Spawning and transport dynamics of Atlantic menhaden: inferences from characteristics of immigrating larvae and predictions of a hydrodynamic model

Abstract

We examined patterns of abundance, age and spawning date distributions of Atlantic menhaden Brevoortia tyrannus larvae immigrating during two seasons through three North Carolina inlets—Oregon, Ocracoke and Beaufort—to elucidate their spawning and transport dynamics. These patterns were examined in conjunction with corresponding predictions from a three‐dimensional, wind‐and tide‐driven hydrodynamic model. Larvae immigrating through different inlets showed consistent similarities as well as marked differences in temporal patterns of abundance, spawning dates and transport times. Intraseasonal patterns in abundance and spawning date distributions among inlets suggest that, in both study years, the spatio‐temporal dynamics of menhaden immigration were driven by large‐scale patterns along the Atlantic coast, rather than by localized variation in spawning activity. Interannual differences in the temporal patterns of spawning dates and larval immigration indicate interannual differences in transport dynamics and/or the spatial‐temporal distribution of spawning. When the spawning locations predicted by the hydrodynamic model are interpreted in conjunction with advanced very high resolution radiometer sea‐surface temperature information, the results are consistent with the limited historical information available on spatio‐temporal distribution of Atlantic menhaden eggs and larvae. The transport model also predicted distributions of arrival times for immigrating larvae that were comparable in range and variability with observed patterns. Our use of data from immigrating larvae, coupled with a hydrodynamic transport model and sea‐surface temperatures, allowed us to uncover relationships between spatio‐temporal patterns of Atlantic menhaden spawning and transport dynamics that could not have been identified by either approach alone.

Anguilla rostrata glass eel ingress into two, U.S. east coast estuaries: patterns, processes and implications for adult abundance

“…Atlantic Ocean water flows into the estuary through Beaufort Inlet and c. 10% moves up the channel that provides water to the Radio Island–Pivers Island channel (Churchill et al , 1999). A number of studies indicate species composition and abundance of samples taken from Beaufort Inlet are characteristic of collections from adjacent inlets and surrounding sounds (Lewis & Mann, 1971; Hettler et al , 1997; Hettler & Hare, 1998; Forward et al , 1999; Rice et al , 1999).…”

Life history and habitat use of the speckled worm eel, Myrophis punctatus, along the east coast of the United States

“…Seasonal temperature variation is 8-30°C and tidal range is about 1 m. Samples were collected from a bridge that spans a 40 m wide channel (water depth about 4 m) about 1.5 km inside of Beaufort Inlet (Churchill et al 1999). Species composition and abundance of samples taken from Beaufort Inlet are characteristic of collections from adjacent inlets and surrounding sounds (Lewis and Mann 1971;Warlen and Burke 1990;Hettler et al 1997;Hettler and Hare 1998;Forward et al 1999;Rice et al 1999).…”

Physical oceanography of the North Carolina continental shelf during the fall and winter seasons: implications for the transport of larval menhaden

“…Net transport resulting from the coupling between the active vertical migration of larvae and the flow field is discussed by Hoss et al . (1989 ), Rice et al . (1999 ) and Hare et al .…”