3/16/24 Morning Biodredge

Biodredge Report

Station: BioDredge / Rock Pile
Date: 3/16/2024, 9:59 am
Conditions: sunny, lt wind, 66°F
Latitude: 33° 40' 27" to 33° 40' 35" N
Longitude: 118° 13' 43" to 118° 13' 23" W

Sediment Desc: Gravel to cobble sized rocks = mostly 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.

 

  • Articulated Coraline Algae.
  • Turkish Towel Kelp
  • Turkish Towel Kelp
  • Kelp floating on the ocean's surface often traps trash.
  • Kelp anchors itself onto the seafloor by wrapping it's roots around a rock - called a holdfast. Diverse ecosystems form on these rocks. This one contains red kelp, red encrusting algae, and cup coral.
  • The black blob on the top of this holdfast is actually a dark green algae. Also visible is red encrusting algae. Note the bedding on the left side of the rock.
  • This holdfast has more red kelp and red encrusting algae, and some feather hydroids.
  • Cup Coral
  • Reticulated Brittle Star
  • Reticulated Brittle Star
  • Sea Cucumber
  • Bat Star
  • Sand Stars
  • Heart Urchins bury into the sand for protection from predators.
  • Heart Urchin (top)
  • Heart Urchin (bottom)
  • Purple Urchin
  • Purple Urchin
  • Red Urchin
  • Red Urchin
  • White Urchins
  • White Urchins
  • Frog Snail (Top)
  • Frog Snail (bottom)
  • Chiton
  • Kellet's Whelk (top)
  • Kellet's Whelk (bottom)
  • Many organisms will attach themselves to other ogranism. There is a small barnacle attached to this Kellet's Whelk.
  • This Kellet's Whelk has red encrusting algae and articulated coraline algae attached to it's shell.
  • Polychaete Worm