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Dendroica kirtlandii
– Near Threatened
Taxonomy
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Kingdom:
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ANIMALIA
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Phylum:
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CHORDATA
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Class:
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AVES
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Order:
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PASSERIFORMES
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Family:
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PARULIDAE
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Scientific Name:
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Dendroica kirtlandii
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Species Authority:
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(Baird, 1852)
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Common Name/s:
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| English | — | KIRTLAND'S WARBLER |
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Assessment Information
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Red List Category & Criteria:
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NT ver 3.1 (2001)
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Year Assessed:
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2005
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Assessor/s:
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BirdLife International
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Evaluator/s:
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Butchart, S. & Wege, D. (BirdLife International Red List Authority)
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Justification:
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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. Its occupied breeding and wintering ranges are now considered large enough to warrant downlisting this species to Near Threatened. Almost qualifies for threatened under criteria D2.
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History:
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| 1988 | - | Threatened (Collar and Andrew 1988) |
| 1994 | - | Vulnerable (Collar, Crosby and Stattersfield 1994) |
| 2000 | - | Vulnerable (BirdLife International 2000) |
| 2004 | - | Vulnerable (BirdLife International 2004) |
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Geographic Range
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Range Description:
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Dendroica kirtlandii breeds in north and central Michigan, with small numbers (and occasional breeding) in Michigan's Upper Peninsula and Wisconsin, USA. Singing males have been recorded in Ontario and Quebec, Canada1,8,11,14. Breeding habitat has declined by 33% since the 1960s, but is more extensive than the 18 km² occupied in 19949. It has a very small winter range in the Bahamas and the Turks and Caicos Islands (to UK), either concentrated in the northern islands or spread throughout the Bahama Archipelago5,12. There were major declines in c.1900-1920 and 1961-19715, with the population just 167 singing males in 1974 and 19872. Numbers have recovered to 1,202 singing males in Michigan in 2003, the highest since surveys began in 19517.
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Range Map:
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 (click for detailed map)
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Countries:
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Native:
Bahamas; Mexico; Turks and Caicos Islands; United States
Vagrant:
Bermuda
Uncertain presence and origin:
Canada
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Population
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Population Trend:
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Habitat and Ecology
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Habitat and Ecology:
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Optimal breeding habitat is fire-maintained homogeneous stands of 2-4 m tall jack pines Pinus banksiana on sandy soil8,11. Eggs are laid in May-June3. Wintering habitat is either primarily Caribbean pine P. caribbaea5, or natural and secondary scrub, and saline/upland ecotone12.
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System:
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Terrestrial
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Threats
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Threats:
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If scrub is the preferred winter habitat, key threats are fire suppression and brood-parasitism by Brown-headed Cowbirds Molothrus ater in Michigan12. If Caribbean pine is preferred, habitat loss on the wintering ground is probably more important5. The latter is considered likely because of the failure to occupy all breeding habitat, and changes in population have occurred contemporaneously with the degradation and recovery of the north Bahamas pine ecosystem5. Recently however the four-fold 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 availability14. Consequentially, the current breeding range is too large for fire to affect the whole population rapidly.
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Conservation Actions
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Conservation Actions:
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Conservation measures underway:
CMS Appendix I. Management replicating the effects of natural fires has expanded potential breeding habitat to c.516 km2 10,11. Since 1972, a cowbird trapping programme has reduced parasitism from 70% to 3%2. Education and ecotourism initiatives in Michigan include an annual Kirtland's Warbler Festival10. Surveys have been undertaken in the Bahamas, most recently in 19984,5. There is a project in progress to establish the principal wintering habitat6.
Conservation measures proposed:
Ascertain winter habitat requirements. Continue existing initiatives - this will need $1 million per year to maintain13. Research the effects of management on breeding ecology11. Implement prescribed burning for all breeding habitat11. This is not possible in many areas, where it has been replaced by commercial clearouts, followed by a replant or reseed13. 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 program13. Investigate more economical cowbird control11.
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