Also see media release, "Deputy Minister visits Greater St Lucia Wetland Park to
inspect Jolly Rubino scene" (16 September 2002)

The recent grounding of the ship Jolly Rubino on the coast of the Greater St Lucia Wetland Park (GSLWP) has to date resulted in approximately 450 tons of oil being discharged into the close inshore and surf-zone waters. The stricken ship has on board over 1000 tons more oil, and the possibility of further spillage poses a further threat to the marine and estuarine ecosystems of the GSLWP. The potential for environmental damage is particularly high in that the area has high biodiversity value, contains sensitive ecosystems and is rich in natural resources. These attributes, combined with its spectacular scenic beauty, justified the GSLWP's proclamation as a World Heritage Site.

Given the special sensitivity of the St Lucia lake system, actions taken include precautionary measures both to mitigate damage incurred and as well as to prevent potential impacts. The salvage operation is aimed at towing the vessel out to sea and/or removing hazardous cargo. The preventative and rehabilitation environmental management plan being implemented was comprehensive bringing together the specialist skills of KZN Wildlife, DEAT and the Wetlands Authority. The environmental measures include the sealing the estuarine systems, monitoring wildlife, dispersing oil at sea, and shoreline oil absorption and removal. Once the danger of further oil spillage is past, and preventative measures are no longer needed, clean-up and rehabilitation plans will be implemented.

An urgent judgment call had been taken to build berms in environmental sensitive areas had had to be made to protect sensitive wetland areas including mangrove forests, swamp forests, prawn nursery grounds, fish nurseries, hippo, crocs and birdlife including unique breeding colonies such as pelicans. Concern has also been expressed about humpback whales which are currently migrating southwards through the Wetlands Park.

Management of the situation can be divided into three phases:

• Preventative measures.
• Monitoring and mitigation.
• Clean-up and rehabilitation.

PHASE 1: PREVENTATIVE MEASURES

A priority action has been the closure of estuaries to prevent oil pollution.

• The St Lucia Estuary has been closed by building a 2km sand berm.
• The Umzumduze River has been screened with a floating boom to protect swamp forest from oil.
• Key mangrove inlets in the Umfolozi estuary are being protected using purpose designed floating booms.

The salvage operation is attempting to tow the vessel out to sea and/or remove hazardous cargo including oils and diesel.

PHASE 2: MONITORING AND MITIGATION

The following monitoring is underway, and mitigation plans are to be implemented:

Monitoring

• Pollution monitoring -- shoreline, offshore and estuaries.
• Monitoring of bird populations in estuary mouth (daily) -- check for fouling.
• Monitor hump-back whales for distress.

Management interventions:

• Decontamination of oiled wildlife:
  • bird rehabilitation and cleaning station established at St Lucia; and
  • oiled crocodiles to be transferred to crocodile centre at St Lucia.
• Maintenance of estuary dynamics in manipulated closed mouths, by implementing breaching procedure to allow seawater flushing.
• Use of dispersant on oil offshore.
• Use of absorbent material to mop up oil in intertidal.
• Mechanical dispersal of oil, by Kuswag 1.
• If high probability of oiling in the Umfolozi mouth area (sandflats) -- employ “scaring” methods for birds.
• Trapping and translocation of crocodiles if oil pollution imminent.

PHASE 3: ECOSYSTEMS CLEAN-UP AND REHABILITATION

Once the threat of oil pollution is over, detailed plans for the following clean-up and rehabilitation operations will be implemented:

• Clean-up of oil deposits -- shoreline and estuaries.
• Removal of sand berms in Umfolozi and St Lucia estuary mouths.
• Remove oil aggregated absorbant from shoreline.
• Rehabilitation of roads and access ramps damaged during process.
• Release of rescued wildlife (crocodiles and birds).
• Ongoing wildlife and ecosystem monitoring programme to track recovery.

These measures are necessary World Heritage Sites are chosen for their universal values. The Greater St Lucia Wetland Park qualified for three of the possible 4 universal natural values. The Wetlands remain one of the few places on earth were once can see the oldest and largest sea mammal the whale next to the oldest land mammal, the rhino, and biggest land mammal, the elephant.

The South African government banned mining and committed itself to generate growth and jobs through an investment drive that would at the same time conserve the fragile environment of the dunes the rest of the park. The Wetlands Authority has been established to ensure this commitment is met. To date it has succeeded in incorporating 16 different parcels of land into the Greater St Lucia Wetland Park making a 220km long, almost 300 000ha protected area. The Wetlands Authority is now concentrating on ensuring that the Park operates as an integrated ecological unit and is managed in line with international best practice. The Park includes Kosi Bay, Lake Sibaya, Sodwana Bay, uMkhuzi, Cape Vidal, Lake St Lucia and Maphelane.

Contact (082) 788-3000 -- Andrew Zaloumis, Acting CEO Greater St Lucia Wetland Park, or (082) 459-1917, Jean Harris, Regional Ecologist Marine KZN Wildlife.

POTENTIAL OILING OF MARINE & ESTUARINE SYSTEMS OF THE GREATER ST LUCIA WETLAND PARK: ECOLOGICAL SENSITIVITY, PREVENTATIVE MEASURES, AND REHABILITATION

16 September 2002

The grounding of the ship Jolly Rubino on the coast of the Greater St Lucia Wetland Park (GSLWP) on Thursday 12 September 2002 has to date resulted in approximately 50 tons of oil being discharged into the close inshore and surf-zone waters. Furthermore, the ship still has on board over 1000 tons more oil. This poses a significant threat to the marine and estuarine ecosystems of the GSLWP. The potential for environmental damage is particularly high in that the area has high biodiversity value, contains sensitive ecosystems and is rich in natural resources. These attributes, combined with its spectacular scenic beauty, were internationally recognised when it was proclaimed a World Heritage Site.

The ship is aground about 200m off the shore-line just north of the Cape St Lucia lighthouse, and 12km south of Mhapelane and the St Lucia lake estuary mouth. During the first 48 hours of its grounding the wind was south-westerly and this pushed the oil plume northwards. During this period the rocks immediately inshore were relatively heavily oiled, while further north towards the estuary dispersed light oiling was evident on the beaches and in the surf as far north as the Umfolozi river mouth. Fortunately the oiled rocks are low-lying beach-rock which are frequently inundated by sand naturally, and therefore do not support rich established biological communities. The intertidal rock ledges in the area, which support dense mussel beds and rich diversity, were largely unaffected during this period, partly due to the neap tides resulting in their remaining uncovered. An oil line on the high water mark of the sand shores was evident for about 5 kilometers south of the ship. After Saturday the wind swung to the north-east and the oil plume moved southwards and offshore. Light oiling on the shoreline is now evident for about 5 km south of the ship. The Umfolozi estuary and the St Lucia estuary have so far remained clear of any significant oil pollution. However, strong south-westerly winds are expected later this week, and this combined with the approaching spring tide, presents a potential threat to the estuarine systems if either the spilled oil or additional oil is pushed back to the area.

Given the sensitivity of the St Lucia lake system precautionary measures have been taken to prevent/mitigate potential damage. The salvage operation is aimed at removing the vessel out to sea and/or removing hazardous cargo. The environmental measures are currently focussed on sealing the estuarine systems, dispersing oil at sea, and shoreline oil absorb/aggregation. These measures should stay in force until the potential threat of oil pollution is removed completely.

This report outlines the:

• Ecological systems vulnerable to oil pollution.
• Preventative measures adopted.
• Rehabilitation plans.

ECOLOGICAL SENSITIVITY

This section outlines the key marine and estuarine systems sensitive to and threatened by the oil pollution. It identifies the habitats and species that are most susceptible to oil pollution, and the specific areas that are considered to be within the radius of impact of the potential oil pollution event.

1. Wetlands (Umfolozi/Umzunduze and St Lucia systems)

There are four main wetland areas of concern with regard to potential impacts from oiling (see Figure 1):

1.1 St Lucia lake and estuary system

The St Lucia estuarine lake system is the largest estuarine system in Africa. The system covers an area of approximately 300 square kilometres, comprising a series of three shallow compartments connected to the sea by a meandering channel 21km long, known as the Narrows. Four rivers feed the lake and one enters the system in the Narrows. It harbours a wide diversity of wetland habitats, and is an important migratory bird destination. In addition to this high biodiversity it is an important source of natural resources for rural communities surrounding the lake (e.g. reeds).

Key sensitive habitats, species and features:

• Intertidal mud and sand-flats.
• Reed swamps.
• Mangrove forests.
• Swamp forests.
• Important penaeid prawn nursery ground.
• Significant fish nursery (82 estuarine dependant species recorded).
• Birdlife, and breeding colonies (e.g. pelicans).
• Large Hippopotamous population (704 hippos counted in 2002).
• Important breeding populations of crocodiles.
• Recreational fishing important for local industries.

1.2 Umfolozi -- Umzunduze estuary

The Umfolozi river is joined near its mouth by the Umzumduze River. This confluence forms a wide area of shallows and sand-flats, which is fringed to the west by a mangrove forest. Currently the northern part forms a “blind estuary” area that is separated from the St Lucia estuary mouth by a sandbar. This estuary is frequented by large numbers of waders and other birds, as well as crocodiles and hippos.

Key sensitive habitats and species:

• Sand-flats (an important roosting and feeding area of coastal birds, particularly waders).
• Mangrove forest (with a channel leading off the blind estuary).
• Water-birds (e.g. about 360 birds, including 11 species of waders, counted on 16 September 2002).
• Crocodiles (feeding in the shallows and basking on the sand-banks).

1.3 Umzunduze River

The Umzunduze river is tidal for approximately 14 kilometers. It supports estuarine fish, which are the basis of a subsistence fishery for the adjacent Sokhulu community. A special and sensitive feature of this river is the presence of a Barringtonia swamp forest along its eastern bank. This habitat is rare and threatened and this is an important intact remnant.

Key sensitive habitats, species and features:

• Swamp forest (dominated by Barringtonia and Ficus spp.).
• Sokhulu subsistence fishers depend on the river and estuarine fish.

1.4 Umfolozi River

The Umfolozi river has classic floodplain communities of reed-swamp and papyrus along its banks, but further upstream it is surrounded by sugar cane fields. The presence of the sugar-cane fields complicate the management of the river, since any blocking of the river may result in back-flooding of the fields. However, the river is currently flowing slowly and this mitigates potential impact of oiling as the river should tend to push pollutants out.

Shoreline (Cape St Lucia to Cape Vidal)

The Maputaland coast is characterised by a long straight sandy shoreline punctuated by log-spiral curve bays (zeta bays) caused by the entrapment of northward moving beach sediments by intertidal rock ledges (quaternary sandstone), and the erosion of the down-drift from the north side of these rock ledges. The area of concern is no exception, with zeta bays being present at Cape St Lucia and Crayfish Point. In addition, there are stretches of broad intertidal beachrock platforms at two places, which are exposed at spring low tide. These are derived from the semi-continuous aeolianite beachrock underlying the sandy beach. At three places along the shore between Cape St Lucia and Mapelane, these rocks form stable platforms for biological colonisation and support dense mussel beds and associated fauna. They are also productive rock lobster and reef fish habitats. The protection of these rock ledges is especially important in terms of biodiversity conservation targets, as the same types are not conserved elsewhere. There is a strip of sand above (to landward) of these platforms in the high intertidal zone and above the mean high water mark, which in turn is bordered by high vegetated sand dunes.

Key sensitive habitats, species and features:

• Biodiversity of rocky shore platforms: Crayfish Point, Railway Ledge, Zavini Ledge.
• Mussel beds (Perna perna).
• Sandy shores -- Ghost crabs, and white-fronted plovers nesting at high-water mark.
• Sokhulu community subsistence fishers depend on mussel beds 5km south of ship.

2. Offshore environment

The subtidal environment is characterised by a relatively narrow (2-7km) continental shelf with steep gradients, submarine canyons, submerged dune and beachrock systems and unconsolidated sediment. The fast flowing warm Agulhas current is the dominant oceanographic feature, but shelf oceanography is complex with current reversals. The GSLWP contains three main subtidal habitat types: reefs (both coral and rock), submarine canyons, and unconsolidated soft sediments. The mud deposits off the estuary mouths represent a specialised and rare habitat type, where the environmental conditions are similar to that of estuarine environments with murky turbid water, high concentrations of food and shelter from strong currents. These conditions are suitable for penaeid prawns and serve as nursery areas for juvenile fish. The marine offshore habitat adjacent to the St Lucia estuary is an important spawning area for grunter Pomadasys commersoni, stumpnose Rhabdosargus sarba and R. holubi and mullet Mugil and Liza spp.

The southern-most coral reef in the GSLWP (Leadsman Shoal) is north of Leven Point, some 30km north of Cape St Lucia, and are not in immediate danger of oil pollution. However, they are sensitive and vulnerable should the oil slick be blown northwards.

Humpback whales utilise the coastal waters off the GSLWP as a migratory corridor on both their northward and south migrations between tropical coastal breeding grounds and Antarctic feeding grounds. The southward migration is currently at its highest (September and October), with a offshore distribution centred at 3-5 kilometres. Southward migration speeds are approximately 5 km per hour. Whales (adults at least) are not feeding on the migration. The southward migration includes mother-calf pairs.

Other important species utilising the inshore waters include whale sharks and turtles. Turtles (loggerhead and leatherback) start nesting in October and are thus unlikely to be impacted at present, although they are currently offshore in the waters.

Coastal and offshore diving birds (e.g. gannets) are present offshore and are vulnerable to oiling.

Key sensitive species and features:

• Humpback whales on southward migration (mother-calf pairs) may be a concern.
• Offshore birds -- gannets, cormorants, etc.
• Coral reefs.
• Coelacanth.
• Muddy deposit area off St Lucia mouth (nursery for fish and prawns).

PREVENTATIVE MEASURES

This section documents the measures implemented (and the rationale for them) to prevent and minimize impact of the oil pollution.

Wetlands (Umfolozi/Umzunduze and St Lucia systems)

St Lucia estuary and lake

It is important to prevent oiled water from entering the St Lucia estuarine and lake system.

To this end the following precautionary measures have been taken:

• A 2km berm has been built across the beach to close off the St Lucia estuary mouth and prevent the sea from overtopping into estuary. This has been done using large bulldozers.
• The “back channel” that connects the Umfolozi and St Lucia estuaries has been closed to prevent water from the Umfolozi blind estuary area entering the St Lucia lake system.

Umfolozi -- Umzunduze estuary

The tidal currents around this estuary mouth are strong and it is therefore not practical to completely block water flow into the estuary. It is also probably not desirable to do so, given the potential for back-flooding in the Umfolozi River and flooding sugar cane fields. However, it is important to attempt to prevent entry of oil, and especially to protect the mangrove stand fringing this estuary and to limit water (and oil) flow into the “blind estuary” area.

The following precautionary measures have been taken:

• A floating boom has been positioned across the main channel into the mangrove forest.
• A sand bar to cordon off the blind lagoon north of the Umfolozi Mouth has been created using bulldozers. Note: it is necessary to ensure sea-water flushing of this system at least fortnightly to prevent stagnation.

Umzunduze River

This river is tidal for up to 15 km and is thus susceptible to oiling from seaward. It is important to protect the swamp forest. An additional consideration is the dependence of the Sokhulu subsistence fishermen on this river.

To prevent oil entering the river and reaching the swamp forest:

• A floating boom has been placed across the river mouth up-stream of the confluence with the Umfolozi river.

Umfolozi

The main Umfolozi river is exhibiting a slow seaward current flow and should not be totally blocked as this would result in a back-flood of the sugar canes upstream. It any case should have the capacity to push oily water out in the event of pollution. The main tidal movement in the Umfolozi-Umsunduze system is up the Umsunduze, and seawater seldom penetrates the Umfolozi upstream of the confluence. Thus the Umfolozi river itself should be fairly immune to an oil pollution event.

As a precautionary measure:

• A floating boom has been positioned temporarily across the Umfolozi mouth to absorb pollution.

MONITORING AND MITIGATION

The following monitoring is underway, and mitigation plans are to be implemented:

Monitoring

• Pollution monitoring -- shoreline, offshore and estuaries.
• Monitoring of bird populations in estuary mouth (daily) -- check for fouling.
• Monitor hump-back whales -- watch for animals in distress.

Management interventions

• Decontamination of oiled wildlife:
  • Bird rehabilitation and cleaning station established at St Lucia.
  • Crocodiles to be transferred to crocodile centre at St Lucia.
• Maintenance of estuary dynamics in closed mouths, by implementing breaching procedure to allow seawater flushing.
• Use of dispersant on oil offshore.
• Use of absorbent material to mop up oil in intertidal.
• Mechanical dispersal of oil -- Kuswag 1.
• If high probability of oiling in the Umfolozi mouth area (sandflats) -- employ “scaring” methods for birds.
• Translocation of crocodiles if oil pollution imminent.

CLEAN-UP AND REHABILITATION

Once the threat of oil pollution is over, detailed plans for the following clean-up and rehabilitation operations will be implemented:

• Clean up of oil deposits.
• Removal of sand berms in Umfolozi and St Lucia estuary mouths.
• Foredune rehabilitation where applicable.
• Remove oil aggregated absorbant from shoreline.
• Rehabilitation of roads and access ramps damaged during process.
• Release of rescued wildlife (crocodiles and birds).
• Ongoing monitoring programme to track recovery.