Mother Lemon Sharks Remember Birthplace After More Than a Decade
Sharks are some of nature's most spectacular creatures--and lemon sharks are no exception. Scientists have discovered that after 15 years, these animals return to their birthplace to give birth to their own young. The findings confirm this behavior for the first time ever in sharks.
Sharks are difficult to track as they make their way through the ocean. That's why the scientists tagged more than 2,000 baby sharks in the Bahamas over the 19-year ongoing project. This allowed them to monitor the sharks' ages and their movements over the course of their lifespan.
"We found that newborn sharks captured in the mid-1990s left the safety of the islands when they were between five and eight years old," said Kevin Feldheim, one of the researchers, in a news release. "Yet, despite leaving and visiting many other islands in their travels, these sharks 'remember' where they were born after a decade of roving, and are able to find the island again when they are pregnant and ready to give birth."
While scientists have long speculated that female sharks have the ability to return to their birthplace in order to give birth, they haven't been able to prove it--until now. The researchers were partly successful due to the geography that they had to work with, which allowed them to capture and tag so many sharks.
"The lagoon in Bimini is almost like a lake," said Samuel Gruber, one of the researchers, in a news release. "I realized that we had a chance to capture nearly every shark born into the lagoon each year, and this gave us the unique opportunity to see if the females actually came back to give birth. However it took us nearly two decades and countless hours in the field and laboratory, but we finally answered this long-standing question and many others with this paper."
Learning more about sharks and their habits is more important than ever as species numbers continue to decline. Shark finning has devastated populations and climate change is also impacting them. Now, scientists are taking an active role in their recovery, which could increase numbers in the future.
The findings are published in the journal Molecular Ecology.