Reproduction Related Content

Apr 9 2013 - 9:46am
Instead of females, male seahorses carry the developing seahorse embryos in a kangaroo-like pouch. During mating season, the female deposits her eggs into the pouch, and the male fertilizes them. After about two weeks of development, out pop the seahorse fry, ready to swim off and explore the ocean...
Oct 8 2012 - 12:58pm
A coral (Montastraea faveolata) has just spawned. Each of the hundreds of polyps living in the colony releases a small pink bundle of sperm and eggs. Read more about coral spawing and watch a spawning event. 
Jan 26 2010 - 11:46am
A male mudflat fiddler crab (Uca rapax) waves its huge claw to impress females and threaten male competitors. More about mangrove swamps and forests can be found in our Mangroves featured story.
Jan 26 2010 - 11:46am
What are corals? Corals themselves are animals. But tropical reef-building corals have tiny plant-like organisms living in their tissue. The corals couldn’t survive without these microscopic algae–called zooxanthellae (zo-zan-THELL-ee). This cutaway diagram of a coral polyp shows where the...
Sep 11 2012 - 4:13pm
Over the last few days, a video of hermit crabs stampeding across the rocky shores of St. John in the U.S. Virgin Islands has taken the internet by storm. Where are the hermit crabs going, and why?
May 16 2012 - 12:20pm
Male northern elephant seals face off on the beach by vocalizing through their extended noses, called proboscises. Every winter, when the seals return to the beach where they were born to breed, males arrive first to tussle for territory. The winners of these fights are the "alpha" males, and they...
Dec 4 2012 - 3:02pm
Most wild seahorses (here the thorny seahorse Hippocampus histrix) are monogamous and some species mate for life. Searching for mates can be difficult and risky since seahorses are poor swimmers, found in low densities and rely on camouflage to hide from predators. By remaining faithful to one...
Jul 24 2012 - 9:47pm
A gentoo penguin (Pygoscelis papua) mother stands with her chick in Antarctica. When walking on land, gentoo penguins waddle with their long tails dragging behind them; but in the water, they are the fastest penguins of them all, reaching swimming speeds of 36 kilometers per hour (around 22 miles...
Jul 23 2012 - 9:30am
Two California market squids, Loligo opalescens, mate in the waters off of California's Channel Islands. While spawning, the males' arms blush red as he embraces the female; a warning to other competing males to back-off.
Jun 21 2011 - 1:58pm
“Every four years, sockeyes come inland from the Pacific to spawn. The year 2010 was the largest run in 100 years, reaching more than 30 million fish. On this day, I waited for the right sunlight, then quietly slipped into the river. Fighting the rush of the current, I positioned myself in front of...
Jan 10 2013 - 10:47am
Sharks have young in three different ways. After internal fertilization, some species lay a thick egg case that encloses the shark embryo (seen in the photo here). Most species are ovoviviparous, which means that the shark hatches and develops within the female shark and is born live. A third way (...
Jul 30 2012 - 10:31am
Male fiddler crabs, like this one collected on Moorea, wave their enlarged claw as way of signaling to other crabs, especially during mating season. Learn more about the Island of Moorea in the Pacific Ocean, including its biodiversity and the scientific effort to catalog all the life found on its...
Sep 7 2012 - 3:38pm
This close-up view of salps, which have aggregated together into a long chain, have brilliant red guts from eating red plankton. They were observed by researchers with the Census of Marine Zooplankton in the Sargasso Sea.
May 11 2012 - 3:17pm
Cardinalfish (Cheilodipterus sp.) dads do their part to protect their eggs by gingerly carrying them in their mouths. However, the dads could easily swallow the whole bunch in one gulp! To keep her eggs alive, the cardinalfish mom will often lay a number of yolkless dummy eggs along with the real...
May 10 2013 - 9:27am
The Laysan albatross (Phoebastria immutabilis) breeds mainly in Hawaii and other Pacific islands where male and female pairs will incubate their egg for nine weeks. The pair participates in an elaborate courtship dance where movements and noises bond them together for the rest of their lives. After...
Jun 14 2011 - 2:43pm
If youngsters get cared for at all, the mother is usually involved. But in fish and a few other groups where eggs are not abandoned, fathers are the primary care providers. Males are sometimes such devoted dads that it takes longer for them to care for the young than it does for the females to...
Oct 20 2010 - 7:59am
Welcome to Citizens of the Sea, a new blog series where ocean life comes to life. Our book by the same name came out in September, but no sooner had it gone off to the printer than new ocean stories started streaming in. So every other week, we’ll use this series to explore some interesting aspect...
Jan 26 2010 - 11:45am
Phoenix swimming with her calf in February 2007 in the Southeast calving grounds off the coasts of Georgia and Florida. Researchers track these highly endangered whales (there are only about 450 of them left) very closely and use their skin markings to confirm sightings. The New England Aquarium...
Jan 26 2010 - 11:45am
A male mudflat fiddler crab (Uca rapax) waves its huge claw to impress females and threaten male competitors. More about the animals and plants living in mangrove ecosystems can be found in the Mangroves section.
Ten Things You Never Knew About Seahorses
Jan 2 2013 - 1:01pm
  By Lindsay Aylesworth, Project Seahorse
Jan 26 2010 - 11:45am
These newly hatched squid larvae (Doryteuthis plei) are tinier than the head of a dissecting pin, which is even smaller than a common sewing pin. More about the giant squid can be found in our Giant Squid featured story.
May 11 2012 - 2:12pm
This Mother's Day we honor moms everywhere. Whether with gills, fins, flippers, claws, tentacles or arms, we appreciate all you do for us. Here is a Happy Mother's Day salute to devoted moms above the waves and below. To learn more about ocean moms check out our blog post on marine menopausal...
Jan 26 2010 - 11:45am
Smaller than the head of a pin, this squid embryo looks almost like a miniature adult. It is from a medium-sized squid - the arrow squid (Doryteuthis plei). Explore more cephalopds and the largest known squid, the Giant Squid, on the Ocean Portal.
May 6 2011 - 3:07pm
In honor of Mother's Day, the Citizens of the Sea blog salutes ocean-going mothers everywhere. Especially a 60 year-old albatross named Wisdom. She holds the seabird records for both oldest bird and oldest new mother. No stranger to motherhood, it is estimated that she has already birthed 30-35...