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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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Anthony C. Cianciotto
Anthony C. Cianciotto
Anthony C. Cianciotto
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Jonathan Shenker at Florida Institute of Technology
Jonathan Shenker
Aaron J. Adams at Bonefish & Tarpon Trust and Florida Atlantic University
Aaron J. Adams
  • Bonefish & Tarpon Trust and Florida Atlantic University
Jacob Rennert at National Oceanic and Atmospheric Administration
Jacob Rennert
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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) 102:403–416
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.
... Herke et al., 1992). In addition, specific marsh management strategies such as those used to promote waterfowl (Carswell et al., 2015) and control mosquitoes (Rey et al., 2012), including seasonal water-level manipulations with prescribed volumes of tidal exchange, rarely consider impacts on fishes, and commonly result in poor quality fish habitat and impediments to fish migration (Cianciotto et al., 2019). It should be noted, however, that managed marshes may serve as valuable nursery habitats for some marine species during their period of estuarine residency, especially where natural estuarine habitats are scarce (e.g. ...
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... We excluded SIRL from this comparison because relative changes in mangrove cover or saltmarsh cover were not differentiated. In NIRL, system-wide mosquito impoundment networks have fragmented and at least partially disconnected most coastal wetland habitats from the estuary (Cianciotto et al. 2019). As such, for NIRL, impounded mangroves and saltmarshes were considered habitat that was no longer fully functional for snook. ...
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... Both fishes use a mosaic of coastal wetland habitat during their early life history, which is context dependent and influenced by coastal geomorphology. For example, the habitat types used by juvenile snook, whether riverine backwaters, tidal creeks, coastal ponds, or mangrove impoundments (Stevens et al. 2010;Brame et al. 2014;Cianciotto et al. 2019), are influenced by habitat availability within a given estuary and proximity to ocean passes (Stevens et al. 2007;Trotter et al. 2021;Wilson et al. 2023). The transparent, ribbon-like larvae of tarpon allow the species to occupy deep depressions in coastal wetlands away from the open water of the estuary (Mace et al. 2018;Elmo et al. 2021;Kimball et al. 2021). ...
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Full-text available
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To conserve or restore juvenile fish habitat, resource managers, restoration practitioners, and engineers need fine-scale information to understand what conditions they need to preserve or what specifications are needed to create new habitat. The objective of this study was to develop statistical models using a dataset of 18 coastal ponds in Southwest Florida, USA, to predict the abundance of juvenile common snook Centropomus undecimalis (hereafter snook) and presence of juvenile tarpon Megalops atlanticus , both of which are flagship species used for conservation and restoration of subtropical and tropical wetlands. Model predictors included water conditions and characteristics of vegetation, sediment, and geographic position. Modeling results indicated that juvenile snook used coastal ponds that were directly connected to tidal creeks. In contrast, juvenile tarpon were more likely to be present in coastal ponds that were separated from tidal creeks by dense mangrove forest (e.g., elevation > 0.48 m above Mean Low Water) characterized by highly organic sediment and low dissolved oxygen, to which tarpon are well adapted. Overlap between snook abundance and tarpon presence was greatest where connections between ponds and the nearest tidal creek were at a relatively low elevation (e.g., -0.12 m relative to Mean Low Water). Although these findings are most applicable to management and conservation of populations in areas along the Gulf coast of Florida (i.e., in areas of similar tidal range and coastal geomorphology), incorporating more detailed habitat surveys to better capture landscape context, geomorphology, and connectivity into fish sampling designs should be broadly applicable to estuarine fish ecology.
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... Juvenile Tarpon rely exclusively on coastal wetlands, which consist of a mosaic of pond and creek habitats, often with fringing vegetation, a mix of water depths, variable freshwater inflow, and restricted connection to the estuary that inhibits access by predatory fishes (Cyr 1991;Adams and Murchie 2015). The earliest life stages occupy estuarine impoundments, mangrove-lined ponds, and salt marsh pools (Robins 1977;Mace et al. 2018;Cianciotto et al. 2019), which maintain connection with the ocean for only brief periods of high water (Wade 1962). These stagnant pools and ponds experience highly variable salinities, periods of extremely shallow water, high hydrogen sulfide concentrations, and anoxia (Wade 1962;Robins 1977;Cyr 1991). ...
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Article
Full-text available
  • Aug 2024
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... Early life stage tarpon Megalops atlanticus have been documented along the southeastern US Atlantic coast in estuaries of Florida (Shenker et al. 2002;Reyier and Shenker 2007;Korsman et al. 2017;Cianciotto et al. 2019;Wilson et al. 2019), Georgia (Wade 1962;Rickards 1968), South Carolina (McGovern andWenner 1990; Robinson and Jennings 2014;Mace et al. 2018;Kimball et al. 2021), andNorth Carolina (Hildebrand 1934;Wade 1962;Tucker and Hodson 1976;Hettler and Chester 1990;Schwartz 2002). Many of these studies collected early life stage tarpon as part of research focused on fish assemblages in natural and managed estuarine habitats. ...
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... Tidal circulation is done in winter, followed by complete flooding of the marsh during spring. Compared to impounded marshes, RIM provides better water quality, benefits salt-tolerant plants, marsh typical zooplankton and fish communities (Brockmeyer et al. 1997;Cianciotto et al. 2019). Besides RIM, OMWM is applied in previously ditched marshes principally along the east coast of the USA (Dale and Knight 2008). ...
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... In the Indian River Lagoon on the east coast of Florida, over 16,000 ha of coastal marshes were impounded in the 1950s and 1960s for the control of mosquito breeding (Brockmeyer et al. 1996), and 85% of the mangrove habitats of the ecosystem are located within these impoundments (FWC 2021). Subsequent installation of culverts in many of the mangrove-filled impoundments, and seasonal control of hydrographic connectivity allowed some of the fish nursery functionality to be restored (Gilmore et al. 1982;Brockmeyer et al. 1996;Poulakis et al. 2002;Cianciotto et al. 2019). Since ecologically intact systems are more resilient to disturbances and the interaction between natural and anthropogenic disturbances are especially problematic for maintaining ecological integrity (White and Jentsch 2001), the compromised state of the coastal habitat mosaic will mean an even greater challenge to managing fish species that support flats fisheries. ...
View
... In the Indian River Lagoon on the east coast of Florida, over 16,000 ha of coastal marshes were impounded in the 1950s and 1960s for the control of mosquito breeding (Brockmeyer et al. 1996), and 85% of the mangrove habitats of the ecosystem are located within these impoundments (FWC 2021). Subsequent installation of culverts in many of the mangrove-filled impoundments, and seasonal control of hydrographic connectivity allowed some of the fish nursery functionality to be restored (Gilmore et al. 1982;Brockmeyer et al. 1996;Poulakis et al. 2002;Cianciotto et al. 2019). Since ecologically intact systems are more resilient to disturbances and the interaction between natural and anthropogenic disturbances are especially problematic for maintaining ecological integrity (White and Jentsch 2001), the compromised state of the coastal habitat mosaic will mean an even greater challenge to managing fish species that support flats fisheries. ...
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... Atlantic tarpon (hereafter tarpon) use natural and managed habitats as juveniles before emigrating to marine habitats and are frequently found in estuarine impoundments, ponds, and pools in and around South Florida and the Caribbean (Zerbi et al. 2005;Cianciotto et al. 2019;Wilson et al. 2019), as well as farther north in estuaries along the southeastern US Atlantic (i.e., South Carolina and Georgia;Nichols 1994;Robinson and Jennings 2014;Mace et al. 2018) and Gulf coasts (Stein et al. 2016). Managed marsh impoundments are designed to maintain consistent environmental conditions (e.g., depth), with water control structures limiting tidal influence and water flow according to seasonal operation protocols, but on occasion external forces (e.g., severe storms, drought) can combine with internal operations (e.g., low or no water flow) to create extreme water temperature, salinity, or dissolved oxygen conditions (McGovern and Wenner 1990;Robinson and Jennings 2014). ...
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Article
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  • Feb 2022
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Recruitment and Habitat Use of Early Life Stage Tarpon (Megalops atlanticus) in South Carolina Estuaries
Article
Full-text available
  • May 2018
Our study was designed to examine early life stage tarpon (Megalops atlanticus) recruitment, habitat use, and residency in coastal environments near the northern limit of their distribution in the western Atlantic Ocean. We employed a multi-faceted approach to (1) collect ingressing larval tarpon on nighttime flood tides at multiple sites, (2) document larval and juvenile tarpon use of natural high marsh pools, and (3) examine juvenile tarpon movement and behavior in managed marsh impoundments, all in the North Inlet-Winyah Bay estuarine system of South Carolina, USA. The timing of recruitment (June through November) and size of larvae (mean ± standard deviation = 23 ± 3 mm standard length [SL]) during estuarine ingress was similar to that reported from other subtropical locations in the region. Soon after recruiting into the system, larval and small juvenile tarpon (47 ± 25 mm SL) co-occurred in high marsh pools from July to November, and large juveniles (201 ± 34 mm SL) were also present in marsh impoundments during this same time period. An increase in tarpon length over time during their residency in high marsh pools and the relatively large size they attain in marsh impoundments indicate these environments may function as favorable nursery habitats. As water temperatures decreased during October and November, juvenile tarpon emigrated from these estuarine habitats. Tarpon appear to use a variety of estuarine habitats in coastal South Carolina from summer through late fall during their early life stage development. The fate of these individuals after they leave estuarine habitats at the onset of winter in this region is currently unknown.
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Reproduction and early life history of common snook, Centropomus undecimalis (Bloch), in Florida
Conference Paper
  • Mar 1998
  • B MAR SCI
This paper combines published literature and unpublished Florida Department of Environmental Protection (FDEP) data on snook reproduction and early life history. Published literature originally dealt with fisheries investigations (1950s) and freshwater culture (1970s) but has expanded to include marine stock enhancement, spawning, and larval and juvenile ecology. In addition, ongoing FDEP projects provide considerable information. Snook are protandric hermaphrodites that probably spawn near river mouths, passes (inlets), and points of land in central and southern Florida estuaries. Females are older and larger than males at 50% maturity (5 yrs and 500-522 mm SL versus about 2 yrs and 330-348 mm SL) and have group synchronous ovarian development. The spawning season is long (approx. April to December or January) and includes multiple spawnings. Most spawning occurs between May and September. Spring spawning occurs at water temperatures >22 degrees C and salinities >27 parts per thousand. Several researchers noted increased spawning activity around the times of spring and summer new or full moons. In prespawning behavior, females are escorted by a number of(usually) smaller males, but actual spawning has not been documented. In the laboratory, eggs averaged 0.70 mm diameter and hatched in 17-18 h at temperatures of 26-29 degrees C and salinities of 28-38 parts per thousand. Newly hatched larvae (1.4-1.5 mm notochord length) spend similar to 2.5 wks in nearshore waters before their arrival at shallow-water nursery sites. Eggs have been collected during field studies in only one secondary embayment of lower Tampa Bay, but preflexion larvae have been taken in lower Tampa Bay and just off the beach at Naples. Postflexion larvae have been reported from both coasts of Florida, but only 16 larvae are listed in published literature. Late-stage larvae recruit to vegetated shorelines of quiet, shallow-cater creeks, canals, and lagoons in both low-salinity (riverine) and high-salinity (mangrove swamp and salt marsh) environments. Early juvenile-stage snook occupy a spatiality restricted microhabitat along shores having limited water movement, moderate shoreline slopes, and vegetation extending over and/or into the water; as the juveniles grow, their habitat becomes less defined and restricted. Early juveniles (<40 mm SL) feed on copepods and other microcrustaceans, but later juveniles (40-50 mm SL) switch to small fish (mainly poeciliids and cyprinodontids) and crustaceans (mainly palaemonid shrimp). Factors other than fishing regulations that affect survival of adult snook include human impacts on habitat quantity and quality and natural perturbations such as cold kills and red tides. Some of these same factors may also affect the survival of larval and juvenile snook.
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Age, growth, maturation, and protandric sex reversal in common snook, Centropomus undecimalis, from the east and west coasts of South Florida
Article
  • Jul 2000
  • FISH B-NOAA
During 1986-91, we examined 2088 common snook, Centropomus undecimalis, captured in Jupiter and Lake Worth inlets and adjacent waters on the east coast of Florida and 1784 common snook captured in Tampa Bay on the west coast of Florida. Offish that were sexed, females ranged in length from 397 to 1105 mm FL, and males ranged from 124 to 925 mm FL. East coast fish were larger overall than west coast fish. Age of common snook was determined from sectioned otoliths. Results from the return of 80 oxytetracycline-marked otoliths combined with analyses of monthly patterns in marginal increments and the percentage of otoliths with an annulus on the edge, demonstrated that a single annulus is formed each year. Common snook can live to 21 years, but most of the fish in our sample were from 1 to 7 years old. The von Bertalanffy growth models were significantly different (P<0.001) for each coast and suggested that east coast snook grow faster than west coast snook. Common snook are protandric hermaphrodites. The gonads of 27 transitional specimens contained both degenerating spermatogenic and developing ovarian tissue, and sex reversal was observed in captive common snook. Common snook sex ratios and length-frequency distributions were also consistent with a diagnosis of protandric hermaphroditism. Females smaller than 500 mm FL were uncommon, and only one female less than 400 mm long was captured. The predicted lengths and ages at which 50% of the fish in the population would be females were 767 mm FL and 7.4 years for the east coast and 608 mm FL and 5.1 years for the west coast, some males on both coasts were sexually mature at lengths less than 200 mm FL and at age 0; most age-1 males were mature on both coasts. All females were considered mature because they were derived from post-spawning males.
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