Coastal Seabirds

The waters off the southern African coast are one of the most productive in the world, thanks to the cold upwelled waters of the Benguela Current bringing nutrients to the surface layers. In addition to the Southern Ocean specialists such as albatrosses and petrels that frequent our waters, South Africa has several species of seabirds that breed on the mainland or inshore islands. Many of these birds are under threat from human activities including fishing, oil spills and the expanding ocean economy and climate change.

The Coastal Seabirds programme aims to conserve some of these threatened and iconic seabirds. Our work includes species-focused projects such as those on the African Penguin (see below and here to read about our work to create new penguin colonies) as well as larger scale efforts to ensure fish stocks are managed to take seabirds into account and to protect important seabird habitats. BirdLife South Africa’s work on coastal seabirds is supported primarily by the Charl van der Merwe Trust and the Isdell Family Foundation.

Ecosystem Approach to Fisheries Management

Fisheries Management

The west coast marine ecosystem is strongly influenced by the availability of just three species of fish as sources of food – anchovy, sardine and red-eye (collectively referred to as forage fish). The entire ecosystem depends on there being sufficient forage fish that play a critical link between plankton and predators. Many species depend on these small fish, from the commercially important hake and yellowtail that eat the forage fish, to the sharks and tuna that eat those bigger fish, to seabirds, seals, dolphins, and whales. Forage fish are the main prey for three species of endemic seabirds, African Penguins, Cape Gannets and Cape Cormorants, all of which have been classified as Endangered by the IUCN.

Fishing quotas have historically been set without considering the distribution of fish and this has not changed with the shift in fish distribution from the west to the south coast. We are working with stakeholders and government to ensure that fishery management takes non-uniform fish distributions into account. We are also working with partners to develop a suite of thresholds for indicator species, which include other seabirds and fish species that could indicate poor ecosystem function and trigger management action.

Marine Protection: identifying and protecting important seabird habitat

Part of ensuring that seabirds have enough food is to create protected areas for them where fishing does not take place. Preliminary results show that creating a 20 km fishing exclusion zone around an African Penguin breeding colony can have positive effects on both adult ands chicks, since the penguins don’t have to swim as far to find food. Along with other partners, we are collecting data to demonstrate this effect and engaging with the Department of Forestry, Fisheries and the Environment to use this information to conserve penguins and other seabirds.

Filling the gaps: tracking seabirds outside of the breeding season

The distribution of breeding seabirds is constrained around their colonies as they must regularly return to their nests to incubate eggs and care for dependent young. Outside of the breeding season, these foraging constraints are relaxed, and seabirds expand their distribution and target distant profitable foraging habitats. The larger distribution of non-breeding seabirds increases the probability of the birds interacting with potentially risky anthropogenic activities.

The post-breeding and pre-moult periods are energetically demanding for seabirds as they undergo plumage replacement and restore energy reserves lost during the breeding season. Good foraging conditions (i.e. sufficient prey) is important during this period and poor foraging conditions can have carry-over effects into the breeding season (e.g. deferred breeding or lower breeding success).

This period is especially important for penguins as, unlike other seabirds, they replace their entire plumage in just a few weeks during which they are land bound and fasting. During their moult, penguins lose up to 50% of their body mass and if they do not commence their moult with sufficient fat reserves to complete the moult and return to sea, they starve.

Little is known about the non-breeding distribution of South Africa’s coastal seabirds. However, BirdLife South Africa has been tracking the African Penguin before and after they moult since 2012. These data are extremely valuable and have uncovered the massive migrations these species undergo during two critical life history stages as well as identified important areas in which they concentrate. The Coastal Seabird Programme within BirdLife South Africa is committed to continuing this research and expanding it to two other Endangered coastal seabird species: the Cape Cormorant and Cape Gannet. Very little is known about the non-breeding distribution of these two species. However, if BirdLife South Africa can identify common areas shared by the Cape Cormorant, Cape Gannet and African Penguin, three species largely dependent on anchovy and sardine, we can highlight areas that are important to the seabirds and in need of conservation.

Mitigating maritime threats

In an increasingly threatened marine environment under global change phenomena such as climate change and the expansion of the ocean economy it is imperative that we improve our ability to understand marine ecosystems at temporal scales that are conducive to effective marine ecosystem management. Seabirds are useful and practical indicators of ecosystem condition and have the potential to reflect habitat conditions in near-real time. The Coastal Seabird Team is working with scientists and engineers at Nelson Mandela University, the University of Paris, the University of Cape Town and the Southern African Foundation for the Conservation of Coastal Birds (SANCCOB) to establish a suite of technologies to monitor the impacts of marine noise pollution on African Penguins in Algoa Bay. An Automated Penguin Monitoring System (APMS, including a weighbridge, pit-tag reader, processor and cell-phone transmission system) has been installed on St Croix Island to gauge the response of penguins to human activities in the bay. We are particularly concerned about the exponential increase in shipping traffic in the bay in recent years and associated heightened levels of marine noise. The APMS will be used to assess the impacts of different noise levels on penguins and this information will be used to advocate for sustainable maritime management in Algoa Bay.