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Modifying mosquito impoundment management to enhance nursery habitat value for juvenile common Snook (Centropomus undecimalis) and Atlantic tarpon (Megalops atlanticus)

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  • Bonefish & Tarpon Trust and Florida Atlantic University
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Abstract and Figures

Coastal wetlands function as nurseries for juveniles of many fishes, including common snook (Centropomus undecimalis) and Atlantic tarpon (Megalops atlanticus). Thousands of hectares of mangrove habitat in the Indian River Lagoon (IRL), Florida (USA) have been impounded for mosquito control, limiting connectivity and potentially decreasing nursery habitat value. Many impoundments are managed to provide connectivity through culverts to the IRL from October through April (non-breeding season for mosquitos), with the impoundments isolated and filled with water to control mosquito breeding from May through September. To determine whether seasonality of impoundment-estuary connectivity affected nursery habitat value, we conducted a quantitative assessment of the emigration of juvenile snook and tarpon from Bee Gum Point, a mosquito impoundment in the IRL. A total of 305 snook and 103 tarpon were captured within the impoundment and marked with passive integrated transponder (PIT) tags. Pairs of tag-detecting antennas were established at culverts in two basins within the impoundment and monitored for 2 years. Only four tagged snook, and no tagged tarpon, were physically recaptured, while nearly 71% of the tagged snook and 77% of the tagged tarpon were detected at least once by antennas on the inside of the impoundment. Antennas on the outside of the culverts detected only 18 snook and eight tarpon emigrating through the culverts during 418 days of two open seasons. When culverts were experimentally opened for a total of 21 days in three periods during two summers, both snook (n = 49) and tarpon (n = 22) emigrated at far higher rates that they did during the normal open season. This significant increase in emigration indicates the importance of managing habitat connectivity to correspond to natural seasonal emigration patterns to increase the productivity of these fish nurseries.
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Modifying mosquito impoundment management to enhance
nursery habitat value for juvenile common Snook
(Centropomus undecimalis) and Atlantic tarpon
(Megalops atlanticus)
Anthony C. Cianciotto &Jonathan M. Shenker &
Aaron J. Adams &Jacob J. Rennert &David Heuberger
Received: 14 February 2018 /Accepted: 17 December 2018 /Published online: 8 January 2019
#Springer Nature B.V. 2019
Abstract Coastal wetlands function as nurseries for ju-
veniles of many fishes, including common snook
(Centropomus undecimalis) and Atlantic tarpon
(Megalops atlanticus). Thousands of hectares of man-
grove habitat in the Indian River Lagoon (IRL), Florida
(USA) have been impounded for mosquito control, lim-
iting connectivity and potentially decreasing nursery hab-
itat value. Many impoundments are managed to provide
connectivity through culverts to the IRL from October
through April (non-breeding season for mosquitos), with
the impoundments isolated and filled with water to con-
trol mosquito breeding from May through September. To
determine whether seasonality of impoundment-estuary
connectivity affected nursery habitat value, we conducted
a quantitative assessment of the emigration of juvenile
snook and tarpon from Bee Gum Point, a mosquito
impoundment in the IRL. A total of 305 snook and 103
tarpon were captured within the impoundment and
marked with passive integrated transponder (PIT) tags.
Pairs of tag-detecting antennas were established at
culverts in two basins within the impoundment and mon-
itored for 2 years. Only four tagged snook, and no tagged
tarpon, were physically recaptured, while nearly 71% of
the tagged snook and 77% of the tagged tarpon were
detected at least once by antennas on the inside of the
impoundment. Antennas on the outside of the culverts
detected only 18 snook and eight tarpon emigrating
through the culverts during 418 days of two open sea-
sons. When culverts were experimentally opened for a
total of 21 days in three periods during two summers,
both snook (n=49)andtarpon(n= 22) emigrated at far
higher rates that they did during the normal open season.
This significant increase in emigration indicates the im-
portance of managing habitat connectivity to correspond
to natural seasonal emigration patterns to increase the
productivity of these fish nurseries.
Keywords Snook .Tar po n .Nursery.Habitat .
Impoundment .Emigration
Introduction
Many species of coastal and reef fishes undergo a series
of ontogenetic habitat shifts throughout their life cycle
(Peters et al. 1998; Adams et al. 2006a), often using
coastal regions as nursery habitats. These nurseries in-
clude mangrove habitats in tropical and semi-tropical
regions, which provide juvenile fishes with shelter from
predators, and access to prey (Beck et al. 2001;
Nagelkerken et al. 2001; Poulakis et al. 2002;Lewis
and Gilmore 2007;Adamsetal.2009;Judetal.2011).
Environ Biol Fish (2019) 102:403416
https://doi.org/10.1007/s10641-018-0838-8
A. C. Cianciotto :A. J. Adams :D. Heuberger
Harbor Branch Oceanographic Institute, Florida Atlantic
University, 5600 US-1, Fort Pierce, FL 34946, USA
J. M. Shenker (*):J. J. Rennert
Ocean Engineering and Marine Sciences, Florida Institute of
Technology, 150 W University Blvd, Melbourne, FL 32901, USA
e-mail: shenker@fit.edu
A. J. Adams
Bonefish & Tarpon Trust, 135 San Lorenzo Avenue, Suite 860,
Coral Gables, FL 33146, USA
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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