Invasive Species Biology: warring factions

1. Invasive Species Biology: warring factions James D. Ackerman Raymond Tremblay Paul Bayman & José Carlos Rodrigues

2. Floristic Globalization • Through a plethora of human activities, plant introductions have been occurring for centuries. • Some have become invasive, drastically altering the communities and ecosystems in which they have become established. • The effects of other plant naturalizations have been more subtle.

3. Plant Introductions • Some have become invasive, drastically altering the communities and ecosystems in which they have become established. Melaleuca quinquenervia in Florida

4. Hawaii’s naturalized orchids • The effects of other plant naturalizations have been either negligible or more subtle. • Are they invasive?

5. Puerto Rico • Some of the same exotic species in Hawaii are spreading in Puerto Rico • Where do they occur? • How fast are they spreading? • What are the constraints to the naturalization process? • Are there negative effects on the native flora?

6. Model System: Spathoglottis plicata • Rapidly expanding range • Terrestrial • Disturbed habitats, both natural and man-made • White & pink forms • Apparently self-polllinating

7. Where do Spathoglottis plicata occur? • Travel extensive road systems in Puerto Rico, obtain GPS data for every population encountered. • Use GIS techniques to characterize present and potential distribution of S. plicata

8. How fast is Spathoglottis plicata spreading? • Establish plots where S. plicata occurs, conduct longitudinal demographic study • Conduct periodic roadside transect surveys Raymond Tremblay & Jose Rodrigues

9. What are the constraints to naturalization? • Mycorrhizae characterization • Many associates or • Specialized on a common mycorrhizal fungus? Paul Bayman with Spathoglottis looking for mycorrhizal fungi Bayman’s students with orchid mycorrhizae cultures

10. What are the constraints to naturalization? Density dependent flower & fruit herbivory Isa Espinosa at Spathoglottis density study site

11. Spathoglottis plicata High fruit set • But insect damage to flowers, fruits and inflorescences can severely dampen reproductive success

12. Spathoglottis plicata • Ants: friends or enemies? Scale insects & ants

13. Spathoglottis plicata • Ants: friends or enemies? Ants vs beetles

14. Spathoglottis plicata • Weevil damage: loss of reproductive effort • Weevils are native specialists on orchid flowers Stethobaris polita

15. Are there negative effects on the native flora? • Is frequency of damage to Bletia patula related to the presence of weevil-infested S. plicata? • Is variation in the presence of the beetle related to reproductive success in B. patula? Almy Cuevas & Wilnelia Recart

16. CREST/CATECExpected Publication Outcomes • Spatial distribution and performance of native and invasive Ardisia (Myrsinaceae) species in Puerto Rico: the anatomy of an invasion -- Marcia Muñoz • The effectiveness of native and exotic pollinators in Melocactus intortus(Cactaceae)-- Camilo Fagua

17. CREST/CATECExpected Publication Outcomes • Is floral and fruit herbivory density dependent in naturalized populations of the orchid Spathoglottis plicata? -- Isamalish Espinosa • Are ants effective defenders of the naturalized orchid Spathoglottis plicata? -- Carlos Vega • Naturalized orchids support flower weevil populations: dire consequences for native orchids? -- Wilnelia Recart • Wind and rain does the trick: mechanics of autogamy in naturalized orchid Spathoglottis plicata -- Alvaro Bravo • March of the Spathoglottis: present population growth and expected patterns of migration -- Wilnelia Recart • Ephemeral mycorrhizal specificity in an invasive orchid -- Paul Bayman • Demography of a naturalized orchid: the emerging dominance of Spathoglottis plicata -- Wilfredo Falcon