Restoration Project

University of Salento - Porto Cesareo

Restoration Objective:

The aim of this study was to assess the effectiveness of large-scale urchin culling in reducing herbivore pressure on disturbed benthic assemblages, and to assess the direction and time frame of assemblage recovery in barren grounds.

Site Selection Criteria:

The study was carried out in a marine protected area, and a site was chosen that was the most degraded (~60% barrens).

Key Reasons For Decline:

Multiple

Scientific Paper

Large-scale sea urchin culling drives the reduction of subtidal barren grounds in the Mediterranean Sea

G. Guarnieri, S. Bevilacqua, N. Figueras, L. Tamburello, S. Fraschetti, , Frontiers in Marine Science, Vol. 7, p.519.https://doi.org/10.3389/fmars.2020.00519

Organisation:

University of Salento

Site Observations:

Observation Date

1st Apr 2015 – 1st Jun 2018

Action Summary:

In a marine protected area, sea urchins were culled (via hammering) in spring 2015, over an area of 1.2 hectares at about 5m depth. The effects of sea urchin removal were monitored at regular intervals for a time span of 3 years and were compared with two control sites adjacent to the culling area.

Lessons Learned:

Recovery occurred even though sites were 60% urchin barren, however this was mainly driven by turf algae rather than by kelps.

Project Outcomes:

Culling reduced sea urchin populations compared to control sites (75% less), and this was consistently maintained throughout the experiment. Assemblages were different between control and culled sites, and the size of barrens was reduced in culling sites. This was driven by increased abundance of macroalgae, turf algae and filamentous algae and a reduction in invertebrates typical of barrens.

Key Reasons For Decline:

Multiple

Area of Restoration (In Square Metres)

6,000

Indicator Data:

Indicator:

Ending Value:

Starting Value:

Kelp Cover

15.6097561
%
8
%
Costings:
Cost Currency:USD

Observation Date

1st Apr 2015 – 1st Jun 2018

Action Summary:

In a marine protected area, sea urchins were culled (via hammering) in spring 2015, over an area of 1.2 hectares at about 5m depth. The effects of sea urchin removal were monitored at regular intervals for a time span of 3 years and were compared with two control sites adjacent to the culling area.

Lessons Learned:

Recovery occurred even though sites were 60% urchin barren, however this was mainly driven by turf algae rather than by kelps.

Project Outcomes:

Culling reduced sea urchin populations compared to control sites (75% less), and this was consistently maintained throughout the experiment. Assemblages were different between control and culled sites, and the size of barrens was reduced in culling sites. This was driven by increased abundance of macroalgae, turf algae and filamentous algae and a reduction in invertebrates typical of barrens.

Key Reasons For Decline:

Multiple

Area of Restoration (In Square Metres)

6,000

Indicator Data:

Indicator:

Ending Value:

Starting Value:

Kelp Cover

32.254
%
78.0487805
%
Costings:
Cost Currency:USD