Non-Indigenous Fishes in Restored and Natural Wetlands on the Big Cypress Seminole Indian Reservation

Kristine J. Dunker and John C. Volin

Florida Atlantic University, Davie, FL

William Loftus

U. S. Geological Survey, Center for Water and Restoration Studies, Miami, FL

Establishment of non-native fishes in South Florida has been shown to adversely affect native fish communities, and an important goal of Everglades restoration is to minimize such impacts. Most studies on non-native fishes have taken place in Everglades National Park and the coastal canal system, while the effects of non-native fishes in the aquatic ecosystems of greater South Florida have been largely unexplored. In particular, the Big Cypress portion of the Greater Everglades Ecosystem has been poorly studied. Since fish are the primary basis of the food web that supports the bulk of the wading bird populations throughout southern Florida, as well as various mammalian and reptilian predators, this information is particularly important to successful restoration. In this study on the Big Cypress Seminole Indian Reservation (Figure 1) we are examining the development of new fish assemblages within a newly restored wetland and comparing these to nearby, less-impacted wetlands.

Figure 1. Location of the Big Cypress Seminole Indian Reservation in South Florida.

The Seminole Tribe of Florida has undertaken several wetland restoration projects on the Big Cypress Reservation. These include wetlands being restored in association with the USDA-NRCS as part of the Wetland Reserve Program (WRP) as well as wetland impoundments being created in the context of the Water Conservation Plan, a designated Critical Project of the Comprehensive Everglades Restoration Plan. In all these restoration projects, rehydration of the impoundments will be accomplished by pumping water in from adjacent canals. We have been comparing native and non-native fish community patterns in a WRP site, which is dominated by a formerly desiccated mixed forested wetland and pasture matrix, with historically similar but less impacted habitats. Our objective was to determine the response of both native and non-native fish populations to wetland restoration.

Data collection for this study began in May of 2001 and will continue through March, 2003. Sampling is being conducted in three habitat types; wet prairies, cypress swamps and canals using a variety of sampling methods. These methods include minnow traps, throw traps, gill nets, seines and boat electroshockers. We are also sampling in borrow ponds created during the construction of the WRP site because they are the main dry season refugia for fish and other aquatic organisms within the WRP. One concern with the WRP rehydration method is that non-native fish living in the canals may be introduced into the WRP impoundments. To partially address this, a net has been placed over the outflow of the WRP pump to attempt to block non-native fish introductions into the WRP. The net is regularly sampled to assess the effectiveness of this method in preventing fishes from entering.

A large number of fish species have been identified in both the restored wetland and in the less impacted natural habitat (Table 1). In the restored wetland, preliminary results collected through December 2002 show that both native and non-native fish species richness were highest in the adjacent canal and secondarily in the wet prairies/former pastures areas. The cypress swamps had the lowest overall native and non-native species richness. Sampling data for the same period collected in the natural area show that the canal had the highest overall species richness, but surprisingly, non-native species richness was highest in the cypress swamps. Data from the first wet season shows that native species diversity was higher in the natural area compared to the restored WRP site. However, non-native species diversities were not significantly different between the two sites. Interestingly, two non-native fish species not previously known to be present in the Big Cypress region were also documented, the brown hoplo (Hoplosternum littorale) and the pike killifish (Belonesox belizanus).

This study is establishing baseline data for fish communities in the Big Cypress region and is documenting the patterns of colonization and abundance of non-native fishes in a restored wetland in comparison with more natural habitats. We are also testing the effectiveness of blocking inflows for reducing colonization of a restored habitat by non-native fishes. These results may be useful to both land managers and scientists trying to limit non-native species introductions in wetland restoration sites.

Table 1. Native and non-native fish occurrence in habitats within the restored wetland and the

Native Area from March 2001 through December 2002.

Restored Wetland / Native Area
Family
Species / Wet
Prairies / Cypress Swamps / Canal / Wet Prairies / Cypress Swamps / Canal
Lepisosteidae
Lepisosteus platyrhincus / + / + / + / +
Cyprinidae
Notemigonus crysoleucas / + / + / +
Catostomidae
Erimyzon sucetta / +
Ictaluridae
Ameiurus natalis / + / + / +
Ameiurus nebulosus / +
Clariidae
Clarias batrachus* / + / +
Callichthyiidae
Hoplosterum littorale* / + / +
Cyprinodontidae
Fundulus chrysotus / + / + / + / + / + / +
Fundulus confluentus / + / +
Jordanella floridae / + / + / + / + / + / +
Lucania goodie / + / + / + / + / + / +
Poeciliidae
Belonesox belizanus* / +
Gambusia holbrooki / + / + / + / + / + / +
Heterandria formosa / + / + / + / + / + / +
Poecilia latipinna / + / + / + / + / +
Atherinidae
Labidesthes sicculus / +
Centrarchidae
Elassoma evergladei / +
Enneacanthus gloriosus / + / +
Chaenobryttus gulosus / + / + / + / + / +
Lepomis macrochirus / + / + / + / + / +
Lepomis marginatus / + / + / + / +
Lepomis microlophus / + / + / + / +
Lepomis punctatus / + / + / +
Micropterus salmoides / + / + / +
Percidae
Etheostoma fusiforme / + / + / + / +
Cichlidae
Astronotus ocellatus* / +
Cichlasoma bimaculatum* / + / + / + / + / + / +
Cichlasoma uropthalmus* / + / + / + / + / +
Oreochromis aureus* / + / + / + / +
Tilapia mariae* / + / + / + / +

* Non-native fish species

Kristine, Dunker, Florida Atlantic University Environmental Sciences, 2912 College Avenue, Davie, FL, 33314, Phone: 954-236-1115, Fax: 954-236-1099, , Invasive and Exotic Species

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