YEAR-ROUND BIRD USE OF MONOTYPIC STANDS OF THE CHINESE TALLOW TREE, TRIADICA SEBIFERA, IN SOUTHEAST TEXAS

Invasive species pose the second greatest threat to biodiversity after habitat loss. Although invasive plant species negatively affect invaded ecosystems and diminish native biodiversity, they may provide food and other resources for some native birds. As monotypic stands of the invasive Chinese tallow tree (Triadica sebifera) become more common in the southeastern United States, it is important to assess their suitability as habitat for native forest birds. We used point counts to compare habitat use of forest birds in stands of native mixed-species forest, of mature tallow trees, and of young tallow trees on the coast of Texas during 2009 and 2010. The composition of trees in stands of mature and young tallow was more homogeneous than in stands of mixed native species, but mature tallow stands had an understory more complex than that of other habitat types. Mature tallow stands supported significantly fewer species of forest birds than did native forest only during the spring, and birds' population densities were similar in mature tallow and native forest throughout the year. Young tallow stands supported significantly fewer species of forest birds than did native forest in all seasons except for fall and significantly lower population densities during the breeding season (spring and summer). While monotypic stands of Chinese tallow trees provide suitable habitat for some forest birds, especially in winter, to preserve the widest diversity of forest birds we recommend the preservation of native mixed-species forest.