Featured Research

from universities, journals, and other organizations

Satellite tagging maps the secret migration of white sharks

Date:
April 4, 2013
Source:
BioMed Central
Summary:
Long-life batteries and satellite tagging have been used to fill in the blanks of female white sharks' (Carcharodon carcharias) lifestyles. New research defines a two year migratory pattern in the Pacific Ocean. Pregnant females travel between the mating area at Guadalupe Island and nursery in Baja California, putting them and their young at risk from commercial fishing.

White shark.
Credit: Michael L. Domeier

Long-life batteries and satellite tagging have been used to fill in the blanks of female white sharks' (Carcharodon carcharias) lifestyles. Research published in the launch edition of BioMed Central's open access journal Animal Biotelemetry defines a two year migratory pattern in the Pacific Ocean. Pregnant females travel between the mating area at Guadalupe Island and nursery in Baja California, putting them and their young at risk from commercial fishing.

White sharks are pelagic much of their time, living in the open ocean. However they are also philopatric, in that they return to the same place to find a mate. This commute can be far-ranging, including the Hawaiian Islands, California, and Mexico but while males have been reported returning yearly to mating sites, the behavior of females has before now been more secretive.

Dr Michael Domeier and Nicole Nasby-Lucas from the California based Marine Conservation Science Institute mapped the migration patterns of female white sharks using satellite-linked radio-telemetry tags.

Female white sharks were found to follow a two-year migration pattern with four distinct phases. Firstly the pregnant females left Guadalupe Island, Mexico and remained offshore for most of their 18 month gestation (on average 465 days). This pelagic area was much larger than the foraging area used by males and in fact the females tended to avoid the male's foraging area while the males were present.

The second phase was a two month sojourn in the coastal waters of Baja California where the sharks gave birth. After leaving the nurseries the female sharks began a migratory path back to Guadalupe Island in such a way as to avoid males until ready to reproduce. Finally the mating n phase at Guadalupe Island lasted up to four and a half months before the two year cycle began again.

Females that skipped a year of reproduction returned to the breeding site after only a single year migration.

Dr Domeier commented, "During the mating phase both males and female sharks are seen with injuries. It's unclear whether males are fighting over food or females or both, but this aggression may be why the females avoid males at other times. Our tracking has also highlighted a previously unknown period of vulnerability when the females are exposed to commercial fishing off the coast of North America."

Open access publisher BioMed Central is proud to announce the launch of Animal Biotelemetry. This journal joins our growing portfolio in ecology and conservation and marks a significant development in the area of Animal Biotelemetry research.


Story Source:

The above story is based on materials provided by BioMed Central. Note: Materials may be edited for content and length.


Journal Reference:

  1. Michael L Domeier and Nicole Nasby-Lucas. Two-year migration of adult female white sharks (Carcharodon carcharias) reveals widely separated nursery areas and conservation concerns. Animal Biotelemetry, 2013; 1: 2 [link]

Cite This Page:

BioMed Central. "Satellite tagging maps the secret migration of white sharks." ScienceDaily. ScienceDaily, 4 April 2013. <www.sciencedaily.com/releases/2013/04/130403200154.htm>.
BioMed Central. (2013, April 4). Satellite tagging maps the secret migration of white sharks. ScienceDaily. Retrieved August 31, 2014 from www.sciencedaily.com/releases/2013/04/130403200154.htm
BioMed Central. "Satellite tagging maps the secret migration of white sharks." ScienceDaily. www.sciencedaily.com/releases/2013/04/130403200154.htm (accessed August 31, 2014).

Share This




More Plants & Animals News

Sunday, August 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Washington Wildlife Center Goes Nuts Over Baby Squirrels

Washington Wildlife Center Goes Nuts Over Baby Squirrels

Reuters - US Online Video (Aug. 30, 2014) An animal rescue in Washington state receives an influx of orphaned squirrels, keeping workers busy as they nurse them back to health. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Newsy (Aug. 29, 2014) In a new study, a promising experimental treatment for Ebola managed to cure a group of infected macaque monkeys. Video provided by Newsy
Powered by NewsLook.com
Killer Amoeba Found in Louisiana Water System

Killer Amoeba Found in Louisiana Water System

AP (Aug. 28, 2014) State health officials say testing has confirmed the presence of a killer amoeba in a water system serving three St. John the Baptist Parish towns. (Aug. 28) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins