University of California institute of Marine Science - Point Loma

Restoration Project

University of California institute of Marine Science - Point Loma

Restoration Objective:

The objective of this study was to determine the effectiveness of liming on urchin control, and to test possible harmful side effects to other species.

Site Selection Criteria:

Sites were selected that had previous kelp cover, close proximity to remnant kelp beds and high urchin densities.

Key Reasons For Decline:

Ocean warming

Scientific Paper

Kelp Habitat Improvement Project Final Report 1 Dec., 1963

W. North

Site Observations:

Observation Date

15th Jun 1981 – 15th Jun 1983

Action Summary:

The harvest company Kelco deployed divers to use hammers to destroy urchins over 50ha at south Point Loma in 1981.

Lessons Learned:

Kelp beds increased in cover following urchin culls.

Project Outcomes:

30 ha of Macrocystis canopy developed at south Point Loma by summer of 1982. The remaining 20 ha recruited Macrocystis during 1982 and was expected to produce canopy in 1983.

The Macrocystis kelp forests of Palos Verdes (Los Angeles) and Point Loma (San Diego) are threatened by water pollution, sea urchin grazing and other factors.

Key Reasons For Decline:

Multiple

Area of Restoration (Ha)

50

Indicator Data:

Indicator:

Ending Value:

Starting Value:

Presence / Absence of Kelp

Observation Date

16th Mar 1962 – 31st Aug 1963

Action Summary:

2 tonnes of quicklime was distributed over an area of 2 acres, at a dosage of 0.05 pounds/square foot. In a second treatment, 2 pounds of quicklime at a dosage of 0.01 lbs/square foot was distributed in an area of 200 x 2000 ft.

Lessons Learned:

The Paolo Verdes site had most successful regeneration due to its proximity to a healthy Macrocystis bed.

Project Outcomes:

Blooms of Ectocarpus and Licmophora regenerated.

Key Reasons For Decline:

Ocean warming

Area of Restoration (Ha)

6.4

Indicator Data:

Indicator:

Ending Value:

Starting Value:

Juvenile Kelp Density

20.0000
/ m2
0.0000
/ m2

Observation Date

4th Jun 1962 – 31st Aug 1963

Action Summary:

2 tonnes of quicklime was distributed over an area of 800 x 100 ft in June, giving a dosage of 0.05 pounds per square foot. In August, another 2 tonnes of quicklime was distributed in the northern area of the site.

Lessons Learned:

The Paolo Verdes site had most successful regeneration due to its proximity to a healthy Macrocystis bed.

Project Outcomes:

Macrocystis was first observed in August. A covering of turf algae and diatoms also appeared (Ectocarpus and Licmophora).

Key Reasons For Decline:

Ocean warming

Area of Restoration (Ha)

0.7

Indicator Data:

Indicator:

Ending Value:

Starting Value:

Juvenile Kelp Density

0.1000
/ m2
0.0000
/ m2