Nature & Environment
White Sharks Live Longer Than 70 Years and Mature More Slowly Than Previously Thought
Catherine Griffin
First Posted: Feb 19, 2015 09:34 AM EST
Scientists have taken a closer look at some of the most effective predators in the ocean: white sharks. Now, they've found that these animals grow far more slowly and mature much later than previously thought, which could have implications for conservation efforts.
The researchers examined the banding patterns on vertebrae from white sharks collected between 1963 and 2010 by the NOAA Fisheries Apex Predators Program. The samples came from white sharks caught on research cruises, taken by commercial and recreational fishing vessels, or landed at recreational fishing tournaments.
The distribution of white sharks is actually well documented, though the species itself is considered rare. Much of what we know today about the species comes from distribution records and just a handful of observations and dead specimens.
"Using the longevity data obtained from our first study, we are now able to describe not just how long white sharks live, but also the growth rate for this species, which is remarkably slower than anybody thought," said Lisa Natanson, lead author of the new study, in a news release.
In order to construct the growth curve, the researchers looked at band pair counting from 77 white sharks. This revealed that these sharks could live longer than 73 years. Not only that, but males sexually matured around the age of 26 and females around the age of 33. That's far later than currently accepted estimates of 4 to 10 years for males and 7 to 13 years for females.
Because these animals are slow-growing and long-lived with low reproduction rates, they're especially vulnerable to fishing. If fishing isn't managed properly, these sharks may be in danger. In addition, with lifespan estimates of 70 years or more, these sharks may be among the longest-lived fishes.
The findings are published in the journal Marine and Freshwater Research.
For more great science stories and general news, please visit our sister site, Headlines and Global News (HNGN).
See Now:
NASA's Juno Spacecraft's Rendezvous With Jupiter's Mammoth Cyclone
TagsShark ©2024 ScienceWorldReport.com All rights reserved. Do not reproduce without permission. The window to the world of science news.
More on SCIENCEwr
First Posted: Feb 19, 2015 09:34 AM EST
Scientists have taken a closer look at some of the most effective predators in the ocean: white sharks. Now, they've found that these animals grow far more slowly and mature much later than previously thought, which could have implications for conservation efforts.
The researchers examined the banding patterns on vertebrae from white sharks collected between 1963 and 2010 by the NOAA Fisheries Apex Predators Program. The samples came from white sharks caught on research cruises, taken by commercial and recreational fishing vessels, or landed at recreational fishing tournaments.
The distribution of white sharks is actually well documented, though the species itself is considered rare. Much of what we know today about the species comes from distribution records and just a handful of observations and dead specimens.
"Using the longevity data obtained from our first study, we are now able to describe not just how long white sharks live, but also the growth rate for this species, which is remarkably slower than anybody thought," said Lisa Natanson, lead author of the new study, in a news release.
In order to construct the growth curve, the researchers looked at band pair counting from 77 white sharks. This revealed that these sharks could live longer than 73 years. Not only that, but males sexually matured around the age of 26 and females around the age of 33. That's far later than currently accepted estimates of 4 to 10 years for males and 7 to 13 years for females.
Because these animals are slow-growing and long-lived with low reproduction rates, they're especially vulnerable to fishing. If fishing isn't managed properly, these sharks may be in danger. In addition, with lifespan estimates of 70 years or more, these sharks may be among the longest-lived fishes.
The findings are published in the journal Marine and Freshwater Research.
For more great science stories and general news, please visit our sister site, Headlines and Global News (HNGN).
See Now: NASA's Juno Spacecraft's Rendezvous With Jupiter's Mammoth Cyclone