scholarly journals Planktonic Larval Duration, Settlement, and Growth Rates of the Young-of-the-Year of Two Sand Basses (Paralabrax nebulifer and P. maculatofasciatus: fam. Serranidae) from Southern California

2012 ◽  
Vol 111 (1) ◽  
pp. 15-21 ◽  
Author(s):  
Larry G. Allen ◽  
Heidi E. Block
Keyword(s):  
Growth Rates ◽  
Southern California ◽  
Larval Duration ◽  
Young Of The Year ◽  
Planktonic Larval Duration

scholarly journals Genetic Analysis of Larval Dispersal, Gene Flow, and Connectivity

2018 ◽  
Keyword(s):  
Larval Dispersal ◽  
Genetic Data ◽  
Larval Duration ◽  
Marine Systems ◽  
Marine Connectivity ◽  
Two Generations ◽  
Dispersal Distances ◽  
Long Timescales ◽  
The Relationship ◽  
Planktonic Larval Duration

Does the dispersal of planktonic larvae promote strong connections between marine populations? Here we describe some of the most commonly used population- and individual-based genetic methods that have enhanced our understanding of larval dispersal and marine connectivity. Both approaches have strengths and weaknesses. Choosing between them depends on whether researchers want to know about average effective rates of connectivity over long timescales (over hundreds to thousands of generations) or recent patterns of connectivity on shorter timescales (one to two generations). The use of both approaches has improved our understanding of larval dispersal distances, the relationship between realized dispersal (from genetics) and dispersal potential (from planktonic larval duration), and the crucial distinction between genetic and demographic connectivity. Although rarely used together, combining population- and individual-based inferences from genetic data will likely further enrich our understanding of the scope and scale of larval dispersal in marine systems.

scholarly journals Fish densities associated with structural elements of oil and gas platforms in southern California

2019 ◽  
Vol 95 (4) ◽  
pp. 639-656 ◽  
Author(s):  
Erin L Meyer-Gutbrod ◽  
Li Kui ◽  
Mary M Nishimoto ◽  
Milton S Love ◽  
Donna M Schroeder ◽  
...  
Keyword(s):  
Habitat Use ◽  
Southern California ◽  
Oil And Gas ◽  
Fish Assemblages ◽  
Fish Habitat ◽  
Artificial Reef ◽  
Offshore Structures ◽  
Structural Elements ◽  
Structural Element ◽  
Young Of The Year

There are thousands of offshore oil and gas platforms worldwide that will eventually become obsolete, and one popular decommissioning alternative is the "rigs to reefs" conversion that designates all or a portion of the underwater infrastructure as an artificial reef, thereby reducing the burden of infrastructure removal. The unique architecture of each platform may influence the size and structure of the associated fish assemblage if different structural elements form distinct habitats for fishes. Using scuba survey data from 11 southern California platforms from 1995 to 2000, we examined fish assemblages associated with structural elements of the structure, including the major horizontal crossbeams outside of the jacket, vertical jacket legs, and horizontal crossbeams that span the jacket interior. Patterns of habitat association were examined among three depth zones: shallow (<16.8 m), midwater (16.8–26 m), and deep (>26 m); and between two life stages: young- of-the-year and non-young-of-the-year. Fish densities tended to be greatest along horizontal beams spanning the jacket interior, relative to either horizontal or vertical beams along the jacket exterior, indicating that the position of the habitat within the overall structure is an important characteristic affecting fish habitat use. Fish densities were also higher in transects centered directly over a vertical or horizontal beam relative to transects that did not contain a structural element. These results contribute to the understanding of fish habitat use on existing artificial reefs, and can inform platform decommissioning decisions as well as the design of new offshore structures intended to increase fish production.

Variation in the growth of larval and juvenile snapper, Chrysophrys auratus (Sparidae)

2012 ◽  
Vol 63 (12) ◽  
pp. 1231 ◽  
Author(s):  
Carina J. Sim-Smith ◽  
Andrew G. Jeffs ◽  
Craig A. Radford
Keyword(s):  
Growth Rates ◽  
Early Growth ◽  
Pelagic Larval Duration ◽  
Growth Trajectories ◽  
Larval Duration ◽  
Juvenile Period ◽  
Otolith Increments ◽  
Commercially Important ◽  
Size At Age ◽  
Early Juvenile Period

For many fish species, growth and mortality of larvae are closely coupled, with faster-growing larvae generally experiencing higher survivorship in the plankton, which may lead to higher recruitment. Using back-calculated growth trajectories derived from otolith increments we used the modified Fry model to estimate the growth rate of larvae and early juveniles of the commercially important sparid, Chrysophrys auratus, at four sites around northern New Zealand. Back-calculated growth rates were used to test the hypothesis that fish with a short pelagic larval duration (≤20 days) grew faster than did fish with a long pelagic larval duration (>24 days) during both the larval and juvenile periods. At three of the four sites, fish with a short larval duration grew significantly faster during the larval period, and these larvae generally continued to have a larger size-at-age as juveniles up to 70-day-old. Growth rates for both the larval and early juvenile period were also found to vary significantly among the four sites and were found to be unrelated to differences in water temperature. Localised variation in early growth of C. auratus among sites may be important in helping explain differences in their contribution to the recruitment to C. auratus populations.

Fitness consequences of habitat use for juvenile cutthroat trout: energetic costs and benefits in pools and riffles

2001 ◽  
Vol 58 (3) ◽  
pp. 585-593 ◽  
Author(s):  
Jordan S Rosenfeld ◽  
Shelly Boss
Keyword(s):  
Growth Rates ◽  
Habitat Preference ◽  
Cost Benefit Analysis ◽  
Cutthroat Trout ◽  
Cost Benefit ◽  
Invertebrate Drift ◽  
Oncorhynchus Clarki ◽  
Fitness Consequences ◽  
Young Of The Year ◽  
Bioenergetic Cost

To assess freshwater habitat requirements of juvenile anadromous cutthroat trout, Oncorhynchus clarki, we measured habitat preference and growth rates of young-of-the-year (YOY) and 1- to 2-year-old fish confined to either pools or riffles in Husdon Creek, British Columbia, during 1999. YOY preferred pools to riffles in habitat-preference experiments, despite normally occurring at lower densities in pools. YOY grew in both pools and riffles when experimentally confined to either habitat, but growth rates were higher in pools. Larger juvenile cutthroat trout, on average, grew in pools, but consistently lost weight in riffles, indicating that pools are a habitat preference for YOY but a requirement for larger fish. A bioenergetic cost–benefit analysis (based on swimming costs and energy intake from invertebrate drift) indicates that energetics alone are sufficient to account for avoidance of riffles by larger cutthroat trout, without having to invoke greater predation risk in shallow habitats. Energetics modeling demonstrates that the smaller size and energetic needs of YOY allow exploitation of habitats (e.g., pocket pools in riffles) that are unavailable to larger fish.

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