Soft Wrackline Objects

Skate Eggcase Lion's Mane Buoy Barnacle

What are they?

The wrackline or strandline consists of a line of objects washed up on the beach and left stranded when the tide retreats. Walking the line can be a fun way to find all manner of saltwater, aquatic wildlife - or signs of such things. Although much of the line is likely to be made up of pieces of dead plant material and other detritus, other objects will soon be found with careful searching. This page helps with the identification of soft objects that might be found on the beach. This often includes jellyfish and related species, the eggs or egg cases of a variety of fish and shellfish and similar objects.


Soft wrackline objects can be heavily damaged by the rolling action of the surf and this can often render such objects unidentifiable for certain. Jellyfish in particular can be difficult but, overall size of the object can be useful, as well as color. Some objects are a mix of hard and soft, so you will find them included on the pages for both hard and soft objects.

  Buoy Barnacle     Dosima fascicularis

Although technically shellfish, Buoy Barnacles have rather soft shells and have a rubbery feel to them. They are typically marine creatures of deeper water, attaching themselves to floating objects out at sea. They may be found on pieces of driftwood or plastic that wash up on the beach from time to time. These small creatures may also produce their own 'float' and drift on ocean currents by hanging down from the surface and filtering water for food via their feathery legs.
Buoy Barnacle Buoy Barnacle Buoy Barnacle
Clustered on end of stick
Clustered on end of stick
Close-up of feathery legs

  Lion's Mane     Cyanea capillata

Whole animals may be up to 10 inches in diameter in our region, but specimens up to eight feet across with tentacles up to 200 feet long have been recorded in more northerly waters. Usually a light tan or pale brownish color with eight lobes to the main umbrella of jelly. Tentacles have usually broken off from beached specimens, leaving a simple, rounded disc of jelly.
Lion's Mane

  Skate Eggcase     Chondrichthyes

The egg cases (often called mermaid's purses) of several species of skate may be found washed up on the beach, but telling the different species apart can be difficult. Skate are flatfish that are related to sharks and many species of both groups produce egg cases. Eggs are laid in small 'envelopes' which have tendril-like corners that help the case to attach to seaweed on the sea floor. After eggs have hatched, the leathery, empty cases eventually break loose and often get washed up on the beach.
Skate Eggcase

  Atlantic Horseshoecrab Eggs     Limulus polyphemus

The tiny, pale blue eggs of Atlantic Horseshoecrabs wash up on the Delaware Bayshore beaches in great abundance during late May and early June. At times they form wavy lines of tiny, granular blobs along the beach as the tide recedes and attract vast numbers of birds that feed upon them. Eggs may often be found individually, but they are also occasionally found in clusters which may be up to an inch or more across.
Atlantic Horseshoecrab Eggs

  Mud Dog Whelk Eggs     Limulus polyphemus

Bundles of the pale, gelatinous egg masses of this small snail can often be found attached to pieces of wrackline detritus.
Mud Dog Whelk Eggs