|Habitat use by fishes after tidal reconnection of an impounded estuarine wetland in the Indian River Lagoon, Florida (USA)|
Poulakis, G.R.; Shenker, J.M.; Taylor, D.S. (2002). Habitat use by fishes after tidal reconnection of an impounded estuarine wetland in the Indian River Lagoon, Florida (USA). Wetlands Ecol. Manag. 10: 51-69
In: Wetlands Ecology and Management. Springer: Den Haag; Dordrecht; Hingham, MA; Amsterdam. ISSN 0923-4861, more
|Authors|| || Top |
- Poulakis, G.R.
- Shenker, J.M.
- Taylor, D.S.
Most of the wetlands located along the Indian River Lagoon (IRL) in east-central Florida (USA) have been impounded since the 1950’s and 1960’s to reduce mosquito reproduction. Impounded marsh (i.e., impoundment) dikes physically separate the wetlands from the estuary to allow artificial flooding of the impoundments during the mosquito breeding period (May to October). Presently, Rotational Impoundment Management (RIM) is the preferred impoundment management technique in the IRL. Impoundments maintained under RIM have culverts installed through the dikes which are kept closed during the mosquito breeding season (to control mosquitos) and are allowed to remain open for the remainder of the year (to allow tidal flow). A 24.3 ha impoundment 8 km north of Sebastian Inlet that had been isolated from the IRL for over 39 years was studied for 12 months to determine habitat use by fishes after tidal reconnection and the implementation of RIM. Fish sampling was conducted with a seine in the perimeter ditch and with clover and minnow traps in the upper marsh and tidal creek areas of the impoundment. Water level, impoundment bottom topography, and the seasonal nursery function of the impoundment were factors that contributed to observed patterns of fish habitat use during the study. Within the first 15 weeks of perimeter ditch sampling, an increase from 9 to 40 species was observed. Transient species used the perimeter ditch almost exclusively and entered the impoundment primarily during the spring open period. Juvenile Pogonias cromis (Linnaeus), Elops saurus Linnaeus, Centropomus undecimalis (Bloch), and Megalops atlanticus Valenciennes were the most abundant recreationally important species, respectively. Habitat use by the most abundant resident species (Gambusia holbrooki Girard, Poecilia latipinna (Lesueur), Cyprinodon variegates Lacepède, and Fundulus confluentus Goode & Bean) was influenced primarily by water level fluctuations. Resident species used the upper marsh and tidal creek habitats during summer flooded periods and the cyprinodontids left the interior surface of the impoundment last as water levels decreased. This study is the first to document the recovery of fish populations in a reconnected impoundment north of Sebastian Inlet using both active and passive sampling techniques.