Geographical and temporal variation in the diet of Bank Cormorants Phalacrocorax neglectus in South Africa

Seabirds of the Benguela Ecosystem: Utilisation, Long-Term Changes and Challenges

“…The shifts may have been influenced by localised overfishing [39,41] and environmental change [40,42]. At the same time, an increased contribution of bearded goby Sufflogobius bibarbatus to the diet of Bank Cormorants off western South Africa suggested a southward expansion of the Namibian stock of this fish species [43]. When Namibia's sardine stock collapsed in the 1960s, its range contracted to the north [44] and it was largely replaced by bearded goby, jellyfish and possibly Cape horse mackerel Trachurus capensis [45,46].…”

“…A second measure that could enhance food availability is the identification and implementation of thresholds (below which fishing would be disallowed) of forage fish abundance (or availability) that are necessary to maintain adequate reproduction and survival of dependent predators [71][72][73]. In addition to abundance and availability of food, quality of prey is an important consideration if energetic requirements of seabirds are to be met [43,74,75]. A third means to achieve sufficient food is to offset mismatches in the distributions of breeding localities and prey of seabirds through the establishment of colonies nearer to the food supply.…”

Waterbirds: Birds of a feather flock together

“…The articles in this special issue are grouped largely into those focused on waterbirds of inland aquatic environments (de Souza et al 2019;Gula et al 2019;D'Urban Jackson et al 2019;Lee et al 2019;Neb et al 2019) and those focused on waterbirds in coastal and marine environments (Brown et al 2019;Dyer et al 2019;Sherley et al 2019;Tree et al 2019;Vanstreels et al 2019). Among the studies concentrating on inland waterbirds is one of the first attempts to quantify the long-suspected hybridisation between invasive Mallard Duck Anas platyrhynchos and native Yellow-billed Duck A. undulata in South Africa (de Souza et al 2019).…”