Shark, Skate, and Ray Life History
Shark, Skate, and Ray Life History
Elasmobranchs (sharks, skates and rays) are slow growing, long lived, reach sexual maturity at a late age and reproduce few young. These life history characteristics make this group of fish very susceptible to human induced impacts (overfishing) and environmental impact (i.e. climate change). Age information forms the basis for the calculations of growth rate, mortality rate and productivity, making it one of the most influential variables for estimating a population’s status and assessing the risks associated with both human and environmental impacts. Collaborating with colleagues from University of Southern Mississippi’s Gulf Coast Research lab and NOAA Fisheries, Dr. Sulikowski and his team are currently studying several species of sharks and sturgeon within the Gulf of Mexico in order to update this important life history characteristic. They are also collaborating with colleagues from Pelagios Kakunja in the Sea of Cortez, Canada’s Department of Fisheries and Oceans (Gulf Fisheries Center in Moncton, NB and the Northwest Atlantic Fisheries Center in St. John’s, NL), and Firat University (Elazig, Turkey) to further investigate elasmobranchs in international waters.
Elasmobranchs (sharks, skates and rays) are slow growing, long lived, reach sexual maturity at a late age and reproduce few young. These life history characteristics make this group of fish very susceptible to human induced impacts (overfishing) and environmental impact (i.e. climate change). Age information forms the basis for the calculations of growth rate, mortality rate and productivity, making it one of the most influential variables for estimating a population’s status and assessing the risks associated with both human and environmental impacts. Collaborating with colleagues from University of Southern Mississippi’s Gulf Coast Research lab and NOAA Fisheries, Dr. Sulikowski and his team are currently studying several species of sharks and sturgeon within the Gulf of Mexico in order to update this important life history characteristic. They are also collaborating with colleagues from Pelagios Kakunja in the Sea of Cortez, Canada’s Department of Fisheries and Oceans (Gulf Fisheries Center in Moncton, NB and the Northwest Atlantic Fisheries Center in St. John’s, NL), and Firat University (Elazig, Turkey) to further investigate elasmobranchs in international waters.
Reproduction is another important life history trait that must be fully understood if successful management of elasmobranchs is to occur. A large portion of the lab’s work is focused on developing non-lethal techniques or protocols for the study of this life history characteristic. Researchers can take a blood or muscle sample and analyze it for reproductive hormones that are present within the shark or ray. In addition, we use a portable ultrasound (see video!) to take images and video of growing shark babies within the mother. In collaboration with Dr. Neil Hammershlag of the University of Miami’s Rosenstiel School of Marine & Atmospheric Science, James and his team are using these techniques to track the reproductive cycle and length of gestation of tiger sharks in the Bahamas and several species of sharks along the coast of south Florida. Working with Dr. Greg Skomal, Dr. James Ketchum and Mauricio Hoyas this work is also being conducted on White sharks in several locations in North America.
Reproduction is another important life history trait that must be fully understood if successful management of elasmobranchs is to occur. A large portion of the lab’s work is focused on developing non-lethal techniques or protocols for the study of this life history characteristic. Researchers can take a blood or muscle sample and analyze it for reproductive hormones that are present within the shark or ray. In addition, we use a portable ultrasound (see video!) to take images and video of growing shark babies within the mother. In collaboration with Dr. Neil Hammershlag of the University of Miami’s Rosenstiel School of Marine & Atmospheric Science, James and his team are using these techniques to track the reproductive cycle and length of gestation of tiger sharks in the Bahamas and several species of sharks along the coast of south Florida. Working with Dr. Greg Skomal, Dr. James Ketchum and Mauricio Hoyas this work is also being conducted on White sharks in several locations in North America.