Boulders Beach is situated in Simon’s Town on the False Bay coast of the Cape Peninsula, 35 km south of Cape Town. The site consists of small beaches with granite boulders. The vegetation at Boulders consists mainly of thickets of coastal strandveld that cover approximately 3 ha. The IBA boundaries coincide with the Boulders Beach portion of the Table Mountain National Park and include the section of land to the south known as Burghers’ Walk.
African Penguin Spheniscus demersus colonised Boulders Beach in 1985 when two breeding pairs were recorded. The colony has increased steadily: there were approximately 700 active nests in 1997 and in 2014 more than 800 breeding pairs were present, representing approximately 6% of the global population. This is one of only three mainland breeding sites in the world. The penguins use the vegetation for shelter while breeding and moulting. Small numbers of Crowned Cormorant Phalacrocorax coronatus occasionally roost on the rocks. Cape Cormorant P. capensis, however, can now be seen roosting in very large numbers and has been included as an IBA trigger species. African Black Oystercatcher Haematopus moquini often occurs on the beach and an estimated two breeding pairs use the site regularly. Cape Spurfowl Pternistis capensis and Cape Bulbul Pycnonotus capensis are strandveld residents. Cape Sugarbird Promerops cafer occasionally visits from the slopes above the beach.
Globally threatened species are African Penguin (3 078 individuals and 962 breeding pairs; this and the following figures from regular SANParks census counts, 2014), African Black Oystercatcher (two breeding pairs) and Cape Cormorant (10 000 individuals).
The largest mammal found along this section of coast is the Cape clawless otter Aonyx capensis. Other mammals frequently seen include the Cape grey mongoose Galerella pulverulenta, water mongoose Atilax paludinosus, large-spotted genet Genetta tigrina and rock hyrax Procavia capensis. The most common mammal is the rock hyrax, which prefers the granite rocky outcrops surrounded by dense vegetation. Reptiles seen along this coastline include southern rock agama Agama atra, red-sided skink Trachylepis homalocephala, Cape skink T. capensis, short-legged seps Tetradactylus seps, Knox's desert lizard Meroles knoxii, marbled leaf-toed gecko Afrogecko porphyreus, Cape cobra Naja nivea, puff adder Bitis arietans and boomslang Dispholidus typus.
The threats to Boulders Beach are synonymous with the threats to the African Penguin across its range as this is the primary trigger species for this IBA. Competition with commercial fisheries, especially purse-seining for surface-shoaling fish such as pilchard Sardinops sagax, has been implicated as one of the most significant factors causing the global population decline of African Penguin.
Another problem is chronic pollution. Difficult to predict or control, it occurs when tankers break open, wash their tanks, dump cargo or pump bilge and crude oil or other environmental pollutants into the sea. Penguins are affected particularly badly by such spills and a single oil disaster can severely affect populations. The Apollo Sea oil-spill disaster in June 1994 resulted in many penguin deaths in and around the Cape Peninsula.
Land-based threats at Boulders include predation by feral cats Felis catus and small-spotted genet Genetta genetta. Disturbance due to uncontrolled tourism and recreational use in areas adjacent to Table Mountain National Park is a problem. As a result of strict management measures at Boulders, the penguins at this site are remarkably accustomed to people and the colony continues to increase in numbers and size, despite its exposure to large numbers of visitors. Road-kills, due to the colony’s proximity to a major road, do occur but these have reduced in number since the appointment of dedicated penguin monitors. Speeding vehicles, however, remain an ongoing threat to the safety of penguins on the road.
A portion of this IBA is a declared national park and therefore receives full legislative protection under the management of SANParks. In line with this declaration, a comprehensive management plan exists, which guides the implementation of the necessary conservation actions required at the site. However, the Burghers’ Walk section of the IBA, which is managed by the City of Cape Town, does not enjoy the same protection or conservation status.
Conservation actions at Boulders include the control of tourism activities; raising visitors’ and local residents’ awareness about the penguins; dedicated monitors patrolling adjacent areas to reduce disturbance; the monitoring of stressed birds and the appropriate response protocol when necessary; and a chick-bolstering project to raise additional birds to further supplement the population.
A Threatened Species Management Plan, involving all stakeholders, has also been produced specifically for the African Penguin to guide conservation efforts for this species across its range.
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