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 March 2015 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

People & Company News

Carnival Sails to Profit

The world's largest cruise company Miami-based Carnival Corp reported a net profit of $49 million, or 6 cents per share in the first quarter ended Feb. 28.   That

Ukraine Arrests Turkish Ship for Visiting Crimean Port

Turkey owned merchant ship flying the flag of Tuvalu was arrested by Ukrainian authorities over a visit it made to a port in Crimea, reports Reuters. The ship's captain detained.

USCG Flush Ice down River Systems to Facilitate Shipping

The Coast Guard cutter fleet is flushing ice through the Great Lakes river systems to prevent ice jams and facilitate commercial shipping as the shipping season

Environmental

USCG Flush Ice down River Systems to Facilitate Shipping

The Coast Guard cutter fleet is flushing ice through the Great Lakes river systems to prevent ice jams and facilitate commercial shipping as the shipping season

Chile Desert Rains Sign of Climate Change

The heavy rainfall that battered Chile's usually arid north this week happened because of climate change, a senior meteorologist said, as the region gradually

Mexico Unveils National Strategy ahead of Paris Climate Talks

Mexico on Friday said it will cap its greenhouse gas emissions by 2026, becoming one of the first countries to formally submit its national climate plan the

Marine Science

Changes in Aker Solutions' Top Deck

Tore Sjursen will assume the position as executive vice president for operational improvement and risk management at Aker Solutions on April 1. Knut Sandvik

Salvage, Wreck Removal Beset with Chronic Problems

The basic nature of maritime casualties, salvage and wreck removal has evolved rapidly over the last few years. Ships and offshore constructions have become more technologically elaborate,

Moskito to Recover Oil from Sunken Wrecks

A tool for removing oil in submerged vessels was developed in Norway by Miko Marine. Moskito is designed to address the pollution threat that exists with the

Ocean Observation

Is China Building a Naval Base in Africa?

Recently, The Namibian reported the existence of a "confidential letter from Namibia's ambassador to China, Ringo Abed, to Namibia's foreign minister stating that

Indonesia Partners with China on Maritime

Indonesian President Joko “Jokowi” Widodo and Chinese President Xi Jinping pledged increased maritime cooperation during the formers visit to China.   The joint

Damen joins World Ocean Council

Dutch-based Damen Shipyards Group has become the latest member of the World Ocean Council (WOC).    The global shipbuilder headquartered in the Netherlands is

 
 
Maritime Security Maritime Standards Naval Architecture Navigation Pipelines Port Authority Ship Simulators Shipbuilding / Vessel Construction Sonar Winch
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: 0.2156 sec (5 req/sec)