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Standing dead trees (or snags) are an important component of forest ecosystems, especially for tree cavity-nesting vertebrate species, but their prevalence in South African forests remains under studied. Consequently, we investigated forest structure, and the presence and abundance of snags in six southern mistbelt forests in the Eastern Cape, South Africa. These forests have had varying levels of timber extraction over the past 150 years or more. We found snags were relatively rare in all six forests (

White-breasted cormorants Phalacrocorax [carbo] lucidus breed around South Africa’s coast and at inland localities. Along the coasts of the Northern, Western and Eastern Cape provinces, numbers breeding were similar during the periods 1977–1981 (1 116 pairs at 41 localities) and 2008–2012 (1 280 pairs at 41 localities). Along the coast of KwaZulu-Natal (not counted in 1977–1981), 197 pairs bred at nine localities in 2008–2012, when the overall number breeding around South Africa’s coastline was about 1 477 pairs. Between the two study periods, numbers decreased in the Northern and Western Cape provinces following the loss of several breeding localities, but they increased in the Eastern Cape. In the Western Cape, however, numbers were stable east of Cape Agulhas and at nine well-monitored West Coast localities that were surveyed from 1978 to 2012. White-breasted cormorants breed throughout the year, with breeding at some localities more seasonal than at others and the timing of peaks in breeding varying at and between localities. In the vicinity of Saldanha Bay/Langebaan Lagoon (Western Cape), in Algoa Bay (Eastern Cape) and in northern KwaZulu-Natal, it is likely that birds moved between breeding localities in different years, although breeding often occurred at the same locality over several years. Human disturbance, presence of predators, competition for breeding space and occurrence of breeding by other waterbirds may influence movements between colonies. Securing sufficient good habitat at which white-breasted cormorants may breed will be important for conservation of the species. The species may breed at an age of 4 years, possibly younger. The bulk of their diet around South Africa’s coast consists of inshore marine and estuarine fish species that are not intensively exploited by humans.African Journal of Marine Science 2013, 35(4): 473–490

Little has been documented on large (>250 g), water-associated birds in the north-eastern KwaZulu-Natal, South Africa, that nest colonially and rely on suitable sites for breeding. The purpose of this study was to highlight these species and the importance of nesting sites for their effective conservation management. From 1920–2010, there were 622 records of 27 of these species breeding at more than 48 sites. Five sites accounted for 65% of these breeding events, four at Lake St Lucia, highlighting its importance for bird conservation. Several sites were abandoned. However, two new sites have established more recently (Nsumo Pan, Mkhuze Game Reserve; Nyamithi Pan, Ndumo Game Reserve) that are important in terms of number of individuals as well as variety of species. Some species (Pink-backed Pelican Pelecanus rufescens, Grey-headed Gull Larus cirrocephalus, Caspian Tern Sterna caspia, Great-white Pelican P. onocrotalus and African Spoonbill Platalea alba) have bred regularly but have used only a...

KwaZulu-Natal (KZN), South Africa, is the most southerly area in Africa in which the Pink-backed Pelican Pelecanus rufescens breeds. This area also boasts the most southerly breeding colony on the eastern seaboard of Africa for the Great White Pelican P. onocrotalus. Considerable amounts of data relating to the distribution and numbers of these two species in north-eastern KZN have been collected in a variety of ways by a number of people. These data were collated to estimate the distribution and status of the two pelican species and to evaluate any trends. There is no evidence of contraction or expansion in the distribution of either species. Numbers in south-eastern Africa are estimated to be 6 000–9 000 for the Great White Pelican and 600–900 for the Pink-backed Pelican. Numbers of both species were highly variable at the main locality, Lake St Lucia. For their long-term conservation it is necessary to take into account that neither population is restricted to the study area and that there are fluctuations in their distributions and numbers.OSTRICH 2010, 81(3): 179–188

In January 2004, Lake St Lucia, a major part of the Greater St Lucia Wetland Park, was reduced to a fraction of its normal capacity as a result of a severe drought in this region of KwaZulu-Natal, South Africa. After rains in the area, the lake level rose and then fluctuated considerably over the next 42 months. During the first 38 months the mouth of the estuary into the sea was closed. The area entered a second severe period of prolonged drought from mid 2005 through to the spring of 2006. Great white pelican (Pelecanus onocrotalus Linnaeus, 1758) numbers and lake levels were monitored during these 42 months. Pelican numbers were highly variable ranging from 0 to 6000. When lake levels were very low or too high, no pelicans were present. Pelican numbers appeared more indicative of food availability. Implications of these trends to the management of the lake and the conservation of the avifauna are discussed. It is suggested that the great white pelican could be used as an indicator species for the fish dynamics of the lake at medium to low lake levels. Resume En janvier 2004, le lac Ste Lucia qui est une partie majeure du Greater St Lucia Wetland Park fut reduit a une fraction de sa capacite normale suite a une grave secheresse dans la region du KwaZulu-Natal, en Afrique du Sud. Apres des pluies dans la region, le niveau du lac est remonte et a considerablement fluctue au cours des 42 mois qui ont suivi; pendant les 38 premiers de ces mois, la bouche de l’estuaire vers la mer est restee fermee. La region a connu une nouvelle periode de secheresse prolongee entre le milieu de 2005 et le printemps 2006. Le nombre de grands pelicans blancs (Pelecanus onocrotalus Linnaeus, 1758) et le niveau du lac furent suivis pendant ces 42 mois. Le nombre de pelicans etait tres variable et il a fluctue entre 0 et 6000. Lorsque le niveau du lac etait trop bas ou trop haut, il n’y avait aucun pelican. Le nombre de pelicans semble indiquer davantage la disponibilite de la nourriture. L’on discute des implications de ces tendances pour la gestion du lac et la conservation de l’avifaune. On suggere d’utiliser le grand pelican comme indicateur pour la dynamique des poissons du lac lorsque le niveau de ce dernier est moyen a bas.

The Great White Pelican Pelecanus onocrotalus and the Pink-backed Pelican P. rufescens are flagship species for the Greater St Lucia Wetland Park, north-eastern KwaZulu-Natal, South Africa. The traditional breeding sites for the Great White Pelican and the Pink-backed Pelican are confined to Lake St Lucia and Nsumo Pan, respectively. Considerable amounts of data have been collected since 1933 relating to the breeding efforts of these populations, and these data have been collected in a variety of ways. This study represents an attempt to collate and summarise these data and to make some estimations of the breeding success of the two pelican species in south-eastern Africa. Breeding attempts of Great White Pelican have been erratic and have had varied success. Although less erratic, only small numbers of the Pink-backed Pelican have bred.

Briza Publications, Pretoria, South Africa 192 pages, colour photos, icons and indexing, laminated soft cover ISBN 978-1-875093-89-2, recommended price R95 Ostrich 2008, 79(1): 113

At present, six groups of chronic pulmonary hypertension (PH) are described. Among these, group 1 (and 1′) comprises a group of diverse diseases termed pulmonary arterial hypertension (PAH) that have several pathophysiological, histological, and prognostic features in common. PAH is a particularly severe and progressive form of PH that frequently leads to right heart failure and premature death. The diagnosis of PAH must include a series of defined clinical parameters, which extend beyond mere elevations in pulmonary arterial pressures and include precapillary PH, pulmonary hypertensive arteriopathy (usually with plexiform lesions), slow clinical onset (months or years), and a chronic time course (years) characterized by progressive deterioration. What appears to distinguish PAH from other forms of PH is the severity of the arteriopathy observed, the defining characteristic of which is “plexogenic arteriopathy.” The pathogenesis of this arteriopathy remains unclear despite intense investigation in a variety of animal model systems. The most commonly used animal models (“classic” models) are rodents exposed to either hypoxia or monocrotaline. Newer models, which involve modification of classic approaches, have been developed that exhibit more severe PH and vascular lesions, which include neointimal proliferation and occlusion of small vessels. In addition, genetically manipulated mice have been generated that have provided insight into the role of specific molecules in the pulmonary hypertensive process. Unfortunately, at present, there is no perfect preclinical model that completely recapitulates human PAH. All models, however, have provided and will continue to provide invaluable insight into the numerous pathways that contribute to the development and maintenance of PH. Use of both classic and newly developed animal models will allow continued rigorous testing of new hypotheses regarding pathogenesis and treatment. This review highlights progress that has been made in animal modeling of this important human condition.