Species

Justification
Since 1987, conservation action has successfully increased the population of this species. Numbers exceeded 500 singing males in 1994 following doubling of suitably aged habitat between 1987 and 1990. Numbers continue to increase, but its population and range remain small, hence its classification as Near Threatened.

Taxonomic source(s)
AOU. 1998. Check-list of North American birds. American Ornithologists' Union, Washington, D.C.
Sibley, C. G.; Monroe, B. L. 1990. Distribution and taxonomy of birds of the world. Yale University Press, New Haven, USA.
Stotz, D. F.; Fitzpatrick, J. W.; Parker, T. A.; Moskovits, D. K. 1996. Neotropical birds: ecology and conservation. University of Chicago Press, Chicago.

Identification
14.5 cm. Large grey-and-yellow warbler. Male, blue-grey above with diffuse black streaking on the mantle. Black lores and split white eye-ring. Yellow underparts with black streaking on flanks. Female, similar but paler with brown tinge to mantle and lacks black lores. Immature has greyish streaking and spots on throat. Voice Song an emphatic chip-chip-che-way-o.

Distribution and population
Almost the entire population of Dendroica kirtlandii breeds in north and central Michigan (Anon. 2008), with small numbers (and occasional breeding) in Michigan's Upper Peninsula and Wisconsin, U.S.A. Breeding was also recorded in Canada in 2007 for the first time since 1945 (Eskelsen 2007). Breeding habitat has declined by 33% since the 1960s, but is more extensive than the 18 km² occupied in 1994 (Nelson and Buech 1996). It has a very small winter range in the Bahamas and the Turks and Caicos Islands (to U.K.), either concentrated in the northern islands or spread throughout the Bahama Archipelago (Haney et al. 1998, Sykes and Clench 1998). There were major declines in c.1900-1920 and 1961-1971 (Haney et al. 1998), with the population numbering just 167 singing males in 1974 and 1987 (Anon. 1996). Numbers have recovered to 1,697 singing males in Michigan in 2007 (Line 2008), the highest since surveys began in 1951 (http://www.michigan.gov/dnr/0,1607,7-153--72725--,00.html, National Wildlife Refuge Association in litt. 2006).

Population justification
The population size continues to increase, with latest estimates putting it around 3,500 individuals, roughly equivalent to 2,300-2,400 mature individuals.

Trend justification
Following major declines in c.1900-1920 and 1961-19715, numbers have recovered from 167 singing males in 1974 to 1,478 singing males in Michigan in 2006, the highest since surveys began in 1951 (Wunderle et al. 2006).

Ecology
Its optimal breeding habitat is fire-maintained homogeneous stands of 1-5 m tall jack pines Pinus banksiana on sandy soil (Mayfield 1992, Sykes 1997, Anon. 2008). Eggs are laid in May and June (Curson et al. 1994). It winters in early-successional disturbed habitat (Wunderle et al. 2010), either stands of Caribbean pine P. caribbaea (Haney et al. 1998), or natural and secondary scrub, and saline/upland ecotone (Sykes and Clench 1998). It feeds on arthropods and abundant fruit during this time (Wunderle et al. 2010). Birds move from patch to patch in the wintering grounds as food supplies are depleted and areas dry out, eventually concentrating in small patches where they maintain small and overlapping home ranges (Wunderle et al. 2006).

Threats
If scrub is the preferred winter habitat, key threats are fire suppression and brood-parasitism by Brown-headed Cowbirds Molothrus ater in Michigan (Sykes and Clench 1998). If Caribbean pine is preferred, habitat loss on the wintering ground is probably more important. The latter is considered likely because of the species's failure to occupy all breeding habitat, and changes in population have occurred contemporaneously with the degradation and recovery of the north Bahamas pine ecosystem (Haney et al. 1998). Recently however the fourfold population increase between 1990 and 2000, coincident with a tripling of the available habitat through management, would appear to indicate that currently population levels are closely linked to habitat availability (Probst et al. 2003). Consequentially, the current breeding range is too large for fire to affect the whole population rapidly.

Conservation actions underway
CMS Appendix I. Management replicating the effects of natural fires has expanded potential breeding habitat to c.516 km² (Richter 1996, Sykes 1997). Since 1972, a cowbird trapping programme has reduced parasitism from 70% to 3% (Anon. 1996). Education and ecotourism initiatives in Michigan include an annual Kirtland's Warbler Festival (Richter 1996). Surveys have been undertaken in the Bahamas, most recently in 1998 (Haney et al. 1998, D. Ewert in litt. 1999). There is a project in progress to establish the principal wintering habitat (G. Hilton in litt. 2000). Virtually the entire population breeds within the 140,000-acre Kirtland's Warbler Management Area which includes the Huron National Forest, the Kirtland's Warbler National Wildlife Refuge and various Michigan state forests.

Conservation actions proposed
Maintain periodically-disturbed suitable habitat on its wintering grounds in the Bahamian archipelago (Wunderle et al. 2010). Continue existing initiatives, which will require $1 million per year (R. Rustem in litt. 2003). Study the effects of management on breeding ecology). Implement prescribed burning for all breeding habitat (Sykes 1997). This is not possible in many areas, where it has been replaced by commercial clearouts, followed by a replant or re-seed (R. Rustem in litt. 2003). Increase the area of jack pine - this is difficult to maintain due to the cost, and its future is uncertain because of the loss of the carbon sequestration program (R. Rustem in litt. 2003). Investigate more economical cowbird control (Sykes 1997).

Related state of the world's birds case studies

• Intensive habitat management has led to a spectacular increase in Kirtland's Warbler

References
Anon. 2008. Seeing Kirtland's Warbler in Michigan. Birding World 21(5): 211-213.

Collar, N. J.; Gonzaga, L. P.; Krabbe, N.; Madroño Nieto, A.; Naranjo, L. G.; Parker, T. A.; Wege, D. C. 1992. Threatened birds of the Americas: the ICBP/IUCN Red Data Book. International Council for Bird Preservation, Cambridge, U.K.

Mayfield, H. F. 1992. Kirtland's Warbler (Dendroica kirtlandi). In: Poole, A.; Gill, F. (ed.), The birds of North America, No. 19, pp. 1-16. The Academy of Natural Sciences, Philadelphia and The American Ornithologists' Union, Philadelphia and Washington, DC.

Richter, J. 1996. New friends for the Kirtland's Warbler. Endangered Species Bulletin 11: 12.

Curson, J.; Quinn, D.; Beadle, D. 1994. New World warblers. A&C Black/Christopher Helm, London.

Austen, M. J. W.; Cadman, M. D.; James, R. D. 1994. Ontario birds at risk. Federation of Ontario Naturalists and Long Point Bird Observatory, Ontario.

Anon. 1996. Forest fire helps Kirtland's Warbler. Canadian Wildlife: 43.

Nelson, M. D.; Buech, R. R. 1996. A test of three models of Kirtland's Warbler habitat suitability. Wildlife Society Bulletin 24: 89-97.

Sykes, P. W. 1997. A closer look: Kirtland's Warbler. Birding 29: 220-227.

Haney, J. C.; Lee, D. S.; Walsh-McGehee, M. 1998. A quantitative analysis of winter distribution and habitats of Kirtland's Warblers in the Bahamas. Condor 100: 201-217.

Sykes, P. W.; Clench, M. H. 1998. Winter habitat of Kirtland's Warbler: an endangered Neartic/Neotropical migrant. Wilson Bulletin 110: 244-261.

Line, L. 2008. Bouncing back [Kirtland's Warblers]. Audubon 110(2): 28.

Probst, J. R.; Donner, D. M.; Bocetti, C. I.; Sjogren, S. 2003. Population increase in Kirtland's warbler and summer range expansion to Wisconsin and Michigan's Upper Peninsula, USA. Oryx 37: 365-373.

Wunderle, J. M.; Currie, D.; Ewert, D. N. 2006. The response of wintering Kirtland's Warblers to food patch dynamics as the dry season proceeds in the Bahamas. Wings without borders: IV North American Ornithological Conference, October 3-7, 2006, Veracruz, Mexico, pp. 366. American Ornithologists' Union, Waco, TX, USA.

Eskelsen, J. 2007. Kirtland's Warblers found nesting outside Michigan. Birder's World 21(5): 14-16.

Wunderle, J. M., Jr.; Currie, D.; Helmer, E. H.; Ewert, D. N.; White, J. D.; Ruzycki, T. S.; Parresol, B.; Kwit, C. 2010. Kirtland's Warblers in anthropogenically disturbed early-successional habitats on Eleuthera, The Bahamas. Condor 112(1): 123-137.

Further web sources of information
Hear sounds for this species from xeno-canto, the community database of shared bird sounds from around the world.

View photos and videos, and hear sounds of this species from the Internet Bird Collection

Text account compilers
Benstead, P., Bird, J., Harding, M., Khwaja, N., Pople, R.

Contributors
Ewert, D., Hilton, G., Rustem, R.

IUCN Red List evaluators
Butchart, S., Symes, A.

Recommended citation
BirdLife International (2013) Species factsheet: Dendroica kirtlandii. Downloaded from http://www.birdlife.org on 21/05/2013. Recommended citation for factsheets for more than one species: BirdLife International (2013) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 21/05/2013.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.

Additional resources for this species

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