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EBSA overview  |  Delineation |  Summary of description updates  | Revised description

 

EBSA overview

The Namaqua Fossil Forest is a small (2 km2) seabed outcrop composed of fossilized yellowwood trees at 136-140 m depth, approximately 30 km offshore on the west coast of South Africa. The fossilized tree trunks form outcrops of laterally extensive slabs of rock of dimensions >5 x <1 x <0.5 m, which have been colonized by fragile, habitat-forming scleractinian corals. Based on regional side scan sonar interpretations, this feature is believed to be unique to the area; further, a new species of yellowwood tree was described from this fossil forest. The EBSA thus encompasses a unique feature with substantial structural complexity that is highly vulnerable to benthic impacts.

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Delineation

Open or collapse the legend as a sidebar by clicking the icon in the top left corner of the map. In the legend you can turn on/off the old/new extents of the EBSA. You can zoom in/out using the mouse or the +/- buttons on the map, and click on the features for more information.

 

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Summary of updates and revisions to the EBSA description

1 new reference added; relatively minor editing of the previous description. No further research has been conducted in the area.

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Revised EBSA description

NOTE: Read this here, or download the Word document on the right sidebar.

 

General Information

Summary

The Namaqua Fossil Forest is a small (2 km2) seabed outcrop composed of fossilized yellowwood trees in the 136-140 m depth range, approximately 30 km offshore on the west coast of South Africa. The fossilized tree trunks have been colonized by fragile, habitat-forming scleractinian corals, confirmed by images from submersible surveys. The outcrops are composed of laterally extensive slabs of rock of dimensions >5 x <1 x <0.5 m. Based on regional side scan sonar interpretations, the outcrop is believed to be unique to the area. The site is un-mined although it may fall within a current diamond mining lease area. In summary, the Namaqua fossil forest is a highly unique feature with substantial structural complexity that is highly vulnerable to benthic impacts.

 

Introduction of the area

The Namaqua Fossil Forest is a small (2 km2) seabed outcrop composed of fossilized yellowwood trees in the 136-140 m depth range on the middle shelf off the Namaqualand coast in South Africa. The area is approximately 30 km offshore between Port Nolloth and Kleinsee. Fossilized tree trunks have been colonized by fragile, habitat-forming scleractinian corals. Based on regional side scan sonar interpretations, the outcrop is believed to be unique to the area. Fragments of fossil tree trunks were, however, recovered from mined areas about 60 km away from this site but those fragments are no longer in-situ and were removed from the seabed. The site is within the productive southern Benguela ecosystem but there is no information on local-scale oceanography for this area.

 

Description of the location

EBSA Region

South-Eastern Atlantic

 

Description of location

This area occurs on the middle shelf in the 136-140 m depth range off the Namaqualand coast in South Africa. It is within the EEZ of South Africa.

 

Geo-Location

SEA_41_EBSA.geojson

 

Area Details

Feature description of the area

This is a benthic feature composed of laterally extensive slabs of rock of lengths greater than 5 m and usually less than 1 m in width. The fossilized wood is reported to extend to 0.5 m in height although the geology of the broader area includes erosional-resistant, high relief areas (up to 5 m) (Stevenson and Bamford 2003). The lithology has not been sampled directly, but is believed to be claystone. According to in-situ observations during submersible surveys, the fossilized wood has been colonized by scleractinian corals. Apparently, no biological sampling has been conducted previously at the site, with research activities being focused rather on the geology of the area. Two species of fossil wood were documented in the area, both from the Podocarpidae family; Podocarpus jago and P. umzambense, the former being a species described from this site (Bamford & Stevenson, 2002).

 

Feature conditions and future outlook of the proposed area

The in-situ surveys of this unique site showed large, intact, fossilized tree trunks that support habitat-building corals. The site is considered to be unmined although it may fall within a current diamond mining lease area, the future of which is uncertain. Mining is not currently taking place. There is no known future research planned for the area.

 

References

Bamford, M.K., Stevenson, I.R. 2002. A submerged Late Cretaceous podocarpus forest, west coast, South Africa. South African Journal of Science, 98: 181-185.

FAO. 2006. Management of Demersal Fisheries Resources of the Southern Indian Ocean. FAO Fisheries Circular No. 1020 FAO Rome 2006.

FAO. 2009. Annex F of the Report of the Technical Consultation on International Guidelines for the Management of Deepsea Fisheries in the High Seas. Rome, 4–8 February and 25-29 August 2008.

Lagabrielle E. 2009. Preliminary report: National Pelagic Bioregionalisation of South Africa. Cape Town: South African National Biodiversity Institute.

Rogers A.D., Clark M.R, Hall-Spencer K.M and Gjerde K.M. 2008. The Science behind the Guidelines: A Scientific Guide to the FAO Draft International Guidelines (December 2007) For the Management of Deep-Sea Fisheries in the High Seas and Examples of How the Guidelines May Be Practically Implemented. IUCN, Switzerland.

Sink K, Holness S, Harris L, Majiedt P, Atkinson L, Robinson T, Kirkman S, Hutchings L, Leslie R, Lamberth S, Kerwath S, von der Heyden S, Lombard A, Attwood C, Branch G, Fairweather T, Taljaard S, Weerts S, Cowley P, Awad A, Halpern B, Grantham H, Wolf T. 2012a. National Biodiversity Assessment 2011: Technical Report. Volume 4: Marine and Coastal Component. South African National Biodiversity Institute, Pretoria.

Sink KJ, Wilkinson S, Atkinson LJ, Sims PF, Leslie RW, Attwood CG. 2012b. The potential impacts of South Africa’s demersal hake trawl fishery on benthic habitats: historical perspectives, spatial analyses, current review and potential management actions. Unpublished report. Cape Town: South African National Biodiversity Institute.

Stevenson R and Bamford MK. 2003. Submersible-based observations of in-situ fossil tree trunks in Late Cretaceous seafloor outcrops, Orange Basin, western offshore, South Africa. South African Journal of Geology 106: 315-326.

 

Other relevant website address or attached documents

Additional_figures_SEA_41.pdf (/api/v2013/documents/D6939B75-054E-C649-2AD3-4F371F6A9157/attachments/Additional_figures_SEA_41.pdf)

SEA_41_EBSA-GIS shapefile.zip (/api/v2013/documents/D6939B75-054E-C649-2AD3-4F371F6A9157/attachments/SEA_41_EBSA-GIS%20shapefile.zip)

 

Status of submission

Areas described as meeting EBSA criteria that were considered by the Conference of the Parties

 

COP Decision

dec-COP-12-DEC-22

 

Assessment of the area against CBD EBSA criteria

C1: Uniqueness or rarity High

Justification

Based on regional side-scan sonar interpretations covering more than 2300 km2 between the area offshore of Chamais Bay in Namibia and offshore of the Buffels river in South Africa, there are no other known in situ fossilized yellowwood forests in the region (Stevenson and Bamford 2003). Further, the published images of in situ habitat-building corals prove this site to be one of the few confirmed localities of in situ cold-water corals in the region (Stevenson and Bamford 2003). Other fragments of fossil tree trunks were recovered from test-mine areas north-west of the area that meets the EBSA criteria, but these were buried fragments (Stevenson and Bamford 2003).

C2: Special importance for life-history stages of species No information

Justification

Little is known about the biodiversity and ecology of this small area (Sink et al., 2012a).

C3: Importance for threatened, endangered or declining species and/or habitats No information

Justification

Little is known about the biodiversity and ecology of this small area (Sink et al., 2012a).

C4: Vulnerability, fragility, sensitivity, or slow recovery High

Justification

The fossilized wood and accompanying cold-water coral colonies are considered vulnerable to any activities that could impact on the seabed (FAO 2006, Rogers et al., 2008, FAO 2009, Sink et al., 2012a,b).

C5: Biological productivity Medium

Justification

This small localized area is unlikely to be more or less productive than the area surrounding it, but it does occur within the productive Southern Benguela ecosystem (Lagabrille 2009, Sink et al., 2012a).

C6: Biological diversity No information

Justification

Little is known about the biodiversity and ecology of this small area (Sink et al., 2012a).

C7: Naturalness No information

Justification

It is unknown whether this area has been impacted by human activities. The area has some overlap with a diamond mining lease area but apparently, it has not yet been mined (Leslie Roos, De Beers, South Africa pers. comm.). There is currently no mining within this offshore diamond mining lease although the future of mining in the area is uncertain (Sink et al., 2011, 2012a). There is no known fishing activity within the site.

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