Channel: Deep Look

Category: Science & Technology

Tags: pbseducationclaspereggarthropodslarvaecrabsseamicroscopematingmarine biologylimulus polyphemuslarvadocumentarywildlifeintertidalmacroeggsatlantic horseshoe crabtelsonhow do horseshoe crabs lay eggsnaturehatchdeep lookhorseshoe crab matingevolutionhatchingtideshorseshoemoonspawnoceanhow do horseshoe crabs matearachnidbeachscience4kmigrationhorseshoe crabembyrospawning horseshoe crabswildinvertebratescrabhorseshoe crabsreproduction

Description: Horseshoe crabs may look scary, but when it's springtime in Delaware Bay, millions of these arthropods show they're lovers, not fighters. They lay masses of blue-green eggs up on the shore. At just the right time, they pop and release the larvae within the sea. WATCH our crab collab episode with OVERVIEW on@PBS Terra! youtu.be/PSX4NvvgmJM DEEP LOOK is an ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Explore big scientific mysteries by going incredibly small. --- Each spring during May and June, Atlantic horseshoe crabs gather by the millions along the East Coast of North America with only one thing on their mind — a springtime spawning spree! From Maine to the Gulf of Mexico they seek out calm bays and estuaries, waiting for the highest tides to emerge from the waves. They dig down into the wet sand and deposit huge numbers of pea-sized eggs. David R. Smith, a biological statistician who studies horseshoe crabs for the U.S.Geological Survey, has come to Slaughter Beach, Delaware, to witness the spectacle under the glow of a full moon. “It's sort of like looking back in time,” says Smith, “That same scene of these marine creatures coming to the water's edge on a quiet sandy beach to spawn has been repeated for millions and millions of years without much variation.” --- What do horseshoe crabs eat? Horseshoe crabs mostly eat worms and mollusks from the seafloor. But they aren’t picky, they’ll eat other things like small fish and different crustaceans. --- Why do horseshoe crabs lay their eggs on land? By laying their eggs in the damp sand, they protect their eggs from the many predators that live in the sea. It allows their offspring a chance to develop before another high tide carries them into the sea. --- Why do horseshoe crabs have blue blood? Like other mollusks, horseshoe crabs have blood that carries oxygen using a copper-containing protein called hemocyanin. The hemocyanin turns blue when exposed to oxygen. Vertebrates like humans have iron-containing hemoglobin in their blood, causing it to turn red when exposed to oxygen. ---+ Find additional resources and a transcript on KQED Science: kqed.org/science/1976488/once-a-spawn-a-time-horseshoe-crabs-mob-the-beach ---+ More great Deep Look episodes: These Fish Are All About Sex on the Beach | Deep Look youtu.be/j5F3z1iP0Ic For Pacific Mole Crabs It's Dig or Die | Deep Look youtu.be/tfoYD8pAsMw Decorator Crabs Make High Fashion at Low Tide | Deep Look youtu.be/OwQcv7TyX04 ---+ Shoutout! 🏆Congratulations🏆 to the following 5 fans on our Deep Look Community Tab for correctly answering that the body part a male horseshoe crabs use to grab onto their mates is a clasper, a modified pedipalp! Sinister Omen SARA FATIMA Anirudh Anilkumar Uwis Qurni Abdullah hudson urruttia ---+ Thank you to our Top Patreon Supporters ($10+ per month)! Chris B Emrick Burt Humburg David Deshpande Karen Reynolds Daisuke Goto Adam Kurtz Allison & Maka Masuda dane rosseter Wild Turkey Berian James Nathan Jewsbury Companion Cube Tianxing Wang Josh Kuroda Mark Jobes Cindy McGill Blanca Vides Kevin Judge Jana Brenning Supernovabetty Titania Juang Aurora Anastasia Grinkevic monoirre Roberta K Wright Leonhardt Wille Syniurge Rick Wong KW Carrie Mukaida El Samuels Mehdi Kristy Freeman Gerardo Alfaro Nicky O. Mary Truland Cristen Rasmussen Scott Faunce Ed Gandia SueEllen McCann Jeremiah Sullivan Noreen Herrington Kelly Hong Misia Clive Shelley Pearson Cranshaw Sonia Tanlimco Kallie Moore Teresa Lavell Nicolette Ray Laurel Przybylski Louis O'Neill Carlos Carrasco Caitlin McDonough Delphine Tseng Elizabeth Ann Ditz Joshua Murallon Robertson Levi Cai TierZoo Silvan chckncurry ---+ Follow KQED Science and Deep Look: Instagram: instagram.com/kqedscience Twitter: twitter.com/kqedscience ---+ About KQED KQED, an NPR and PBS affiliate in San Francisco, California, serves Northern California and beyond with a public-supported alternative to commercial TV, radio and web media. Funding for Deep Look is provided in part by PBS Digital Studios. Deep Look is a project of KQED Science, the largest science and environment reporting unit in California. KQED Science is supported by The National Science Foundation, the Dirk and Charlene Kabcenell Foundation, the Vadasz Family Foundation, the Gordon and Betty Moore Foundation, Campaign 21 and the members of KQED.