Recent changes in plant species diversity in urban Pelham Bay Park, 1947-1998

Anthropogenic activity and natural successional processes negatively affected native plant species diversity in Pelham Bay Park, New York City. From 1947 to 1994, 25.5% of the native species were extirpated from this urban park, a rate of 2.9 species lost per year. Native species of the flora declined from 71.7% in 1947 to 59.6% in 1994-98. Native herbaceous species were significantly more likely to be extirpated than native woody species. Native species of meadow-type habitats were significantly more likely to be extirpated than species found in woodlands. By comparison, the number of non-native species found increased by 39.7% since 1947. Each of the different habitats in the park had a greater proportion of alien species in 1994-1998 than in 1946-1947. The key element in creating support for preserving the extant biodiversity of Pelham Bay Park is conservation education that stresses the importance of the city's biological heritage.