PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

New study finds extreme longevity in white sharks

2014-01-09
(Press-News.org) Contact information: Media Relations Office
media@whoi.edu
508-289-3340
Woods Hole Oceanographic Institution
New study finds extreme longevity in white sharks Great white sharks—top predators throughout the world's ocean—grow much slower and live significantly longer than previously thought, according to a new study led by the Woods Hole Oceanographic Institution (WHOI).

In the first successful radiocarbon age validation study for adult white sharks, researchers analyzed vertebrae from four females and four males from the northwestern Atlantic Ocean. Age estimates were up to 73 years old for the largest male and 40 years old for the largest female.

"Our results dramatically extend the maximum age and longevity of white sharks compared to earlier studies," said Li Ling Hamady, MIT/WHOI Joint Program student and lead author of the study published in PLOS ONE. "Understanding longevity of the species, growth rate, age at sexual maturity, and differences in growth between males and females are especially important for sustainable management and conservation efforts."

Age determination in fish relies primarily on analyzing growth increments in mineralized tissue, such as otoliths (ear bones), vertebrae, and fin rays. These grow throughout a fish's life, adding annual rings, similar to growth rings in trees.

Estimating age in white sharks can be challenging. While vertebrae are constructed of layers of tissue, laid down sequentially over an individual's lifetime, the alternating light/dark banding patterns can be narrow and less distinct than in other species, and the bands don't necessarily signify annual growth.

"Traditionally, ageing sharks has relied on the assumption that band pairs are annual. In many cases this has been proven correct for part or all of a species life, however in more and more cases this is being disproven," said coauthor Lisa Natanson, a fisheries biologist at NOAA's Northeast Fisheries Science Center (NEFSC) lab in Narragansett, R.I.

In previous studies, which assumed annual deposition of growth bands, the oldest white shark individuals identified were from the southwestern Pacific Ocean at 22 years old and the western Indian Ocean at 23 years old.

For this study, researchers took advantage of radiocarbon produced by thermonuclear device testing done during the 1950s and 1960s. Radiocarbon mixed from the atmosphere into the ocean, and was incorporated into the tissues of marine organisms living during that time period. The rise in radiocarbon—measured as ∆14C—gave researchers a specific spot in time pinpointed in the vertebra layers, which can be used as a "time stamp" to help determine the age of an animal.

The National Ocean Sciences Accelerator Mass Spectrometry Facility at WHOI conducted radiocarbon analysis on collagen in the white shark vertebrae. All of the vertebrae samples came from white sharks caught in the northwestern Atlantic Ocean from 1967 to 2010 that were archived at the NEFSC lab in Narragansett, which has the largest collection of this kind. The samples were also digitally photographed with a camera attached to a stereomicroscope using reflected light for counting growth bands.

"This research demonstrates the power of applying cutting-edge techniques in isotope geochemistry to answer fundamental questions in ocean ecology," said co-author Simon Thorrold, a biologist at WHOI and Hamady's Ph.D. advisor. "The radiocarbon time stamp in white shark vertebrae provides irrefutable evidence of white shark longevity that had proved to be impossible to verify using traditional age estimation methods."

Researchers found that band pairs are laid down on an annual basis in small to medium-large sized white sharks in the northwestern Atlantic. However, the largest individuals may experience a change in the rate of vertebral material deposition at some point after maturity, or the bands may become so thin that they are unreadable.

Assuming a lifespan estimate of 70 years or more, white sharks may be among the longest-lived cartilaginous fishes. While they are predominantly found in temperate and subtropical waters, white sharks migrate long distances and can be found throughout the global ocean.

White sharks are considered "vulnerable" worldwide. Since individuals are slow growing, and mature late, white shark populations could be even more sensitive to fishing, environmental and other pressures.

"These findings change the way we model white shark populations and must be taken into consideration when formulating future conservation strategies," said co-author Greg Skomal, a WHOI adjunct scientist and MA Marine Fisheries biologist.

INFORMATION:

This research was funded by a grant from the National Science Foundation, Division of Ocean Sciences.

The Woods Hole Oceanographic Institution is a private, non-profit organization on Cape Cod, Mass., dedicated to marine research, engineering, and higher education. Established in 1930 on a recommendation from the National Academy of Sciences, its primary mission is to understand the ocean and its interaction with the Earth as a whole, and to communicate a basic understanding of the ocean's role in the changing global environment.

END



ELSE PRESS RELEASES FROM THIS DATE:

Study: Seashell loss due to tourism increase may have global impact

2014-01-09
Study: Seashell loss due to tourism increase may have global impact GAINESVILLE, Fla. --- Global tourism has increased fourfold over the last 30 years, resulting in human-induced seashell loss that may harm natural habitats worldwide, according to a University ...

Penn researchers develop 'personalized advantage index,' a new decision-making tool

2014-01-09
Penn researchers develop 'personalized advantage index,' a new decision-making tool One of the primary social motivations for scientific research is the ability to make better decisions based on the results. But whether it is deciding what material to use in making ...

Slow-evolving elephant shark genome is first to be sequenced from cartilaginous fish

2014-01-09
Slow-evolving elephant shark genome is first to be sequenced from cartilaginous fish SF State biology professor publishes findings in the journal Nature SAN FRANCISCO -- A team of researchers including SF State Assistant Professor of Biology Scott Roy has sequenced ...

Higher risk of birth problems after assisted conception

2014-01-09
Higher risk of birth problems after assisted conception A University of Adelaide study has shown that the risk of serious complications such as stillbirth, preterm birth, low birth weight and neonatal death is around twice as high for babies conceived ...

Blood pressure study points to more equitable care in England than America

2014-01-09
Blood pressure study points to more equitable care in England than America In the US but not in England, patients on low incomes with high blood pressure have their condition managed poorly compared with those who earn more. A new study comparing blood pressure ...

Penn Medicine epidemiologists find bed bug hotspots in Philadelphia, identify seasonal trends

2014-01-09
Penn Medicine epidemiologists find bed bug hotspots in Philadelphia, identify seasonal trends Philadelphia infestations are increasing, with many reports in South Philadelphia PHILADELPHIA—A new study from Penn Medicine epidemiologists ...

Literary mood reflects the economic mood of past 10 years, study finds

2014-01-09
Literary mood reflects the economic mood of past 10 years, study finds The frequency of words expressing misery and unhappiness in books reflects the economic conditions in the 10 years prior to the work's composition, according to researchers in Bristol ...

Scientists unlock evolution of cholera, identify strain responsible for early pandemics

2014-01-09
Scientists unlock evolution of cholera, identify strain responsible for early pandemics Working with a nearly 200-year-old sample of preserved intestine, researchers at McMaster University and the University of Sydney have traced the bacterium behind a global ...

Organic mega flow battery promises breakthrough for renewable energy

2014-01-09
Organic mega flow battery promises breakthrough for renewable energy Harvard technology could economically store energy for use when the wind doesn't blow and the sun doesn't shine Cambridge, Mass. – January 8, 2014 – A team of Harvard scientists and engineers has demonstrated ...

Researchers unveil rich world of fish biofluorescence

2014-01-09
Researchers unveil rich world of fish biofluorescence Technology-driven study finds about 180 glowing species, highlights new potential source for biomedical fluorescent proteins A team of researchers led by scientists from the American Museum of Natural ...

LAST 30 PRESS RELEASES:

Thirty-year mystery of dissonance in the “ringing” of black holes explained

Less intensive works best for agricultural soil

Arctic rivers project receives “national champion” designation from frontiers foundation

Computational biology paves the way for new ALS tests

Study offers new hope for babies born with opioid withdrawal syndrome

UT, Volkswagen Group of America celebrate research partnership

New Medicare program could dramatically improve affordability for cancer drugs – if patients enroll

Are ‘zombie’ skin cells harmful or helpful? The answer may be in their shapes

University of Cincinnati Cancer Center presents research at AACR 2025

Head and neck, breast, lung and survivorship studies headline Dana-Farber research at AACR Annual Meeting 2025

AACR: Researchers share promising results from MD Anderson clinical trials

New research explains why our waistlines expand in middle age

Advancements in muon detection: Taishan Antineutrino Observatory's innovative top veto tracker

Chips off the old block

Microvascular decompression combined with nerve combing for atypical trigeminal neuralgia

Cutting the complexity from digital carpentry

Lung immune cell type “quietly” controls inflammation in COVID-19

Fiscal impact of expanded Medicare coverage for GLP-1 receptor agonists to treat obesity

State and sociodemographic trends in US cigarette smoking with future projections

Young adults drive historic decline in smoking

NFCR congratulates Dr. Robert C. Bast, Jr. on receiving the AACR-Daniel D. Von Hoff Award for Outstanding Contributions to Education and Training in Cancer Research

Chimpanzee stem cells offer new insights into early embryonic development

This injected protein-like polymer helps tissues heal after a heart attack

FlexTech inaugural issue launches, pioneering interdisciplinary innovation in flexible technology

In Down syndrome mice, 40Hz light and sound improve cognition, neurogenesis, connectivity

Methyl eugenol: potential to inhibit oxidative stress, address related diseases, and its toxicological effects

A vascularized multilayer chip reveals shear stress-induced angiogenesis in diverse fluid conditions

AI helps unravel a cause of Alzheimer's disease and identify a therapeutic candidate

Coalition of Autism Scientists critiques US Department of Health and Human Services Autism Research Initiative

Structure dictates effectiveness, safety in nanomedicine

[Press-News.org] New study finds extreme longevity in white sharks