Fertilization efficiency in free-spawning invertebrates in the marine environment depends on the complex interaction between biological and physical factors. Experimental evidence indicates that in some taxa, a considerable amount of fertilization may take place on the substrate and within flow structures in close proximity to a spawning female. Gametes can be retained on a spawning animal, res...

We used 320 young-of-the-year (YOY) specimens of the highly migratory and overfished Atlantic bluefin tuna, Thunnus thynnus, Linnaeus 1758, to evaluate the hypothesis that Atlantic bluefin tuna comprises 2 stocks with spawning grounds in the Gulf of Mexico and in the Mediterranean Sea. Significant genetic differentiation at 8 nuclear microsatellite loci (F(ST) = 0.0059, P = 0.0005) and at the m...

This study was investigated spawning behavior, structure of egg masses and egg development in Aplysia kurodai inhabiting the coastal waters of Jeju Island, Korea. The mating and courtship behavior of A. kurodai occurred in the form of unilateral copulating with chain formation. In chain copulation, only the first animal acted as a female; the second and succeeding animals acted as males (sperm ...

The reproductive biology of albacore tuna, Thunnus alalunga, in the western Indian Ocean was examined through analysis of the sex ratio, spawning season, length-at-maturity (L50), spawning frequency and fecundity. From 2013 to 2015, a total of 923 female and 867 male albacore were sampled. A bias in sex ratio was found in favor of females with fork length (LF) < 100 cm. Using histological analy...

The way organisms allocate their resources to growth and reproduction are key attributes differentiating life histories. Many organisms spawn multiple times in a breeding season, but few studies have investigated the impact of serial spawning on reproductive allocation. This study investigated whether resource allocation was influenced by parental characteristics and prior spawning history in a...

The physical habitat used during spawning may potentially be an important factor affecting reproductive output of broadcast spawning marine fishes, particularly for species with complex, substrate-oriented mating systems and behaviors, such as Atlantic cod Gadus morhua. We characterized the habitat use and behavior of spawning Atlantic cod at two locations off the coast of southwestern Iceland ...

a total of 48 female spirlins alburnoides sp. from the kesselian stream (south caspian sea basin, northern iran) were examined during a period from july 2008 to june 2009 to obtain data on fecundity, and to determine the spawning season of this carp. the mean absolute fecundity of females spirlin was 1722.92 (653.88) eggs. the fecundity has positive correlation with the size of the female. the...

Population genetic compositions of the three largest spawning groups of Lake Erie walleyes Sander vitreus (Maumee River, Sandusky River, and Van Buren Bay reefs) were tested for temporal and spatial consistency across 14 years using nine nuclear DNA microsatellite loci from 726 adult walleyes collected in 1995, 1998, 2003, 2007, and 2008. Previous genetic work focused on a one-time “snapshot”; ...

background: fluoxetine (prozactm) is one of the most popular antidepressant that can be released to aquatic systems via sewage-treatment effluents. it is suspected to provoke substantial effects in the aquatic environment. methods: in spawning tanks, specimens were exposed to concentrations of 0 and 0.54 µgl-1 fluoxetine from male introduction until the larvae had hatched. prior to spawning, ne...

Movement of nutrients across ecosystem boundaries can have important effects on food webs and population dynamics. An example from the North Pacific Rim is the connection between productive marine ecosystems and freshwaters driven by annual spawning migrations of Pacific salmon (Oncorhynchus spp). While a growing body of research has highlighted the importance of both pulsed nutrient subsidies ...