Non-linear genetic isolation by distance: implications for dispersal estimation in anadromous and marine fish populations

Recruitment variability is commonly associated with fluctuations in abundance of marine fish populations. Previous studies have focussed on stock-specific correlative or mechanistic models or on comparisons of recruitment variations of several stocks or species. The purpose of this study is to determine whether recruitment variability of commercial marine fish populations is associated with either size or the duration of early life history stages. The analysis was performed with data from 86 stocks representing 21 species of commercial marine fish. Univariate analysis shows that neither egg size nor the length at hatch is significantly correlated with recruitment variability. The change in length during the larval phase, which is representative of the duration of the stage, is significantly positively correlated with recruitment variability. Multivariate analysis shows that recruitment variability increases with increasing length at metamorphosis but that recruitment variability is poorly associated with length at hatch. The degree of serial correlation is related to the relative duration of egg and larval stages. The results clearly indicate that recruitment variability is linked to characteristics of early life history stages.

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Feeding Schedule and Daily Food Consumption in Red-Throated Loons (Gavia stellata) over the Prefledging Period

The Auk ◽

10.1093/auk/101.3.593 ◽

1984 ◽

Vol 101 (3) ◽

pp. 593-599 ◽

Cited By ~ 17

Author(s):

T. E. Reimchen ◽

Sheila Douglas

Keyword(s):

British Columbia ◽

Food Consumption ◽

Marine Fish ◽

Average Duration ◽

Fish Populations ◽

Feeding Schedule ◽

Parental Feeding ◽

Daily Food ◽

Feeding Activities ◽

Coastal British Columbia

Abstract We describe parental feeding activities of Red-throated Loons (Gavia stellata) throughout the prefledging period at two freshwater nesting territories in coastal British Columbia. The nesting lake contained resident fish populations, but adult loons fed marine fish to their young, making an average of 11 flights per day (average duration 60 min per flight) to the ocean and returning each time with a single fish. Small shallow-bodied fish (Ammodytidae, Pholidae), which were easily swallowed by chicks, predominated in the diet during the 3 days following hatching. The total weight of fish fed to the chicks per day (8-194 g) increased over the prefledging period: adults returned fewer but larger fish (Embiotocidae) as the chick aged. Of the fish offered, 4% were too large for the chick to swallow.

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Recruitment in Marine Fish Populations

Fish Reproductive Biology ◽

10.1002/9781444312133.ch1 ◽

2009 ◽

pp. 9-47 ◽

Cited By ~ 3

Author(s):

Michael J. Fogarty ◽

Loretta O'Brien

Keyword(s):

Marine Fish ◽

Fish Populations

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Molecular Identification and Characterization of Vibrio Species and Mycobacterium Species in Wild and Cultured Marine Fish from the Eastern Mediterranean Sea

Microorganisms ◽

10.3390/microorganisms8060863 ◽

2020 ◽

Vol 8 (6) ◽

pp. 863 ◽

Cited By ~ 2

Author(s):

Yael Regev ◽

Nadav Davidovich ◽

Ran Berzak ◽

Stanley C. K. Lau ◽

Aviad P. Scheinin ◽

...

Keyword(s):

Mediterranean Sea ◽

Marine Fish ◽

Eastern Mediterranean ◽

Vibrio Species ◽

Wild Fish ◽

Fish Populations ◽

Pathogenic Microorganisms ◽

Mycobacterium Species ◽

Eastern Mediterranean Sea ◽

Significant Difference

In contrast to numerous documented pathogens and infectious diseases of aquaculture, there is a lack of baseline data and information regarding pathogenic agents’ prevalence in wild marine fish populations. This study focused on two common fish pathogenic microorganisms, namely Mycobacterium species and Vibrio species, both of which are known to be major causes of fish loss, occasionally to the extent of being a limiting factor in fish production. Both microorganisms are known as zoonotic agents. In total, 210 wild marine indigenous and Lessepsian fish from four different species from the eastern Mediterranean Sea were sampled and tested for Vibrio species and Mycobacterium species during a two-year period (2016–2017). Using PCR with 16S rRNA primers, we detected different strain variations of Mycobacterium species and Vibrio species and, based on the sequencing results, the overall prevalence for Vibrio species in wild fish in 2016 was significantly higher compared to 2017. No significant difference was detected for Mycobacterium species prevalence in wild fish between 2016 and 2017. In addition, 72 gilthead seabream (Sparus aurata) from an Israeli offshore marine farm were also examined during the two-year period (2017–2018). The results suggest that Mycobacterium species prevalence was significantly higher in 2018, while in 2017 there was no positive results for Mycobacterium species. In addition, there was no significant difference between both years in regard to the prevalence of Vibrio species for maricultured fish. These results highlight the necessity of continuous molecular monitoring in order to evaluate the prevalence of pathogenic microorganisms in both wild and cultured fish populations.

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