Restoration Project

California Department of Fish and Wildlife - Carlsbad

Restoration Objective:

The purpose of this reef was to (1) provide shelter, forage, nesting and nursery areas for fishes and invertebrates; (2) offer rocky substrate for the attachment and growth of marine animals and plants, particularly giant kelp (Macrocystis sp.); and (3) provide study sites to investigate the effect of reef location, depth, relief, and rock size on the development of associated biotic communities.

Cause Of Decline:

Macrocystis pyrifera beds along the southern California coast were relatively stable prior to 1940. Declines were first reported in 1945 in areas nearest major sewage outfalls. This deterioration progressively affected beds at increasing distances from the outfalls, leaving small patches. Deterioration of kelp accelerated when an influx of warm oceanic water persisted off California from 1957-1959.

Key Reasons For Decline:


Scientific Paper

1997 biological surveys of four Southern California artificial reefs: Oceanside# 2. and Mission Bay Park

J. Kashiwada, , Carlsbad, Pacific Beach.


California Department of Fish and Wildlife

Site Observations:

Observation Date

6th Jun 1991 – 1st Feb 1997

Action Summary:

Carlsbad Artificial Reef (CAR) was constructed in 1999 using 10,000 tons of quarry rock. CAR is shallower than other reefs and has 12 single modules arranged in 3 depth strata.

Lessons Learned:

This artificial reef used 10,000 tonnes of quarry rock to create artificial reefs, however they did not effectively enhance macroalgae cover at most sites.

Project Outcomes:

Macroalgae were relatively scarce on CAR which had abundant giant kelp two years ago.

Key Reasons For Decline:


Indicator Data:


Ending Value:

Starting Value:

Adult Kelp Density

/ m2
/ m2
Cost Currency:USD