Aspects of Reproductive Biology of the Scalloped Hammerhead Shark, Sphyrna Lewini, off Northeastern Brazil

@article{Hazin2004AspectsOR,
  title={Aspects of Reproductive Biology of the Scalloped Hammerhead Shark, Sphyrna Lewini, off Northeastern Brazil},
  author={Fabio Hissa Vieira Hazin and Alessandra F. Fischer and Matt K. Broadhurst},
  journal={Environmental Biology of Fishes},
  year={2004},
  volume={61},
  pages={151-159}
}
Ninety four scalloped hammerhead sharks, Sphyrna lewini (53 females and 41 males) ranging in size from 121 to 321 cm total length (TL), were collected from surface gillnetters operating off northeastern Brazil and throughout the southwestern equatorial Atlantic Ocean between January and December 1996. A common regression for TL and eviscerated weight (EW) was calculated as, log EW = −11.786 + 2.889 log TL. Females and males were categorised into reproductive stages (4 and 2, respectively… 

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SIZE DISTRIBUTION AND SEX RATIO OF SCALLOPED HAMMERHEAD SHARKS ( Sphyrna lewini ) IN INDIAN OCEAN AT SOUTHERN PART OF JAVA AND NUSA TENGGARA, INDONESIA

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The life histories of two globally endangered hammerhead sharks were examined using samples collected from a range of commercial fisheries operating along the east coast of Australia, finding no significant difference in length and age at maturity of male and female S. mokarran.
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References

SHOWING 1-10 OF 17 REFERENCES

Age, growth and reproductive biology of the silky shark, Carcharhinus falciformis, and the scalloped hammerhead, Sphyrna lewini, from the northwestern Gulf of Mexico

SynopsisThe silky shark, Carcharhinus falciformis, and scalloped hammerhead, Sphyrna lewini, represent >80% of the shark by-catch of the winter swordfish/tuna longline fishery of the northwestern

Biology of three hammerhead sharks (Eusphyra blochii, Sphyrna mokarran and S. lewini) from Northern Australia

The hammerhead sharks Eusphyra blochii, Sphyrna mokarran and S. lewini form part of the incidental catch of a commercial gill-net fishery off northern Australia and it is suggested that these occur offshore of the study area.

Maturation of the night shark, Carcharhinus signatus, in the Southwestern Equatorial Atlantic Ocean

A seasonal peak in male GSI during spring, combined with evidence of female ovulation shortly after suggests that copulation occurs in summer, and analysis of various morphometric relationships showed significant differences between males and females for regressions of precaudal length and interdorsal space.

The determinants of sexual segregation in the scalloped hammerhead shark,Sphyrna lewini

  • A. Klimley
  • Environmental Science, Biology
    Environmental Biology of Fishes
  • 2004
It is suggested that female segregation increases fitness, resulting in more rapid growth for the former sex, matching the female reproductive lifetime to that of males.

The storage of spermatozoa in the oviducal glands of western North Atlantic sharks

  • H. L. Pratt
  • Environmental Science
    Environmental Biology of Fishes
  • 2004
Spermatozoa stored in oviducal glands of sharks sampled off the North American east coast were revealed by viewing stained tissue sections using light microscopy and three insemination patterns are proposed to account for differences.

Review of a small-scale pelagic longline fishery off northeastern Brazil

The annual catches of four small longliners operating off northeast Brazil from 1983 to 1997 were examined across different areas and locations. The total catch comprised tunas (30%), sharks (54%),

The shark nursery of Bulls Bay, South Carolina, with a review of the shark nurseries of the southeastern coast of the United States

  • J. Castro
  • Environmental Science
    Environmental Biology of Fishes
  • 2004
SynopsisShark nurseries, or nursery areas, are geographically discrete parts of a species range where the gravid females of most species of coastal sharks deliver their young or deposit their eggs,

Record of four pregnant females of the scalloped hammerhead, Sphyrna lewini (Sphyrnidae) in Senegalese waters

Les auteurs rapportent la capture de quatre femelles gestantes de Sphyrna lewini (Sphyrnidae) dans la region marine de Dakar-Ouakam (Senegal, Atlantique tropical oriental) et decrivent leurs contenus

Biological observations on Sphyrna lewini and S. tudes (Chondrichthyes, Sphyrnidae) from Northern Brazil

La longueur totale, the taille and le nombre d'embryons sont plus importants que dans les autres regions, on observe une organisation semblable des communautes.