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1. Long-term management planning for conservation-reliant migratory songbirds is particularly challenging because habitat quality in different stages and geographic locations of the annual cycle can have direct and carry-over effects that influence the population dynamics. The Neotropical migratory songbird Kirtland's warbler Setophaga kirtlandii (Baird 1852) is listed as endangered under the U.S. Endangered Species Act and Near Threatened under the IUCN Red List. This conservation-reliant species is being considered for U.S. federal delisting because the species has surpassed the designated 1000 breeding pairs recovery threshold since 2001. 2. To help inform the delisting decision and long-term management efforts, we developed a population simulation model for the Kirtland's warbler that incorporated both breeding and wintering grounds habitat dynamics, and projected population viability based on current environmental conditions and potential future management scenarios. Future management scenarios included the continuation of current management conditions, reduced productivity and carrying capacity due to the changes in habitat suitability from the creation of experimental jack pine Pinus banksiana (Lamb.) plantations, and reduced productivity from alteration of the brown-headed cowbird Molothrus ater (Boddaert 1783) removal programme. 3. Linking wintering grounds precipitation to productivity improved the accuracy of the model for replicating past observed population dynamics. Our future simulations indicate that the Kirtland's warbler population is stable under two potential future management scenarios: (i) continuation of current management practices and (ii) spatially restricting cowbird removal to the core breeding area, assuming that cowbirds reduce productivity in the remaining patches by ≤41%. The additional future management scenarios we assessed resulted in population declines. 4. Synthesis and applications. Our study indicates that the Kirtland's warbler population is stable under current management conditions and that the jack pine plantation and cowbird removal programmes continue to be necessary for the long-term persistence of the species. This study represents one of the first attempts to incorporate full annual cycle dynamics into a population viability analysis for a migratory bird, and our results indicate that incorporating wintering grounds dynamics improved the model performance.

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The threatened Kirtland's warbler Dendroica 25 pairs and at least nine nests fledged young. One male ringed as a fledgling returned to breed in two subsequent kirtlandii breeds in stands of young jack pine Pinus banksiana growing on well-drained soils in Michigan, years. After a 19-year period of population stability, the Kirtland's warbler population increased four-fold during USA. We summarize information documenting the range expansion of Kirtland's warbler due to increased habitat 1990-2000, most likely in response to a tripling in habitat area. This increase in sightings and documented breed-management in the core breeding range in the Lower Peninsula of Michigan during 1990-2000. We collected ing may be related to habitat availability in Michigan's Upper Peninsula and to saturation of habitat in the main records and conducted searches for the species in Michigan's Upper Peninsula and Wisconsin over 1978-breeding range. The increase in extra-limital records during 1995-1999 corresponds to the time when the 2000. During that time 25 males were found in Wisconsin and 90 males in the Upper Peninsula. We documented population went from the minimum to the maximum projected population densities, and a decline in natural colonization of Michigan's Upper Peninsula by six ringed males from the Lower Peninsula of Michigan. Four ringed wildfire habitat was just oCset by new managed habitat for the Kirtland's warbler. birds also moved back to the core breeding range, including two males that made two-way movements between the core breeding range and the Upper Peninsula. Thirty-Keywords Carrying capacity, colonization, dispersal, Dendroica kirtlandii, jack pine, Michigan, population seven females were observed with males from 1995 to 2000, all in Michigan. Nesting activities were noted for expansion, Wisconsin, USA.