North Coast diving is all about catching dinner, particularly abalone. I can poetically describe the beauty of our northern reefs and their abundance of colorful marine life, yet few will listen. If you can freedive to 30 feet you can bag your limit of abalone off any rocky beach in Sonoma and Mendocino Counties. In my search for the best abalone sites in Sonoma County the area between the Gerstle Cove and Stewarts Point State Marine Reserves is near the top of the list, and Fisk Mill Cove is a great place to check out.

Shearwater TERN
The northern portion of Fisk Mill Cove is within the Stewarts Point State Marine Conservation Area and no game may be taken. However, the southern portion of the cove offers plenty of unimproved parking areas with access to great abalone diving. All involve an easy to moderate level hike followed by an easy to moderate scamper down a bluff face.
One of my favorite entries is called South Cove. Here there is a substantial finger of rock that creates a very protected entry, even with moderate surf. The inshore, shallow reef holds a large number of 7- to 8-inch size abalone. If you are comfortable freediving 15 to 20 feet, try the area inshore of the furthest offshore wash rock to the left of the entry. For bigger abalone dive offshore and north of the wash rock in 30 to 40 feet of water for 9- to 9.5-inch size abalone. The area north of the cove is also a great place to dive on a rocky bottom filled with deep cracks and crevices. If taking game be sure you do not wander into the reserve that begins in the next cove north.
The area south of South Cove to Stump Beach has many dive spots to choose from. All involve a bit longer hike, and a bit more difficult scamper down the bluff, and great abalone diving just offshore. These sites are less well protected than South Cove, and should only be dived on calm days.
In their single-minded search for game, divers often over look the beauty of the reef. These reefs are dotted with steep-sided pinnacles and rock bottoms covered with huge boulders along with underwater caves and arches. The shallow rocks are covered with palm and bull kelp, but the deeper reefs are colorful with many large anemones and encrusting sponges. This area has quite a few rockfish, kelpfish and a few lingcod. Freedivers can easily enter at any of the spots mentioned here. Scuba divers will find that South Cove and the northern part of Fisk Mill Cove offer better entries.
In August of 2011 an extremely strong red tide overcame a great deal of marine life along the Sonoma Coast, and thousands of abalone, sea stars and other invertebrates and fish washed up dead. This prompted the Dept. of Fish and Wildlife to close the abalone fishery for the remainder of the season. When it reopened in 2012 it appeared (from my observations, not scientific data) that the red tide selectively killed larger abalone and those in deeper water. After several trips this year it seems that the abalone are back! The deeper reefs are currently full of 8.5- to 9.5-inch abalone, and the shallow reefs are chock full of 5- to 7.5-inch abalone. Seems everything in the sea has its cycle, and the abalone population seems to be cycling back to normal. (Note: it takes many years for an abalone to reach the legal, 7-inch size. The increase in abundance this year must be due to movement of abalone to populate optimal areas.)
Scuba is not permitted when taking abalone, so remember, breath-hold diving only. Abalone must be 7 inches at their widest, and divers must possess a fishing license, abalone tags and punch card, and legal abalone iron and measuring device. Abalones must be tagged immediately after coming ashore or boarding a vessel. Visit for the complete set of rules. 
Location: In the northern portion of Salt Point State Park, Sonoma County. South Cove is at mile marker SON 42.36. There are numerous turnouts between SON 39.89 and 42.15. The improved parking area at mile marker SON 42.63 is currently closed. You may also park in the large, dirt lot at SON 43.06 *Note: this area is within the reserve.
Access and Facilities: Free parking off Hwy. 1 at the mile markers listed above. No facilities. The parking lot with toilets at the northern portion of Fisk Mill Cove is currently closed and chained off due to budget issues.
Depth: 10 to 40 feet 
Visibility: 5 to 15 feet 
Skill Level: Intermediate on calm days, advanced when the wind and surf are moderate, avoid on rough days.
Hunting: Great abalone hunting, fair spearfishing for rockfish and lingcod. The southern boundary of the Stewarts Point State Marine Reserve is between the two parking areas that are west and south of mile marker SON 42.63. Make sure you are well south of the boundary before taking game. The southern portion of Fisk Mill Cove is within the Salt Point State Marine Conservation Area where only abalone and finfish may be taken.
Photography: Good macro photography when the visibility is good.
Hazards: Watch for thick kelp in late summer and fall, and sleeper waves at any time. This area experiences strong rip and tidal currents. Remember to swim perpendicular to the rip until it weakens before attempting to swim back to shore. 
California Diving News