Field Trips by Ellin Beltz

Fossil Localities - Humboldt Bay Area

Always respect personal property rights and the environment when fossil hunting.
For all ocean exposures, consult the tide tables and take all due precautions near the water.

Bear River Ridge

The north flank of the Bear River Ridge south of Ferndale has northward tilted Wildcat layers and a ridge crest of Yager and Cape Mendocino-False Cape shear zone rocks (Oscar Larson and Associates, 1978).

Rio Dell

No specific locality is cited for Rio Dell. It is possible that these fossils came from the Scotia Bluffs just east of Rio Dell but were catalogued to the town name or, they were collected from the point bar at Rio Dell or an outcrop exists on the point bar side of the river which contains these fossils.
Marco Mendez at Scotia Bluffs
Marco Mendez at Scotia Bluffs
2004 Ellin Beltz
  • Cockle shell Clinocardium meekianum
  • Mussel Myliticus californianius
  • Moon snails Nautica clausa
  • Sand dollars Scutellaster major
  • Neptune snail Neptunia smirnia
  • Gastropod Antiplanes pervasa
  • Littleneck clams Protothaca stayleyi
  • Whale barnacle Coronula sp.
  • Crab claw (sp ?)
  • Clam Macoma addicotti
  • Razor clam Siliqua oregonensa

Scotia Bluffs

In addition to the mollusks and sand dollars commonly found, the Scotia Bluffs are reported to have produced some plants, turtles, starfish and agatized whale bone (Miller, 1999). Approach the bluffs from an access point on the southeast side of the Rio Dell/Scotia bridge. Walk along the railroad tracks (abandoned) under Highway 101 to the Bluffs. There is no automobile access beyond the parking lot that belongs to Pacific Lumber. Check in with their guard. If you're lucky, it's the gentleman who knows more about the local fossils than just about anyone else in Humboldt. Park your car with him or his coworkers.

Be sure to take a knapsack or backpack as this is a hike out to the bluffs. Walk along the tracks until you can see the railroad bridge. This is where the big pelecypod mollusks (look like the Shell Oil insignia) are found in mudstone or eroding out. they can be up to about 9 inches across if complete.

Cross the railroad bridge with caution to an exposure of sandstone or sand. This is the area which produces sand dollars and concretions which contain mollusks and other fossils.

Print out a topo map for Scotia Bluffs from

Scotia gage
The last 30 days river gage at Scotia, elevation 160 feet above mean sea level.
Don't go to the Bluffs if the river is in flood stage.


No specific location or species was given for the fossil whale bone found at Bridgeville, but a local collector says it was on private land well away from the river.

Centerville Beach

Hookton/Carlotta, Scotia Bluffs and Rio Dell Formations coarsen upward and show filling of the basin over time (Stanley, 1995). Access Centerville Beach by driving 5 miles west from Ferndale along Centerville Beach road. Walk south along the beach only at low tide to the north dipping clay layer which contains the Giant Pacific Scallop fossils (Pectin caurinus).

The cross on the hill is the historical marker for the wreck of the Northerner. The California State Landmark number 173 records, "On January 6, 1860 the steamer Northerner, northward bound from San Francisco, struck a hidden rock two miles off Cape Mendocino, and from there drifted to the Centerville Beach. Thirty-three passengers and 32 crew members were saved - the cross was erected by the Ferndale Parlor No. 93, N.D.G.W., in memory of the 17 passengers and 21 crew members who lost their lives in this disaster."

Blue Lake

No specific location was given for the mussels, Myliticus condoni, with "Blue Lake" as a locality.


No specific location was given for the sea urchin, Strongylocentrotus sp., with "Eureka" as a locality.

Crannell Junction

East of 101 on Crannell Road north of Arcata and South of Trinidad. Several papers mention fossils taken from a bluff in Crannell apparently connected with the now-abandoned railroad tracks.

Pilot Point

Pilot Point Coquina
Pilot Point Coquina
2004 Ellin Beltz
Approximately 23 miles north of HSU near Moonstone Beach an exposure of fossil coquina on a steep and eroding cliff is productive of intact gastropods, other mollusks, sand dollars, huge barnacles, and the occasional mammal fossil including seal teeth. You can find fossils in the sand below the cliff and in the cliff face itself. There is little to no cement between the fossils; all but the gastropods require instant hardening or they do not survive removal.

Patrick's Point State Park

You can observe living invertebrates in tide pools at Palmer's Point and Agate Beach or look for agates at the latter. Look against the light for the clear or nearly clear agates which are polished by the constant movement of the waves and sand.

Take another field trip... Chicago . Hawai'i . Humboldt County . Illinois . Wyoming
Visit my Nifty Links...
Visit my home page Ellin Beltz -
Updated: January 10, 2008
Valid HTML 4.01!