Early Life History of Pomatomus saltatrix off the East Coast of South Africa

1996 ◽  
Vol 47 (2) ◽  
pp. 319 ◽  
Author(s):  
LE Beckley ◽  
AD Connell
Keyword(s):  
South Africa ◽  
Life History ◽  
Early Life ◽  
Early Life History ◽  
Extensive Study ◽  
Western Boundary ◽  
Boundary Current ◽  
Pomatomus Saltatrix ◽  
Agulhas Current ◽  
Southward Transport

Several authors have stated that southward transport of the early life-history stages of Pomatomus saltatrix occurs by passive drift in the Agulhas Current, a strong western boundary current which flows southwards following the edge of the continental shelf of eastern South Africa. However, an extensive study of the ichthyoplankton occurring in shelf and Agulhas Current waters from 29�S to 34�S located P. saltatrix larvae only in the shelf waters off KwaZulu-Natal. Sampling of fish eggs in the inshore shelf waters 60 km south of Durban on a regular basis has confirmed spawning of P. saltatrix to occur in this region. The data thus suggest that larval dispersal might occur in shelf waters where, although strongly influenced by the Agulhas Current, southward transport is not as rapid.

Comparing Early Life History Strategies of Pomatomus saltatrix: a Global Approach

1996 ◽  
Vol 47 (2) ◽  
pp. 365 ◽  
Author(s):  
F Juanes ◽  
JA Hare ◽  
AG Miskiewicz
Keyword(s):  
Life History ◽  
Early Life ◽  
Life History Traits ◽  
Early Life History ◽  
Growth Patterns ◽  
Life History Strategies ◽  
Eastern Coast ◽  
The South ◽  
Pomatomus Saltatrix ◽  
South Eastern

Pomatomus saltatrix (Pisces:Pomatomidae) is a highly migratory, continental-shelf species with a worldwide subtropical distribution including the eastern coast of North America, the Gulf of Mexico, Mediterranean Sea, Black Sea, north-western Africa, the eastern coast of South America, the south-eastern coast of South Africa, and the south-eastern and south-westem coasts of Australia. This paper summarizes available life history information from the different regions where P. saltatrix occurs, with a focus on the early life history. The basic physical oceanography of these regions is also reviewed to elucidate patterns in larval transport. Comparison of these populations suggests that there are commonalties: adults migrate to spawning grounds; eggs and larvae are typically advected along-shore to juvenile nursery habitats; juveniles recruit to inshore habitats at a similar size, and there they grow rapidly and are mainly piscivorous, feeding primarily on atherinids and engraulids. There are also a number of life history traits that are quite variable among populations: the number of annual reproductive peaks, the number of juvenile cohorts, adult growth patterns and reproductive parameters. Comparison of these life history patterns leads to several non-exclusive hypotheses as to the adaptive significance of variations in life history traits. The goal is to identify areas where more research is needed to assess the degree to which populations of a global species are adapted to their local environment.

ILFC Symposium. Early Life History of Pomatomus saltatrix: Introduction

1996 ◽  
Vol 47 (2) ◽  
pp. 309
Author(s):  
AG Miskiewicz ◽  
F Juanes ◽  
JA Hare
Keyword(s):  
Life History ◽  
Early Life ◽  
Early Life History ◽  
Pomatomus Saltatrix ◽  
History Of

Prey tell: what quillback rockfish early life history traits reveal about their survival in encounters with juvenile coho salmon

2020 ◽  
Vol 650 ◽  
pp. 7-18 ◽  
Author(s):  
HW Fennie ◽  
S Sponaugle ◽  
EA Daly ◽  
RD Brodeur
Keyword(s):  
Life History ◽  
Early Life ◽  
Life History Traits ◽  
Direct Evidence ◽  
Coho Salmon ◽  
Larval Fish ◽  
Early Life History ◽  
In The Wild ◽  
Otolith Microstructure Analysis ◽  
Pelagic Juvenile

Predation is a major source of mortality in the early life stages of fishes and a driving force in shaping fish populations. Theoretical, modeling, and laboratory studies have generated hypotheses that larval fish size, age, growth rate, and development rate affect their susceptibility to predation. Empirical data on predator selection in the wild are challenging to obtain, and most selective mortality studies must repeatedly sample populations of survivors to indirectly examine survivorship. While valuable on a population scale, these approaches can obscure selection by particular predators. In May 2018, along the coast of Washington, USA, we simultaneously collected juvenile quillback rockfish Sebastes maliger from both the environment and the stomachs of juvenile coho salmon Oncorhynchus kisutch. We used otolith microstructure analysis to examine whether juvenile coho salmon were age-, size-, and/or growth-selective predators of juvenile quillback rockfish. Our results indicate that juvenile rockfish consumed by salmon were significantly smaller, slower growing at capture, and younger than surviving (unconsumed) juvenile rockfish, providing direct evidence that juvenile coho salmon are selective predators on juvenile quillback rockfish. These differences in early life history traits between consumed and surviving rockfish are related to timing of parturition and the environmental conditions larval rockfish experienced, suggesting that maternal effects may substantially influence survival at this stage. Our results demonstrate that variability in timing of parturition and sea surface temperature leads to tradeoffs in early life history traits between growth in the larval stage and survival when encountering predators in the pelagic juvenile stage.

scholarly journals Early life history responses and phenotypic shifts in a rare endemic plant responding to climate change

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Daniel E Winkler ◽  
Michelle Yu-Chan Lin ◽  
José Delgadillo ◽  
Kenneth J Chapin ◽  
Travis E Huxman
Keyword(s):  
Climate Change ◽  
Life History ◽  
Phenotypic Variation ◽  
Early Life ◽  
Early Life History ◽  
Interactive Effects ◽  
Endemic Plant ◽  
Cushion Plant ◽  
Rare Endemic

We studied how a rare, endemic alpine cushion plant responds to the interactive effects of warming and drought. Overall, we found that both drought and warming negatively influenced the species growth but that existing levels of phenotypic variation may be enough to at least temporarily buffer populations.

Characterizing the early life history of an imperiled freshwater mussel (Ptychobranchus jonesi) with host-fish determination and fecundity estimation

2017 ◽  
Vol 36 (2) ◽  
pp. 338-350 ◽  
Author(s):  
John M. McLeod ◽  
Howard L. Jelks ◽  
Sandra Pursifull ◽  
Nathan A. Johnson
Keyword(s):  
Life History ◽  
Early Life ◽  
Freshwater Mussel ◽  
Early Life History ◽  
Host Fish ◽  
History Of
Sign in / Sign up

Export Citation Format

Share Document