Restoration Project

MBC Applied Aquatic - Downcoast Reef Point

Restoration Objective:

The aim of restoration was to reseed kelps where they had exhibited little or no recovery in order to improve biological and commercial outcomes.

Site Selection Criteria:

Transplant sites were selected where giant kelp was once present. Ideal transplant sites had many attachment points, no competing macroalgae and were in less than 13m of water.

Cause Of Decline:

Historically, beds of giant kelp (Macrocystis pyrifera) along the Orange County coastline were dense and covered much of the available rocky substrate from the shallow subtidal area down to 20m and deeper. These beds supported a diverse assortment of fish, invertebrates, and other plants, many of which were of significant interest to commercial and sport fisherman. The warm waters brought by the El Niño of 1982-1983 caused the loss of most giant kelp stands leaving only a few surviving patches along the Orange County shoreline. Additional stressors to kelp populations included urbanisation, low water quality, storms and overfishing.

Key Reasons For Decline:

Heatwave

Scientific Paper

Orange County Kelp Restoration Project

M.B.C.Applied Environmental Sciences, , p.93.

Organisation:

MBC Aquatic

Site Observations:

Observation Date

11th Sep 1988 – 27th Jul 1989

Action Summary:

Adult and juvenile Macrocystis pyrifera plants were transported from the donor site quickly, covered in a tarp and kept cool and moist. Juveniles were also grown in lab culture. Kelps were attached using rope sewn through the holdfast with needles. Adult and juvenile kelps were transplanted to 12 sites. Sites were monitored, maintained, and sometimes expanded with additional juvenile kelps over three years.

Project Outcomes:

By the final survey in September 1989 at Downcoast Reef Point 3 the kelp bed canopy had expanded slightly. However, plants were larger and more robust than previously, drift kelp was abundant and the substrate coverage had expanded upcoast and downcoast.

Key Reasons For Decline:

Heatwave

Area of Restoration (In Square Metres)

6,100

Indicator Data:

Indicator:

Ending Value:

Starting Value:

Adult Kelp Count

235100
Costings:
Cost Currency:USD

Observation Date

9th Aug 1988 – 27th Jul 1989

Action Summary:

Adult and juvenile Macrocystis pyrifera plants were transported from the donor site quickly, covered in a tarp and kept cool and moist. Juveniles were also grown in lab culture. Kelps were attached using rope sewn through the holdfast with needles. Adult and juvenile kelps were transplanted to 12 sites. Sites were monitored, maintained, and sometimes expanded with additional juvenile kelps over three years.

Project Outcomes:

During the final survey of Downcoast Reef Point 2, a dense surface canopy of approximately 1 acre and a subsurface coverage of almost 1.25 acres were noted. Adult (152), subadult (90), and juvenile (100) kelp plants were abundant. The bed appeared to be expanding, drift kelp was abundant, and while fish populations were large, evidence of kelp grazing was minimal.

Key Reasons For Decline:

Heatwave

Area of Restoration (In Square Metres)

8,100

Indicator Data:

Indicator:

Ending Value:

Starting Value:

Adult Kelp Count

342260
Costings:
Cost Currency:USD

Observation Date

14th Jul 1988 – 27th Sep 1989

Action Summary:

Adult and juvenile Macrocystis pyrifera plants were transported from the donor site quickly, covered in a tarp and kept cool and moist. Juveniles were also grown in lab culture. Kelps were attached using rope sewn through the holdfast with needles. Adult and juvenile kelps were transplanted to 12 sites. Sites were monitored, maintained, and sometimes expanded with additional juvenile kelps over three years.

Project Outcomes:

In Downcoast Reef Point 1, the kelp bed canopy had expanded slightly by the final survey in September 1989. However, plants were larger and more robust, drift kelp was abundant and the substrate coverage had expanded.

Key Reasons For Decline:

Heatwave

Area of Restoration (In Square Metres)

2,300

Indicator Data:

Indicator:

Ending Value:

Starting Value:

Adult Kelp Count

269180
Costings:
Cost Currency:USD