As a highly vulnerable marine animal, conservation efforts are key to protect a range of shark species. However, gathering information about breeding habits, which could help with these efforts, is challenging.
A team of researchers at the School of Mathematical and Natural Sciences at Arizona State University have developed a new “birth-alert-tag” (BAT) device, the first of its kind, that can be implanted in a pregnant shark to help monitor the precise time and location of shark births. The new device is described in a recent article published in Science Advances.
The device itself looks like a small egg that’s implanted into the uterus of a pregnant shark. Then, when the shark gives birth, the device comes out as well. In so doing, it sends researchers a trove of important data, such as when and where the birth took place. The study published in Science Advances showed on two different pregnant sharks that the device was effective and safe to use. The devices egg shape allows for easy implantation in the uterus without disrupting the existing embryos.
This approach to monitoring shark pregnancy and birth rates is not inherently new. A similar approach, using similar technology, has been used in the past for other land animals to track their births. A key challenge that researchers have long faced was designing something uniquely suited to a marine environment. While various tagging and tracking methods have been implemented in marine environments, tracking birth rates has remained a challenge. Thanks to new technology, this barrier has been overcome.
In the study, researchers followed 22 female whale sharks, though initial blood tests and ultrasounds did not show they were pregnant. They can now follow these sharks to study their mating and birthing patterns.
The team also followed a tiger shark and a scalloped hammerhead that were pregnant and that had the device implanted. The team was able to precisely locate where both sharks gave birth. The team hopes that better studying shark birthing habits could help prevent human activities from interfering in these natural processes.
Sources: Mongabay; Sciences Advances
