Abstract Detail

Ecological Section

Bufford, Jennifer L [1], González, Eugenio [2].

Dominance and diversity: The effect of cattail (Typha domingensis) management on a tropical seasonally dry wetland.

Palo Verde National Park, Guanacaste, Costa Rica, is a RAMSAR Wetland of International Importance because it provides critical habitat for thousands of resident and migrating waterfowl and wading birds. Since the early 1980s, however, the park has been struggling to maintain bird habitat in the face of aggressive native cattail (Typha domingensis) expansion. This study examined the effect of cattail management, using a crushing technique called fangueo, on plant community dominance and diversity by comparing the area treated in January 2010 with two sites which had been treated several years ago, one of which is dominated by native Thalia geniculata and one of which is dominated by cattail. Transects were constructed through each site and percent cover of all plant species present was estimated in quadrats along each transect. Preliminary results show highest plant community diversity in the site dominated by Thalia geniculata (H’ = 2.14 ± 0.034) and lowest diversity in the cattail-dominated site (H’ = 1.02 ± 0.11). Individual quadrats dominated (>30% cover) by cattail also had lower diversity (H’ = 0.49 ± 0.06) than quadrats dominated by any other species. Bird use of the habitats present at each site was also surveyed and preliminary results suggest that most waterfowl avoid cattail-dominated patches and prefer recently treated areas for feeding and resting, while wading birds feed primarily in open water, but roost in patches of Thalia. These results support previous studies by documenting the effects of cattail on both plant and animal communities and by confirming the need for routine treatment in order to prevent cattail encroachment on critical bird habitat. The results suggest that fangueo should be repeated once every 2-3 years. This return interval allows plots to recover from the effects of fangueo, thus maximizing plant diversity and creating habitat heterogeneity, but is frequent enough to maintain open water for bird habitat and prevent the formation of dense cattail stands.

Broader Impacts:

1 - University of Hawaii, Botany Department, 3190 Maile Way, Honolulu, HI, 96822, USA
2 - Texas A&M University, Soltis Center for Research and Education, Apdo 80-4417 , Fortuna, San Carlos, Costa Rica

Keywords:
Typha
management
Wetland Plants
plant diversity
avian habitat use
Palo Verde, Costa Rica
Seasonal Dry Tropical Ecosystems.

Presentation Type: Oral Paper:Papers for Sections
Session: 21
Location: 552A/Convention Center
Date: Monday, August 2nd, 2010
Time: 4:15 PM
Number: 21003
Abstract ID:768