Juvenile White Shark High Resolution Tracking

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DISCOVERY Yacht Valkyrie
Carpinteria Beach, California
September 23 - 24, 2023

Research Team

  • Chris Lowe (Director, PhD)
  • Ryan Logan (Post Doc, PhD)
  • Patrick Rex (Research Tech, M.S.)
  • Zach Merson (Graduate Student)
  • Elizabeth Jahn (Graduate Student)
  • Whitney Jones (Graduate Student)
  • Lauren Faulkner (Graduate Student)
  • Kelsey Lowe (Education Coordinator)

Project Overview

The purpose of this research project has been to study a group of juvenile white sharks which have made Carpinteria Beach their home and nursery.

Duration of Project

This project will consist of three expeditions, spaced a month apart in August, September, and October.

Expedition Summary

In September of 2023, The International SeaKeepers Society has again partnered with the California State University Long Beach Shark Lab to investigate further into the juvenile white sharks inhabiting a stretch of beach in Carpinteria, CA. DISCOVERY Yacht owner, Tom Petersen once again hosted the team, acting as captain and chef for the days spent offshore aboard DISCOVERY Yacht Valkyrie.

Over the course of two and a half days at sea, the team encountered a number of juvenile white sharks. The goal was to catch, restrain, and tag a juvenile white shark with a high-resolution accelerometer tag package that includes a video camera to see POV what the shark sees, and then actively track that individual for up to 48 hours until the tag package comes off the shark and can be collected. Other research methods included tagging prey species such as bat rays and leopard sharks in order to determine if the movements of prey also affect the movements of the sharks in the area.

To this end, the team attempted the strike net technique a number of times to catch and restrain the sharks they encountered. Unfortunately, the team was unsuccessful as these particular sharks were a bit bigger than what is feasible and were otherwise adept at escaping the net. To put it into perspective, as the shark is swimming along the coast, a large gill net is deployed about 100 yards in front of it from the bow of a 17' skiff, with the hope that the shark will become engulfed by the net, so that a second skiff can come and pull the far end of the net backwards. Seconds later, the shark would be placed in an underwater sling between the two boats. While this is a very humane and effective method for restraining a white shark, in an area so close to shore and beach goers, it can be rather difficult at times. However, a second method of tagging white sharks is with a pole spear from the skiff without needing to retrain the shark, when the animal swims close to the surface. Using this method, the team was successful in tagging two white sharks. In addition, they accomplished their goal of using BRUVs or Baited Remote Underwater Video, to observe and record the biodiversity in the area. With that, they were able to capture footage of white sharks, leopard sharks, bat rays, and several other fish species that inhabit the area. As usual, the team was very happy to be back aboard DISCOVERY Yacht Valkyrie with Captain Tom Petersen as their host.

Application

This research can be used in the future to understand why sharks, at different life stages may aggregate in certain areas. They may be choosing to be close to shore to follow their prey with less competition, and/or to avoid being preyed upon by larger sharks. In terms of environmental parameters such as warmer temperatures, this too can be an indicator of why the juvenile white sharks choose certain beaches. Answering all these questions can help inform, and predict future aggregation sites. This in turn can be used to bring awareness and education to the public about who they are sharing the waves with, how best to share the space, and maybe curb some of the fear associated with white sharks, and sharks in general.

Location

Carpinteria Beach, California

Video