Tuesday, May 24, 2011

Eggs of the Intertidal

Eggs found in the intertidal are often the most difficult items to indentify.  Seattle Aquarium Beach Naturalists have been equipped with ID sheets to make the life easier but for others perhaps this group of images will be of some use.  New image:  illustration added at bottom of Pile Worm eggs...these egg masses are often found floating in the drift in summer and have been a mystery for some time.  This ends up as a clump of dirty tan eggs about the size of a jumbo chicken eggs....individual eggs are not visible without a microscope.  Will try to add image of actual egg mass next time I see one.
Things to Remember:
Arthropod females hold eggs and release hatched larvae (crabs, barnacles, shrimp).
Echinoderms broadcast spawn and do not attach eggs (a few Sea Stars retain eggs till they hatch)
Most worms broadcast spawn some lay attached eggs.
Some Mollusks broadcast spawn....(chitons, limpets, some snails).
Fish often attach eggs (Scuplins, Herring, Lingcod, Smelt) others broadcast spawn (Cod, Flounder) or have live births (Dogfish Sharks, Perch, Rockfish)
Cnidarians mostly broadcast spawn or divide asexually or retain eggs and release tiny adults                    

Frilled Whelks laying eggs

Dungeness Crab with eggs

Gravid Tidepool Sculpin

Unidentified Polychete worm eating Bubble Shell Eggs

Gravid Tidepool Sculpin

Northern Kelp Crab with eggs


Spinyhead Sculpin male with eggs
Sea Lemon laying eggs

Barnacle Eating Nudibranch with eggs

Big Skate eggs in egg case

Black-clawed Crab with eggs

Bubble Snail with eggs

Bubble Snail with eggs

Burrowing Sea Cucumber with eggs

Gumboot Chiton laying eggs

N. Clingfish with eggs

Crescent Gunnel with eggs


Ghost Shrimp with eggs

Green Annelid worm eggs
Green Annelid worm that laid eggs above

Graceful Cancer Crab with eggs

Lacuna snail eggs on eelgrass

Plainfin Midshipman eggs
Plainfin Shipman male with eggs

Moon Snail with egg case (sand collar)

Hairy Triton with eggs

Red Octopus with eggs
Giant Pacific Octopus with eggs

Sculpin eggs

Shaggy Mouse sea slug with eggs

Sea Star female spawning

Sitka Shrimp with eggs

Taylor's Sea Hare eggs

Frilled Dogwinkle with eggs

Sea Lemon sea slug eggs

Opalescent Sea Slug with eggs

Opalescent Sea Slug eggs on Moon Snail sand collar
Frilled Whelk egg capsules

Frilled Whelks mating

Rockweed Isopods mating

Aggregate Anemone dividing

Emarginated Whelk egg capsules

Flatworm and egg masses

Rockweed Isopod with young at pouch

Rockweed Isopod with young at pouch

Plainfin Midshipman eggs

Porcelain Crab with eggs

Lacuna Snail with eggs

Hairy Shore Crab with eggs
Noble Sea Lemon eggs

Lacuna Snail eggs

Lacuna snail with egg mass on shell
Pile Worm eggs


  1. Hello
    I really want to tell you that it's just amazing and unique blog.i never seen such beautiful blog before.actually identification of different eggs
    are really very difficult.good job.
    Sea animals

  2. I just found this, and it has the eggs I had despaired of finding. (The green annelid eggs.)

    Thank you, thank you, thank you!

    Bookmarked. I'll be back, often.

  3. Just found your marvelous blog and am having a wonderful time looking at many of your posts. Wish I had found this particular post regarding eggs a couple of years ago when I began to learn about intertidal zone creatures... the folks at the dive shop (!) told me that the barnacle-eating nudibranch eggs were sponges...
    Looking forward to seeing more and more of your fabulous blog!

  4. Buzz,
    I couldn't agree more with the comments above. All of your blog info is phenomenal. If only I had the brain to retain it all! Oh well, I guess that means I will return often!!

    1. Thank's much Leslie for the nice comment......makes doing this all the more fun.

  5. Thank you! I volunteer with 1st, 2nd, and 3rd graders and help them understand beach finds and ecology. Sculpin eggs. That's what they are! Your photo of Moonsnail and egg band is super too.

  6. Wow! Thank you! I'm inspired to go out and try to find these guys.

    1. Thanks much for the comment.....lots of people hunting eggs today :)

  7. Buzz this is such a GREAT blog! Please keep them coming! Lisa