Ecological indicators of restoration success: Fish community distribution, composition, and sampling strategies within the Picayune Strand Restoration Project

• Main Author: Young, Ryan C
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01-01-2013
• Subjects: Biology; Ecology; Environmental science
• ISBN: 9781303695469; 1303695464

Increasing awareness of the damage inflicted upon natural systems by human beings has brought ecological restoration to the forefront of environmental research efforts of the 21st century. Florida leads the country with some of the largest restoration projects in our nation's history. This study was designed to evaluate the success of restoration activities within the Picayune Strand Restoration Project, part of one of the world's largest restoration efforts the Comprehensive Everglades Restoration Plan. This study was conducted by collecting and analyzing data on fish community structure- species diversity and species abundance—in relation to various restoration phases. These restoration phases included two treatments (impacted unrestored areas, transitional recently restored areas), and reference wetlands (non-impacted natural wetland). Fish community data were collected monthly through the period of inundation with passive sampling using Breder traps as well as active dip net sampling. Based on the abundance and diversity data, results indicated that species richness, abundance, and diversity was lowest in impacted areas, increased in transitional recently restored areas, and was highest in both abundance and diversity in natural reference areas. Fish community data also indicated distinct groupings and similarities within each restoration phase and indicated varied species distribution among sites of different restoration phases. This analysis confirmed that fish community assemblages differed significantly among all three restoration treatments. Several indicator species were identified including Gambusia holbrooki, Jordonella floridae, and Fundulus confluentus which helped to drive the dissimilarity between different phases of restoration. In addition, the majority of species captured were only found in reference wetlands. These findings serve as an indicator that the restoration activities in the Picayune Stand are effective, and that several fish species may be used as indicators of hydrologic restoration success in ephemeral wetlands of Southwest Florida. Further analysis was conducted to observe patterns in sampling effort and temporal changes in community structure in order to determine the sampling frequency required to obtain a robust signal, the time of year most appropriate for collecting samples of a mature fish community, and patterns of dispersion over multivariate space through the period of inundation. Based on this one-year study, community data suggested that the months of October and November provided the best examples of a mature fish community and that sampling at a frequency of every third month (September, December, and March) provided sufficient community data to obtain a robust signal of change following restoration. These findings serve as indication that a sampling frequency of every third month is required to obtain the information necessary to make informed decisions about restoration activities, and that the optimal time period for sampling a mature fish community occurs during the months of October and November. This study provides evidence that the Picayune Strand Restoration Project is successfully restoring native fish populations.