbachii)". The Auk. 124 (2): 381. doi:10.1642/0004-8038(2007)124[381:TPADIC]2.0.CO;2. ISSN 0004-8038. S2CID 14032686.
• Kesler, Dylan C.; Haig, Susan M. (2005). "Microclimate and Nest-Site Selection in Micronesian Kingfishers". Pacific Science. 59 (4): 499–508. doi:10.1353/psc.2005.0045. hdl:10125/24196. S2CID 55536252.
• Kesler, D. (2005). Population demography, resource use, and movement in cooperatively breeding Micronesian Kingfishers (Thesis). S2CID 82407115.
• Kesler, Dylan C.; Haig, Susan M. (2004). "Thermal characteristics of wild and captive Micronesian kingfisher nesting habitats". Zoo Biology. 23 (4): 301–308. doi:10.1002/zoo.20010.
• Fry, C. Hilary; Fry, Kathie; Harris, Alan (1992). Kingfishers, Bee-eaters, and Rollers. Princeton, NJ: Princeton University Press. ISBN 978-0713680287.
• Haig, Susan M.; Ballou, Jonathan D. (1995). "Genetic Diversity in Two Avian Species Formerly Endemic to Guam". The Auk. 112 (2): 445–455. doi:10.2307/4088732. JSTOR 4088732.
• Haig, S. M.; Ballou, J. D.; Casna, N. J. (1995). "Genetic Identification of Kin in Micronesian Kingfishers". Journal of Heredity. 86 (6): 423–431. doi:10.1093/oxfordjournals.jhered.a111616.
• Marshall, Samuel D. (1989). "Nest Sites of the Micronesian Kingfisher on Guam". The Wilson Bulletin. 101 (3): 472–477. JSTOR 4162756.
• Pratt, H.D., P.L. Bruner, and D.G. Berrett. 1987. The Birds of Hawaii and the Tropical Pacific. Princeton University Press. Princeton, NJ.
• Savidge, Julie A. (1987). "Extinction of an Island Forest Avifauna by an Introduced Snake". Ecology. 68 (3): 660–668. Bibcode:1987Ecol...68..660S. doi:10.2307/1938471. JSTOR 1938471.
• U.S. Fish and Wildlife Service, 2004. Draft Revised Recovery Plan for the Sihek or Guam Micronesian Kingfisher (Halcyon cinnamomina cinnamomina).
• U.S. Fish and Wildlife Service, 1984. Endangered and threatened wildlife and plants: determination of endangered status for seven birds and two bats on Guam and the Northern Mariana Islands. Federal Register 50 CFR Part 17 49(167), 33881–33885.
• U.S. Fish and Wildlife Service, 2004. Draft Revised Recovery Plan for the Sihek or Guam Micronesian Kingfisher (Halcyon cinnamomina cinnamomina). U.S. Fish and Wildlife Service, Portland, OR.

• BirdLife Species Factsheet.
• Micronesian kingfisher Naturalis The Netherlands
• Philadelphia Zoo – Description of Guam Micronesian kingfisher Conservation efforts
• United States Fish and Wildlife Service Archived 9 December 2006 at the Wayback Machine – Threatened and Endangered Animals in the Pacific Islands.
• US Geological Survey – USGS Micronesian Avifauna Conservation Projects
• US Geological Survey – The Brown Treesnake on Guam.