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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 (

Habitat change, mainly through the actions of humans, poses a threat to great white (Pelecanus onocrotalus) and pink-backed (P. rufescens) pelicans in northeastern KwaZulu-Natal, the southernmost distributions of these species on Africa’s eastern seaboard. This study assessed the relative importance and state of the potential pelican habitat in the northeastern KwaZulu-Natal region, focusing particularly on Lake St Lucia and the Phongolo River floodplain. Great white pelicans breed on islands in Lake St Lucia. Should these islands be lost through falling water levels or their becoming joined to mainland by deposits of silt, or by flooding, no suitable habitat for their breeding will remain in the region. By contrast, the pink-backed pelican nests in trees, and there appears to be plentiful alternative habitat. Lake St Lucia and, to a lesser extent, the Phongolo River floodplain, are important foraging areas for both pelican species. The hydrology of both these systems has been affected by human activities.Key words: breeding site, foraging, habitat assessment, Lake St Lucia, Pelecanus spp., pelicans, Phongolo River floodplain.

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.

Maputaland–Pondoland–Albany, South Africa has been identified as a biodiversity hotspot and centre for endemism. Odonata make good indicators of freshwater ecosystem health. Consequently we compiled a list of Odonata species recorded to date in the iSimangaliso Wetland Park. We then detailed important species in terms of endemism, conservation status, and potential as indicator species. Finally, we compared Odonata assemblages of different sites sampled within the park to illustrate habitat importance. Species identified during two formal surveys and incidental observations made during the study period were combined with an existing database to compile an accurate and up to date species list for the iSimangaliso Wetland Park. Data from this study were then analyzed to determine which water bodies had the most similar species composition. The Dragonfly Biotic Index (DBI) value of each study area was also determined. We recorded 68 odonate species in the iSimangaliso Wetland Park, adding 13 species to the Ezemvelo KwaZulu-Natal Wildlife database for the area. This brings the total number of Odonata species for the iSimangaliso Wetland Park to 86. Eight species are red-listed, 12 are restricted in South Africa to the coastal plains of northern KwaZulu-Natal, and the remainder occurs widely across the southern African savanna. Analyses indicate that species odonate assemblages were most similar in water bodies with comparable habitats. iSimangaliso Wetland Park is identified as an important area for Odonata diversity and endemism, a trend also reflected by the DBI values. Shifts in the existing species assemblages would indicate changes within the ecosystem and thus this species account provides necessary baseline data for the area. Species Conservation efforts should thus target water bodies of varying habitat types to protect greater species diversity.

The complex methodology used in many large-scale quantitative proteomics experiments often dictates an experimental design with small sample size and limited repetition. Variation in a complex dataset may hopefully arise from changes caused by the experimental perturbation, but could also arise due to technical noise (poor sample prep, run-to-run variation) and biological noise (normal differences between samples, especially present in clinical samples). Here, we apply principle component analysis (PCA) and unsupervised hierarchical clustering (HC) to the data generated from multi-variable difference gel electrophoresis (DIGE) experiments. This global perspective on multivariable datasets assesses whether the variation in the system describes the biological signal, rather than being derived from technical/biological noise whereby “significant” changes may arise stochastically. Although we use DIGE datasets as examples (due to the low technical noise), these issues are germane to all proteomics experimental platforms.

Whole animal studies suggest that tumor necrosis factor-alpha (TNF alpha) plays a central role in the endotoxin response. In vitro studies show that TNF alpha and endotoxin induce a similar range of metabolic changes to endothelial cells. However both endotoxin- and TNF alpha-induced cytotoxicity is not a feature of all endothelial cells lines. In recent studies, the authors have shown that endotoxin causes different responses in endothelial cells taken from two levels of the lung's circulation--main pulmonary artery and lung microvasculature. Endotoxin exposure caused cell death for cells cultured from the large pulmonary artery but not for those taken from lung periphery. The present study examined the effect of TNF alpha on endothelial cells cultured from two levels of the lungs' circulation--the main pulmonary artery and the lung microvasculature. End points examined included lactate dehydrogenase (LDH), prostacyclin, and prostaglandin E2 (PGE2) release and phase contrast microscopy. Exposure to TNF alpha resulted in a dose-dependent increase in LDH release and number of detached cells for cells of the pulmonary artery, whereas cells from the microvasculature seemed unaffected. At both levels, however, TNF alpha caused increased release of both prostacyclin and PGE2. The authors conclude that TNF alpha causes different effects in endothelial cells cultured from two levels of the same organ.

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

The early changes in pulmonary artery structure and the timing and development of right ventricular hypertrophy were examined in rats after ingestion of Crotalaria spectabilis; the arteries were distended with a Micropaque--gelatin mixture. The earliest change, detected at Day 3, is the appearance of new muscle in normally nonmuscular arteries. Increased medial wall thickness of the normally muscular arteries is apparent from Day 7, reaching significance in the smaller arteries from Day 10 and in the larger arteries from Day 14. A reduction in number of small, filled peripheral arteries is apparent at Day 14 and is significant at Day 21 as is the increase in the ratio of alveoli to arteries per unit area of section. Right ventricular hypertrophy is detected and significant at Day 21 and, like all the arterial changes, continues to increase to Day 35. Hypoxia produces similar changes to those described above, although without the inflammation seen after Crotalaria ingestion, but the time table is different. New muscle appears in both models at the same time, but the other changes appear more slowly after ingestion of Crotalaria spectabilis.

A single infusion of Perilla ketone (PK) into sheep causes marked increases in lung fluid and solute exchange in the absence of any alteration in either pulmonary arterial or left atrial pressures. These alterations are most compatible with increased pulmonary microvascular permeability. The present paper describes the morphologic changes that accompany the previously described alterations in lung function. In five anesthetized open-chest sheep, lung biopsy tissue was taken at baseline and at 15, 30, 60, 120, and 180 minutes after the start of a single infusion of PK (15-20 mg/kg given over a 20 minute period). Biopsy tissue was taken from different lobes of the lung in random sequence, fixed, and processed for light and electron microscopic examination. Three control sheep received the vehicle, dimethyl sulfoxide, alone. Just 15 minutes after the start of PK infusion, alveolar capillary congestion, accumulation of peripheral lung neutrophils, and intraalveolar and interstitial edema were apparent. Electron microscopy revealed early evidence of damage to both the microvascular endothelial cells and Type I pneumonocytes. The damage became more severe with time. From 30 minutes, occasional nonciliated cells in the airway epithelium exhibited dilated rough and agranular endoplasmic reticulum. Thus, PK causes rapid onset of pulmonary edema accompanied by structural evidence of damage to the microvascular endothelium and Type I pneumonocytes. Pulmonary inflammation was also evident. These structural changes occur before the described alterations in either pulmonary microvascular permeability or reduction in pulmonary compliance.