Lemon Sharks Go Back Home to Give Birth, Find Researchers

SeaDiscovery.com
Monday, December 09, 2013
Lemon Shark: Photo Wiki CCL

In the marine world, natal philopatry (animals returning to their own birthplace to give birth to their young) has been documented in salmon, seals, and some sea turtles; but for the first time, the phenomenon has been recognized in lemon sharks, researchers at the Field Museum in Chicago discover.

What is a lemon shark?
“A lemon shark is a large coastal shark, mainly found in the western Atlantic,” says Kevin Feldheim, A. Watson Armour III Manager of the Pritzker Laboratory for Molecular Systematics and Evolution at The Field Museum, who did his dissertation on these sharks.  “They are about as sharkey-looking as they come, and are called lemon sharks because their bellies are light, almost yellow, like a lemon.”

For the past 20 years, Field Museum scientists and collaborators in the Bahamas have been tracking female lemon sharks from birth through sexual maturity, and have found that some females do return to their birthplace to give birth to their pups.

Research
Each year, young sharks 0-2 years old, are collected and tagged using the same microchips that pet owners can place in their dogs.  The microchip acts as a collar of sorts, and can provide information about the identity and age of the animal.  In addition, a piece of the shark’s fin is taken for genetic analysis at the Pritzker Laboratory, right here at The Field Museum.

Using DNA from the fin, Field Museum scientists were able to create a database and determine family relationships, based on the similarity of the DNA sequences.

“We use a program that will create a parental pedigree for us, using the DNA of the newborn sharks,” said Feldheim.  “We can tell if a baby shark belongs to a female whose DNA is already in our database, and these relationships are confirmed by catching the animals.  For example, in 2008, we caught and tagged a pregnant female, and four years later, we caught several of her babies.”

“What is novel about our findings is that [lemon shark] nursery areas play a much stronger role in supporting local populations.  So, conservation of local populations needs to occur at a much finer scale (in addition to the needed larger regional scale)," concludes Feldheim.

Source: The Field Museum
 

Maritime Reporter November 2014 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

People & Company News

Port of Houston Expecting Record Year

The Port of Houston Authority is expecting 2014 to close as a banner year for the port, with 34 million tons of cargo handled through November, Executive Director

Hapag-Lloyd Completes CSAV Merger Capital Increase

Hapag-Lloyd completed the planned capital increase of EUR 370 million (approximately $452.5 million) as part of the business combination with the Chilean shipping

San Jacinto College Breaks Ground on New Training Center

San Jacinto College has broken ground along the Port of Houston for its new 45,000-square-foot Maritime Training Center.   At the site of 3700 Old Highway 146 in La Porte,

Environmental

NZ Report: Human Error to Blame for Rena Grounding

New Zealand's Transport Accident Investigation Commission (TAIC) published its final report into the grounding of containership Rena in October 2011. The TAIC’s

Costa Rica Approves APM Terminals Project

Port operator APM Terminals, a unit of Denmark's A.P. Moller-Maersk, said on Friday Costa Rica's environment agency had approved the construction of its Moin Container Terminal project.

NOAA: US to See More Floods from Sea Level Rise

Most of U.S. coast may see 30 or more days a year of floods up to 2 feet above high tides. By 2050, a majority of U.S. coastal areas are likely to be threatened

Marine Science

NOAA: US to See More Floods from Sea Level Rise

Most of U.S. coast may see 30 or more days a year of floods up to 2 feet above high tides. By 2050, a majority of U.S. coastal areas are likely to be threatened

Damen Shipyards Galati wins Dutch Romanian Award

Damen Shipyards Galati has been presented with the Dutch Romanian Business Award for its Corporate Social Responsibility plan, particularly the Group’s community investment initiatives.

Lowrance Renews Insight Genesis College Cup

Lowrance®, a world-leading brand in fishing electronics since 1957— announced today the renewal of its Insight Genesis™ College Cup. In its second year, the

Ocean Observation

NOAA: US to See More Floods from Sea Level Rise

Most of U.S. coast may see 30 or more days a year of floods up to 2 feet above high tides. By 2050, a majority of U.S. coastal areas are likely to be threatened

DYT Yacht Transport Carries M/V OCEARCH

The 126-foot research vessel M/V OCEARCH is currently making its way from Port Everglades, Florida to Brisbane, Australia on board DYT Yacht Transport’s semisubmersible

Talisman Sinopec Closes North Sea Platform Ahead of Storm

Talisman Sinopec Energy UK has closed its Buchan Alpha platform in the North Sea, the company said on Wednesday, ahead of an expected severe winter storm. The

 
 
Maritime Security Maritime Standards Naval Architecture Navigation Offshore Oil Pipelines Pod Propulsion Salvage Ship Electronics Shipbuilding / Vessel Construction
rss | archive | history | articles | privacy | terms and conditions | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.4937 sec (2 req/sec)