Larval fishes of a Middle Atlantic Bight estuary: assemblage structure and temporal stability

We collected weekly, quantitative ichthyoplankton samples over 6 years (1989-1994, 1309 samples) to identify temporal scales of variability in the abundance and occurrence of larval fish assemblages near Little Egg Inlet in southern New Jersey, U.S.A. We collected species that spawn in the estuary (30%), both the estuary and continental shelf (35%), continental shelf (25%), and the Sargasso Sea (10%). The following analyses suggest an annually repeated seasonal progression of species assemblages: (i) the rank abundance of the 20 dominant species did not change significantly from year to year, (ii) variation in the density of the dominant species was primarily explained by intraannual rather than interannual variation, and (iii) multivariate analysis of the assemblage matrix identified five seasonal assemblages that occurred during all six years. We found that the timing and duration of each of these seasonal groups were correlated with two characteristics of the annual temperature cycle, magnitude (higher or lower temperature) and trajectory (increasing vs decreasing temperature). We suggest that the repeated occurrence of larval fish assemblages in temperate estuaries along the U.S. coast may, in part, be driven by local environmental processes.

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Consequences of plume encounter on larval fish growth and condition in the Gulf of Mexico

Marine Ecology Progress Series ◽

10.3354/meps13396 ◽

2020 ◽

Vol 650 ◽

pp. 63-80 ◽

Cited By ~ 1

Author(s):

KE Axler ◽

S Sponaugle ◽

F Hernandez ◽

C Culpepper ◽

RK Cowen

Keyword(s):

Gulf Of Mexico ◽

Continental Shelf ◽

Prey Capture ◽

Larval Fish ◽

Fish Larvae ◽

Fish Growth ◽

Frequency Distributions ◽

Larval Fishes ◽

River Estuarine ◽

Anchoa Hepsetus

Freshwater input into nearshore continental shelf waters from coastal river-estuarine plumes can greatly alter the physical and trophic environments experienced by fish larvae. However, the biological consequences of plume encounter on larval fish survival remain equivocal, largely due to the extreme variability of these systems but also because traditional sampling techniques alone are too coarse to effectively characterize the dynamic biophysical environment at spatiotemporal scales relevant to individual larvae. Using a multidimensional approach, we simultaneously collected in situ imagery and net samples of larval fishes and zooplankton from the Mobile Bay plume (Alabama, USA) and ambient continental shelf waters during a high discharge event (8-11 April 2016). We measured the effects of plume encounter on growth and condition of larval striped anchovy Anchoa hepsetus and sand seatrout Cynoscion arenarius, 2 prominent nearshore species in the northern Gulf of Mexico. Size-frequency distributions of both species indicated that larger individuals were present in shelf waters but absent from plume waters. Otolith microstructure analysis revealed that recent growth of both focal species was significantly lower for plume-collected larvae during the last few days prior to capture. Furthermore, plume larvae were in poorer morphometric condition (skinnier at length) than their shelf counterparts, despite the fact that there were higher concentrations of zooplankton prey in plume water masses. Taken together, these results suggest that elevated prey concentrations do not necessarily translate to higher growth and condition. High turbulence and turbidity within the plume may physically inhibit the prey capture ability and feeding success of fish larvae.

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Assemblage Structure of Larval Fishes in Epipelagic and Mesopelagic Waters of the Northern Gulf of Mexico

Frontiers in Marine Science ◽

10.3389/fmars.2021.766369 ◽

2021 ◽

Vol 8 ◽

Author(s):

Verena H. Wang ◽

Carley R. Zapfe ◽

Frank J. Hernandez

Keyword(s):

Gulf Of Mexico ◽

Environmental Conditions ◽

Early Life ◽

Fish Assemblages ◽

Larval Fish ◽

Critical Role ◽

Life Stages ◽

Early Life Stages ◽

Northern Gulf Of Mexico ◽

Larval Fishes

The early life stages of fishes play a critical role in pelagic food webs and oceanic carbon cycling, yet little is known about the taxonomic composition and distribution of larval fishes in the northern Gulf of Mexico (GOM) below the epipelagic (<200 m). Here, we provide the first large-scale characterization of larval fish assemblages in the GOM across epipelagic, mesopelagic, and bathypelagic regions (0–1,500 m), using samples collected during the Natural Resource Damage Assessment conducted following the Deepwater Horizon oil spill (DWHOS). These data contain > 130,000 ichthyoplankton specimens from depth-discrete plankton samples collected across 48 stations in the GOM during six cruises conducted in 2010 and 2011. We examined indices of abundance and diversity, and used a multivariate regression tree approach to model the relationship between larval fish assemblages and environmental conditions. The total abundance of larval fish followed a generally decreasing trend with increasing depth, and family-level richness and diversity were significantly higher in the epipelagic than mesopelagic and bathypelagic regions. Fourteen distinct assemblage groups were identified within the epipelagic, with depth, surface salinity, and season contributing to the major branches separating groups. Within the mesopelagic, seven distinct assemblage groups were identified and were largely explained by variation in depth, season, and surface temperature. Bathypelagic assemblages were poorly described by environmental conditions. The most common epipelagic assemblage groups were widely distributed across the GOM, as were all mesopelagic assemblage groups, suggesting limited horizontal structuring of GOM larval fishes. Of the mesopelagic-associated fish taxa, four dominant families (Myctophidae, Gonostomatidae, Sternoptychidae, Phosichthyidae) comprised the majority of the catch in both the epipelagic (63%) and combined mesopelagic and bathypelagic (97%) regions. Dufrêne-Legendre indicator analysis confirmed that these dominant families were characteristic of epipelagic and mesopelagic assemblages; the larvae of less common mesopelagic-associated families largely identified with epipelagic assemblage groups. A lack of baseline data about the distribution patterns of early life stages of mesopelagic fishes in the GOM was apparent following the DWHOS, and these findings provide a valuable reference point in the face of future ecosystem stressors.

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Report on laboratory testing of shallow sediments, Middle Atlantic Outer Continental Shelf

Open-File Report ◽

10.3133/ofr78578 ◽

1978 ◽

Author(s):

Daniel P. LaGatta ◽

Karl Dalenberg ◽

H.J. Knebel ◽

D.A. Sangrey

Keyword(s):

Continental Shelf ◽

Laboratory Testing ◽

Outer Continental Shelf ◽

Middle Atlantic ◽

Shallow Sediments

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Juvenile fish assemblages in the Jinju Bay region, Korea

Fisheries and Aquatic Sciences ◽

10.1186/s41240-020-00175-6 ◽

2020 ◽

Vol 23 (1) ◽

Author(s):

Se Hun Myoung ◽

Seok Nam Kwak ◽

Jin-Koo Kim ◽

Won-Chan Lee ◽

Jeong Bae Kim ◽

...

Keyword(s):

Dominant Species ◽

Fish Assemblages ◽

Juvenile Fish ◽

Young Fish ◽

Monthly Basis ◽

Southern Korea ◽

Pleuronichthys Cornutus ◽

Pennahia Argentata ◽

Hemitripterus Villosus ◽

Number Of Individuals

AbstractAssemblages of juvenile fish and associated abiotic parameters were investigated inside and outside Jinju Bay in southern Korea, on a monthly basis from December 2014 to November 2015. Fluctuations in water temperature and salinity were larger inside than outside the bay. In total, 534,657 individuals per square kilometre from 81 fish species and 47 families were collected during the study period. The most dominant species was Nuchequula nuchalis both inside (25.6%) and outside (26.9%) the bay. The next dominant species were Thryssa kammalensis (17.9%) and Zoarces gillii (16.0%) inside the bay and Liparis tanakae (16.9%) and T. kammalensis (9.0%) outside the bay. Forty species (33% of total number of individuals) of young fish were recorded inside the bay and 47 species (52%) outside the bay. Therefore, it appears that a diversity of fish use nursery grounds inside and outside Jinju Bay. In particular, the following six species appeared: Z. gillii, Pleuronichthys cornutus, L. tanakae, Hemitripterus villosus, Pennahia argentata, and Xenocephalus elongates. Due to assemblage differences for fishes within Jinju Bay and outside the bay, management of both areas is required to maintain current diversity of species in the region.

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Temporal variation of larval fish assemblages of the Murray Mouth in prolonged drought conditions

Marine and Freshwater Research ◽

10.1071/mf12278 ◽

2013 ◽

Vol 64 (10) ◽

pp. 932 ◽

Cited By ~ 6

Author(s):

L. B. Bucater ◽

J. P. Livore ◽

C. J. Noell ◽

Q. Ye

Keyword(s):

Fish Assemblages ◽

Larval Fish ◽

River System ◽

Sampling Period ◽

Marine Species ◽

Flow Regulation ◽

Nursery Areas ◽

Transition Zones ◽

Murray Darling Basin ◽

Drought Conditions

Estuaries are transition zones that link freshwater and marine ecosystems and are often used as nursery areas by fish. The Murray–Darling Basin, which is heavily affected by flow regulation and water extraction, is the largest river system in Australia and terminates at the Murray Mouth estuary. Protracted drought conditions resulted in extremely low flows to the Murray Mouth that affected water condition, fish abundance, community structure and fish use of the estuary (e.g. nursery areas). The aims of the present study were to examine temporal changes in larval fish assemblages in this estuary. The assemblages were dominated by two gobiid species, Arenigobius bifrenatus and Tasmanogobius lasti. There was a noticeable absence or low abundance of freshwater, diadramous and large-bodied marine species that use this estuary for reproductive functions. Monthly differences in larval fish assemblages, between August–September and October–November, were attributed to increases in the abundances of A. bifrenatus in October and November and oscillation in T. lasti during the entire sampling period. The outcomes of the present study suggested that larval fish assemblages in drought conditions are limited to small-bodied species tolerant of high salinities and that freshwater flows are needed for the estuary to function as a nursery for other species.

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Interannual variability of larval fish assemblages associated with water masses in winter in the Taiwan Strait during 2007–2013

Fisheries Science ◽

10.1007/s12562-020-01489-z ◽

2021 ◽

Author(s):

Yu-Kai Chen ◽

Chia-Yi Pan ◽

Yi-Chen Wang ◽

Hsiu-Ju Tseng ◽

Bo-Kun Su ◽

...

Keyword(s):

Fish Assemblages ◽

Larval Fish ◽

Taiwan Strait ◽

Assemblage Structure ◽

Sea Surface ◽

Coastal Current ◽

Annual Variations ◽

Frontal Zones ◽

The Taiwan Strait

AbstractIn this study, the interannual variations of ichthyoplankton assemblages in the Taiwan Strait (TS) during the winters of 2007–2013 were determined. The cold China Coastal Current (CCC) and Mixed China Coastal Water (MCCW) intruded into the TS and impinged with the warm Kuroshio Branch Current (KBC) with annual variations. Consequently, the ichthyoplankton community in the TS was mainly structured into two assemblages characterized by differing environmental conditions. The composition of the warm KBC assemblage was relatively stable and was characterized by Diaphus B and Bregmaceros spp. By contrast, the cold MCCW assemblage demonstrated considerable variations over the years, with demersal Gobiidae and Scorpaenidae families considered the most representative. In addition, Benthosema pterotum and Trichiurus spp. were common in both KBC and MCCW assemblages. The distribution of the KBC assemblage demonstrated sharp boundaries in the frontal zones, whereas changes in the assemblage structure between the frontal zones were gradual for the MCCW assemblage, particularly when demersal taxa were dominant. Sea surface temperature and salinity were most strongly associated with variability in the assemblage structure during the study period. Thus, this paper provides a better understanding of long-term larval fish dynamics during winter in the TS.

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Distribution of paracalanidae species (Copepoda, Crustacea) in the continental shelf off Sergipe and Alagoas States, Northeast Brazil

Brazilian Journal of Oceanography ◽

10.1590/s1679-87592006000300001 ◽

2006 ◽

Vol 54 (4) ◽

pp. 173-181 ◽

Cited By ~ 12

Author(s):

Hortência Maria Pereira Araujo

Keyword(s):

Continental Shelf ◽

Rainy Season ◽

Environmental Variables ◽

Dominant Species ◽

Seasonal Distribution ◽

Northeast Brazil ◽

Oceanic Water ◽

Density Values ◽

Oceanic Species ◽

Parvocalanus Crassirostris

The spatial and seasonal distribution of the Paracalanidae species were studied in eighteen stations in the continental shelf off Sergipe and Alagoas States, northeast Brazil, in December, 2001 and 2003, and in June, 2002 and 2003. The Paracalanidae family was constituted by coastal and shelf species such as Parvocalanus crassirostris, Paracalanus quasimodo, P. indicus and P. aculeatus and oceanic species, Calocalanus pavo and Acrocalanus longicornis. Density values were higher in stations located at 10 m isobath with respect to those located at 20 and 30 m depths. Paracalanidae abundance presented differences between seasons with values higher in June (2002, 2003) than in December (2001, 2002). All species were more abundant in the rainy season except Parvocalanus crassirostris. Paracalanus quasimodo was the dominant species with average densities of 949, 740 and 41 ind.m-3 in December months and 4231, 2389 and 1185 ind.m-3 in June months, at stations with local depths of 10, 20 and 30 m, respectively. Canonical correspondence analysis showed that salinity and temperature were the environmental variables that presented significant correlation with the distribution of Paracalanidae species, probably because these variables are influenced by the estuarine waters and by the dynamic of oceanic water masses in the continental shelf.

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ICHTHYOFAUNA IN THE INNER CONTINENTAL SHELF NEXT TO THE PARANAGUÁ ESTUARINE COMPLEX, SOUTHERN BRAZIL

Boletim do Instituto de Pesca ◽

10.20950/1678-2305.2020.46.4.603 ◽

2021 ◽

Vol 46 (4) ◽

pp. 1-13

Author(s):

Cesar SANTOS ◽

Roberto SCHWARZ JUNIOR ◽

Helen Audrey PICHLER ◽

Olímpio Rafael CARDOSO ◽

Marcelo Renato LAMOUR ◽

...

Keyword(s):

Continental Shelf ◽

Fish Assemblages ◽

Fish Fauna ◽

Temporal Variations ◽

Otter Trawl ◽

Rainfall Regime ◽

Wet Season ◽

Environmental Characteristics ◽

The North ◽

Inner Continental Shelf

The composition and structure of fish assemblages in the inner continental shelf of the Paraná State are affected by cold fronts and the rainfall regime. Data from fishing activities in this region, as well as the analysis of environmental characteristics, are the main tools available for understanding fish dynamics, under influence of increasing human activities. In order to better understand patterns and temporal variations in fish assemblages in the inner continental shelf of the Paraná State, a total of 24 double trawls were performed with an otter trawl between August 2000 and July 2001, in two sampling areas, the North area in front of the northern mouth of the Paranaguá Estuary Complex, and the South area, in front of the Leste beach. A total of 45,277 fish specimens belonging to 35 families and 97 species were caught. Sciaenidae was the most abundant family, with 37.1% of the total number of individuals caught, and with the highest richness (18 species). Statistical analyses evidenced significant differences in environmental characteristics and in fish fauna, and that both areas disturbances were observed in the fish assemblages during the dry and wet season, being more intense in the Southern area, disturbances that would be related to the shrimp fishing present in the two areas sampled in this study.

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