Biological Dredge

Station: Rock Pile
Date: 3/17/2018, 1:56 PM
Conditions: 57°C, sunny, no clouds, winds WSW 13 mph
Latitude: 33° 40' 34" to 33° 40' 30" N
Longitude: 118° 13' 35" to 118° 13' 23" W

Sediment Desc: Gravel to boulder sized rocks (siltstones)

Kelp does not put down roots in the sediments on the seafloor. Instead, it anchors itself onto rocks. Many organisms make these rocks their own. The area on the San Pedro shelf called the "Rock Pile" is where the coastline used to be 10,000 years ago. As the planet warmed and the ice sheets melted, sealevels rose, covering this rocky coastline with seawater.

Below are some pictures of the organisms we collected during this biodredge. All creatures were returned to the ocean.

  • Kelp will wrap it's roots around any rock - in this case, a chunk of asphalt formed from a seep on the seafloor.
  • Holdfast
  • Holdfast
  • Turkish Towel
  • Red Sponge
  • Sand Shrimp
  • Sand Dollar
  • Reticulated Brittle Star
  • Reticulated Brittle Star
  • Sand Star (top)
  • Sand Star (bottom)
  • Sand Star (top)
  • Sand Star (bottom)
  • Heart Urchin (top)
  • Heart Urchin (bottom)
  • Heart Urchin
  • White Urchins (top)
  •  Heart Urchins (bottom)
  • Chiton
  • Kellet's Whelk (top)
  • Kellet's Whelk (bottom)
  • Salp
  • Salp