Before great white sharks migrate north to Cape Cod for the summer and fall, shark researchers are trying to figure out where and when the apex predators mate.
Right now in early April, many of the East Coast great whites are off the North Carolina coast, and scientists from the nonprofit OCEARCH will be heading to the region soon to collect data from sharks.
The researchers hope to sample mature white sharks to solve the most elusive piece of the Western North Atlantic white shark puzzle: when and where they breed.
“Our comprehensive studies of the white shark, the ocean’s top predator, are in their final stages in the Western North Atlantic, and now we turn our attention to a gap that still remains,” said OCEARCH Chief Scientist Bob Hueter. “This is the great migration of sharks from their overwintering grounds off the southeast U.S. towards their summer feeding areas, as increasing spring temperatures and light levels signal to the sharks that it’s time to move.
“Before they go, we seek to study the sharks’ condition after their winter south, and in particular, the reproductive state of the adult sharks,” Hueter added.
The science team will collect blood samples from the mature sharks off North Carolina, which will be used to measure hormone levels. Also, ultrasound technology will be used to scan mature females and evaluate their reproductive status.
The researchers hope to assess the presence of seminal fluid and sperm in males, and mating wounds on females.
“Seeing the adults off the Outer Banks region is challenging, as they are spread out and ocean conditions can be rough, but we need data and samples from this part of the population to put the last pieces of the Western North Atlantic white shark puzzle into places,” Hueter said.
Other important studies include assessing what these sharks are eating when they’re down south, what contaminants they encounter there, and how they deal with various challenges to their health and survival.
OCEARCH will also apply tags to the white sharks they study and release, allowing the team and the public alike to track the animals for years to come.
OCEARCH’s Western North Atlantic White Shark Study includes a full health assessment of each shark, microbiological studies, movement, temperature and depth studies through the use of three different tags, and more.
With 88 sharks already studied in the Western North Atlantic, OCEARCH is in the last stages of their sample collection in this region. The team has just 12 sharks left to reach their goal of 100 sharks sampled and tagged in the Western North Atlantic.
