Zusammenfassung der Ressource
Natality vs Mortality of
Great White Sharks
- Natality
- Hard to determine due to the Inaccessibility of the specie
- Sexual maturity
- Juvenile
- Subadult
- Adult
- Aplacental vivipary
- They are not embryophagus
- Mating probably occurs between spring-
summer
- Gestation period unknown
- Life time: 70 years in average
- Mortality
- Shark attacks on humans
- GIll netting program (South Africa)
- 40 km of nets, 1354 sharks catched per year (in average)
- 39 white sharks
- Fishing = overexploitation
- Serious decline in shark population seen since 1992
- Commercial fishing
- Provoked and un provoked attacks
- Reputation
- Great White Sharks: The Biology of Charcharodon Charcharias
- Main objectives of the book
- -Improve the reputation of the Sharks
- Make Five Expeditions
- Tag as Many White Sharks as Possible
- Provide a long term assesment of population dynamics
- Protect the species
- Create Laws that prohibit
shark fishing in south
california, south australia
and south africa and create
conservation programs
world wide
- show a Full detail of the Great
white shark Biology
- Main results a conclusions from the book
- Results
- Shak biology and behavior studied
- 73-94 Sharks tagged
- Recorded interactions of humans
and sharks, fishing, tagging attacks
etc...
- successful efort to protect white
shark in californian and south
african waters
- Main conlusions
- Fishing mortality was
assumed to be constant
- Rarity of species
- Great white Sharks are an endangerde
species, Status: Vulnerable
- Myths still preveal
- Key organism for ecological balance
- Chapters Used ( the Chapters are
cientific papers with an unique theme
about Great white sharks
- Chapter 13: Reproduction in the male White shark ( Pag 131)
- Chapter 14: Pregnant white sharks and full-term embryos from japan (Pag 139)
- Chapter 15: Observations on a pregnant white shark with a review of reproductive biology (Pag 157)
- Chapter 36: First estimates of mortality and population size on the south african coast ( Pag 393)
- Chapter 37 : Population Dynamics of white sharks in spencer gulf, South australia (Pag 401)
- Chapter 45: More rare than dangerous: a case study of white shark conservation in california (Pag 481)
- General Methods from the book and it´s
papers
- methodology of Clark and Von
Schmidt, And Pratt
- Lateral or ventral incision
- tagging, shark capture, nets
- Petersen estimate
- Baranov catch equation
- population size determined by Petersen estimate