نتایج جستجو برای: spawning induction

تعداد نتایج: 204295  

2015
Alvin Chelliah Halimi Bin Amar Julian Hyde Katie Yewdall Peter D. Steinberg James R. Guest

Knowledge about the timing and synchrony of coral spawning has important implications for both the ecology and management of coral reef ecosystems. Data on the timing of spawning and extent of synchrony, however, are still lacking for many coral reefs, particularly from equatorial regions and from locations within the coral triangle. Here we present the first documentation of a multi-species co...

2015
Anders Frugård Opdal Christian Jørgensen

Harvesting may be a potent driver of demographic change and contemporary evolution, which both may have great impacts on animal populations. Research has focused on changes in phenotypic traits that are easily quantifiable and for which time series exist, such as size, age, sex, or gonad size, whereas potential changes in behavioural traits have been under-studied. Here, we analyse potential dr...

Journal: :Journal of fish biology 2010
W J Bubley O Pashuk

Sand perch Diplectrum formosum were collected in the Atlantic Ocean waters off the south-eastern U.S. for life history analyses between April 2001 and July 2004 and ranged in size from 63 to 236 mm standard length (L(S)) and 0-8 years of age. Diplectrum formosum are simultaneous hermaphrodites that reach 50% sexual maturity at 12.2 months and 122.8 mm L(S) for testicular tissue and 13.6 months ...

Journal: :General and comparative endocrinology 2011
Fernanda Ferreira Loureiro de Almeida Eva Andersson Christian Mittelholzer Orjan Karlsen Geir Lasse Taranger Rüdiger W Schulz

Pituitary mRNA levels of gonadotropin β-subunits and of their cognate receptors in the testis were studied during puberty in Atlantic cod under normal and experimental photoperiod conditions that suppressed, delayed or accelerated testis maturation. Results are discussed in context with changes in testicular histology and plasma androgen levels, considered as end points of gonadotropic regulati...

2016
Dorte Bekkevold Riho Gross Timo Arula Sarah J. Helyar Henn Ojaveer

Herring, Clupea harengus, is one of the ecologically and commercially most important species in European northern seas, where two distinct ecotypes have been described based on spawning time; spring and autumn. To date, it is unknown if these spring and autumn spawning herring constitute genetically distinct units. We assessed levels of genetic divergence between spring and autumn spawning herr...

2013
Ryan R. E. Stanley Brad deYoung Paul V. R. Snelgrove Robert S. Gregory

To understand coastal dispersal dynamics of Atlantic cod (Gadus morhua), we examined spatiotemporal egg and larval abundance patterns in coastal Newfoundland. In recent decades, Smith Sound, Trinity Bay has supported the largest known overwintering spawning aggregation of Atlantic cod in the region. We estimated spawning and dispersal characteristics for the Smith Sound-Trinity Bay system by fi...

2005
E. A. WHITEMAN C. A. JENNINGS R. S. NEMETH

Ultrasonic imaging was used to determine the spawning population structure and develop a fecundity estimation model for a red hind Epinephelus guttatus spawning aggregation within the Red Hind Bank Marine Conservation District, St Thomas, U.S.V.I. The spawning population showed considerable within-month and between-month variation in population sizeand sex-structure. In the spawning season stud...

2013
Florence I. M. Thomas Louise T. Kregting Brian D. Badgley Megan J. Donahue Philip O. Yund

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...

Journal: :The Journal of heredity 2007
Jens Carlsson Jan R McDowell Jeanette E L Carlsson John E Graves

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...

2014
Chi-Hoon Lee Bong-Kiun Kaang Young-Don Lee

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 ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید