Restoration Project

Shanghai Ocean University - Maocaotan

Restoration Objective:

This study conducted breeding of S. vachellianum from wild populations in order to produce seedlings on artificial reeds, and aid restoration of natural S. vachellianum beds.

Site Selection Criteria:

Selected sites were areas that had previously been assessed to have a moderately degraded S. vachellianum ecosystem.

Cause Of Decline:

Approximately 12,000km2 of seaweed beds was lost worldwide between 1985 and 1995. In addition, nine species of Fucales disappeared in the Albères Coast (France, NW Mediterranean) from the end of 19th century to 2005. Most of these losses probably occurred due to various human activities (trawling, anchoring, bomb blasts) and intensive grazing by herbivorous animals. Assessment of the health of the S. vachellianum ecosystem in Gouqi Island in 2011 indicated a moderate level of degradation.

Key Reasons For Decline:

Overgrazing

Scientific Paper

Studies on breeding of Sargassum vachellianum on artificial reefs in Gouqi Island, China

Z.Y. Chai, Y.Z. Huo, Q. He, X.W. Huang, X.P. Jiang, P.M. He, , Aquaculture, Vol. 424.https://doi.org/10.1016/j.aquaculture.2013.12.038

Organisation:

Shanghai Ocean University

Site Observations:

Observation Date

1st Jul 2012 – 1st Aug 2013

Action Summary:

S. vachellianum was collected and bred to produce fertilised eggs. Eggs were then sprayed onto breeding boards and cultured into seedlings. Breeding boards with seedlings attached were then installed as artificial reefs at two sites, one with high and one with low current.

Lessons Learned:

Survival rates of seedlings on artificial reefs may be low as they were transplanted as very small plants (~5mm).

Project Outcomes:

After being cultivated for 45 days in the open sea, the average length and density of seedlings on artificial reefs at Site A and Site B were 31.85 ± 0.62 and 41.31 ± 1.39 mm, 4.70 ± 1.40 and 5.19 ± 2.65 seedlings dm−2 , respectively. After a year, the length of the plants on artificial algal reefs in the Gouqi Island coast reached up to 15.51±3.42 cm. All the results indicated that large scale artificial breeding of S. vachellianum using artificial reefs was feasible

Key Reasons For Decline:

Overgrazing

Indicator Data:

Indicator:

Ending Value:

Starting Value:

Juvenile Kelp Density

0.00595
/ m2
0.18
/ m2
Transplant Info:
Adherence Method:Attached to Artificial Reef
Life Stage:Juveniles
Costings:
Cost Currency:USD

Observation Date

1st Jul 2012 – 1st Aug 2013

Action Summary:

S. vachellianum was collected and bred to produce fertilised eggs. Eggs were then sprayed onto breeding boards and cultured into seedlings. Breeding boards with seedlings attached were then installed as artificial reefs at two sites, one with high and one with low current.

Lessons Learned:

Survival rates of seedlings on artificial reefs may be low as they were transplanted as very small plants (~5mm).

Project Outcomes:

After being cultivated for 45 days in the open sea, the average length and density of seedlings on artificial reefs at Site A and Site B were 31.85 ± 0.62 and 41.31 ± 1.39 mm, 4.70 ± 1.40 and 5.19 ± 2.65 seedlings dm−2 , respectively. After a year, the length of the plants on artificial algal reefs in the Gouqi Island coast reached up to 15.51±3.42 cm. All the results indicated that large scale artificial breeding of S. vachellianum using artificial reefs was feasible

Key Reasons For Decline:

Overgrazing

Indicator Data:

Indicator:

Ending Value:

Starting Value:

Juvenile Kelp Density

0.00452
/ m2
0.18
/ m2
Transplant Info:
Adherence Method:Attached to Artificial Reef
Life Stage:Juveniles
Costings:
Cost Currency:USD