A Comparison of Reproductive and Energetic States in a Marine Apex Predator (the Tiger Shark, Galeocerdo cuvier) | Semantic Scholar (2024)

The findings suggest that nurse and blacktip sharks differ in their energetic strategy to support reproduction, however, they likely rely on physiologically important fatty acids during mating, to support spermatogenesis.

A physiological impairment caused by bile accumulation in juvenile tiger sharks, possibly due to prolonged fasting is reported, suggesting that, even though sharks have adaptations that prevent them from dying from starvation, alarming physiological alterations might occur.

This study collected finetooth sharks from the northern Gulf of Mexico with a potential disparity in periodicity within North American waters to better define regional variability, and results will be impactful, because regionally distinct reproductive parameters can now be considered for future assessments.

This study provides a baseline assessment of body condition and internal physiological state for a data-poor marine species and demonstrates significant ontogenetic, sexual, and seasonal variation in G. cirratum energetic state.

The first evidence of mating scars in female tiger sharks Galeocerdo cuvier at the Fernando de Noronha Archipelago (FEN) is reported, indicating the importance of FEN for tiger shark reproduction in western equatorial Atlantic waters.

A conceptual model of expected changes in nutritional and trophic markers across life stages of female tiger sharks is proposed.

The energetic consequences of variable prey resource use in a widely distributed marine carnivore, juvenile sand tiger sharks (Carcharias taurus), are examined to underscore how intraspecific variation in resource use may impact the energy metabolism of animals.

Findings from this study provide important information on movement of this species in the GOM and highlight their restricted use of continental shelf habitat and resident behavior that will need to be incorporated in future stock assessments and extinction risk analyses.

It is hypothesize that mating could occur in the eastern Bahamas as early as May, but is probably concentrated in midsummer (i.e. July), and that Columbus Point, Cat Island, may be a mating habitat for the oceanic whitetip shark.

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The results suggest that Tiger Beach may function as a refuge habitat, allowing females to reach maturity free from male mating harassment, as well as functioning as a gestation ground where gravid females can benefit from year-round calm warm waters, which may reduce the gestation period and accelerate embryo development.

The data suggest that female tiger sharks in Hawaii give birth only once every three years, which could have major implications for conservation and management of this species, as it suggests that tiger shark fecundity is 33% lower than previously thought.

Energy reserves invested in reproduction by poor-condition females increase their risk of mortality, and laboratory experiments revealed that female cod with high prespawning condition factors ended reproduction in better condition than females with low prespwned condition factors.

It is concluded that sifaka follow the “classic” reproductive strategy, which mated during the periods of high and declining food availability, gave birth during the lean season, and then timed mid/late lactation with the period of increasing food availability.

It is suggested that the female reproductive cycle is biennial, similar to those from other populations, although size-at-maturity of males was slightly different from South African and Australian populations.

A detailed ‘case history’ of nurse shark reproductive behavior is presented that may be used as a template for future work on Shark reproductive behavior of other species.

Heterogeneity in ovulatory cycles suggests that the endocrine system evolved a transmutable system for regulating steroidogenesis and the control of the reproductive events in female elasmobranchs.

The authors demonstrate that clear liquid in the tiger shark egg case is an energy-rich embryotrophe that nourishes the embryos to large size.

Overall body dimensions, small sharks are roughly geometrically similar to large sharks, at least within the species the authors examined, and juvenile tiger (and to a lesser extent bull sharks) are notable in having proportionately larger caudal fins compared to adult sharks.

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