Factors Influencing Colonization and Survival of Juvenile Blue Crabs Callinectes sapidus in Southeastern U.S. Tidal Creeks

Abstract

Tidal creeks along the southeastern U.S. and Gulf of Mexico coastlines provide nursery habitats for commercially and ecologically important nekton, including juvenile blue crabs Callinectes sapidus, a valuable and heavily landed seafood species. Instream and watershed urbanization may influence the habitat value that tidal creeks provide to blue crabs. We investigated natural and anthropogenic factors influencing juvenile blue crab occupancy dynamics in eight first-order tidal creeks in coastal North Carolina (USA). An auto-logistic hierarchical multi-season (dynamic) occupancy model with separate ecological and observation sub-models was fitted to juvenile blue crab presence/absence data collected over replicate sampling visits in multiple seasons at three fixed trapping sites in each creek. Colonization and survival are the processes operating on occupancy that are estimated with this formulation of the model. Covariates considered in the ecological sub-model included watershed imperviousness, the percent of salt marsh in each creek’s high tide area, percent salt marsh edge, site-level water depth, and site-level salinity. Temperature, salinity, and dissolved oxygen were covariates considered in the observation sub-model. In the ecological sub-model, watershed imperviousness was a meaningful negative covariate and site-level salinity was a positive covariate of survival probability. Imperviousness and salinity were each marginally meaningful on colonization probability. Water temperature was a positive covariate of detection probability in the observation sub-model. Mean estimated detection probability across all sites and seasons of the study was 0.186. The results suggest that development in tidal creek watersheds will impact occupancy dynamics of juvenile blue crabs. This places an emphasis on minimizing losses of natural land cover classes in tidal creek watersheds to reduce the negative impacts to populations of this important species. Future research should explore the relationship between imperviousness and salinity fluctuations in tidal creeks to better understand how changing land cover influences water chemistry and ultimately the demographics of juvenile blue crabs.

Environmental drivers of size-based population structure, sexual maturity and fecundity: A study of the invasive blue crab Callinectes sapidus (Rathbun, 1896) in the Mediterranean Sea

“…Shallow subtidal areas of saltmarsh are known to be inhabited by the blue crab C. sapidus in their native areas [36][37][38][39]. Although blue crabs have been reported to move into the intertidal zone of polyhaline [40,41] and oligohaline waters [42], there are few data on the extent of intertidal salt marshes used by this large decapod crustacean in the Mediterranean Sea.…”

Model-based evaluation of critical nursery habitats for juvenile blue crabs through ontogeny: abundance and survival in seagrass, salt marsh, and unstructured bottom

“…Elevated abundance and survival of juvenile blue crabs in seagrass beds relative to unstructured habitats led multiple investigators to conclude that seagrass beds were the preferred initial nursery habitat (Orth and van Montfrans, 1987;Lipcius et al, 2005;Ralph et al, 2013). In regions where seagrass beds were locally sparse or absent from the estuarine habitat mosaic, blue crabs opportunistically exploited salt marshes, macroalgae, and other alternative nurseries (Wilson, Able and Heck Jr, 1990a,b;Thomas, Zimmerman and Minello, 1990;Posey et al, 2005;Johnson and Eggleston, 2010;Rudershausen, Merrell and Buckel, 2021). Although juvenile survival is higher in structured habitats, juvenile growth rates appear higher in turbid marshfringed habitats distant from SAV beds (Seitz et al, 2003;Seitz, Lipcius and Seebo, 2005;Lipcius et al, 2005).…”

“…Meanwhile, abundances of larger (i.e. >15 mm CW) size classes are higher in salt marshes (Ralph, 2014;Rudershausen, Merrell and Buckel, 2021;Hyman et al, 2022Hyman et al, , 2023. Although less structurally complex than seagrass beds, salt marsh shoot density impedes foraging success of subadult and adult blue crab predators on conspecific juveniles in predation experiments (Johnston and Caretti, 2017;Miller et al, 2023).…”