Migratory Bird Species in Young Tropical Forest Restoration Sites: Effects of Vegetation Height, Planting Design, and Season

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This study examines the difference in habitat preference of four migratory birds in restored forests in southern Costa Rica.

Research Goals & Methods

The restoration sites were 4-5 years old, planted with Terminalia amazonica, Vochysia guatemalensis, Erythrina poeppigiana, and Inga edulis. Initial plantings were conducted in restoration patches of 50m x 50m, planted either entirely (plantation style) or in small mini-patches (island technique). Birds in these areas were compared with control sites where there was no planting. Researchers used mist nets to monitor four Neotropical migrants: Chestnut-sided Warbler Dendroica pensylvanica, Mourning Warbler Oporornis philadelphia, Swainson’s Thrush Catharus ustulatus, and Tennessee Warbler Vermivora peregrina.

Conclusions & Takeaways

Chestnut-sided Warblers, Swainson’s Thrushes, and Tennessee Warblers were captured significantly more often in plantations than islands or controls. The Mourning Warbler was the only species for which vegetation height was a significant positive influence. This is likely because these four species are identified as species that use woody vegetation. Beyond the four target species, more birds were caught in the plantation (24) than in the islands (19) and in the control area (15). Authors conclude that although plantation-style restoration treatments are more expensive than islands, they may be more ecologically effective for Neotropical migratory birds.