Territoriality of Cape Sugarbirds (Promerops cafer) between and within breeding seasons

Cape Sugarbirds are southern African endemics, found in fynbos vegetation of the Western and Eastern Cape Provinces of South Africa, and they feed almost exclusively on the nectar of Protea inflorescences. Breeding male Sugarbirds are highly territorial and defend resources for themselves, their mates and their offspring. Sugarbirds, however, often leave their breeding territories in search of food during the dry season and return to the same breeding sites each year, thus experiencing an annual cycle of movement from one food source to another. Male territory size as well as breeding success, were determined over two breeding seasons for a population in the Helderberg Nature Reserve in the Western Cape Province. Sugarbird fledgling success was significantly greater for males defending large territories. Males moved or increased the size of their territories between seasons, possibly to improve breeding success, but no changes in territory size were observed during the breeding season.Articl

Territoriality and breeding success in Gurney's sugarbird, Promerops gurneyi

Territory size and quality were determined for Gurney's sugarbirds in Qwaqwa National Park, northeastern Free State, South Africa. Changes in territory size of Gurney's sugarbirds during the six-month season reflect increases in numbers of territorial birds and inflorescences at mid breeding season, and declines in both at the end of the breeding season. Only 25 % of pairs laid eggs, and mating appears to have been constrained by low nectar and arthropod energy availability, and the costs associated with the defence of large territories. Reproductive success was directly related to arthropod availability on territories, with pairs not even appearing to attempt breeding if this is low. Males with longer tails and wider sixth primary feather bulges defended larger territories, indicating that ornament size and displays of Gurney's sugarbirds may be important in territory maintenance.Articl

Foraging and territorial behaviour of male Cape and Gurney's sugarbirds (Promerops cafer and P. gurneyi)

Foraging and territorial behaviour of Cape and Gurney's sugarbirds were studied in the Western Cape and eastern Free State of South Africa, respectively. Cape sugarbirds spent most of their time in territory defence and resting at all times of the day - both at mid breeding season and at the end of the breeding season - and only about ten percent of their time foraging. Cape sugarbirds may feed in the morning to replenish energy deficits and water imbalances experienced at night, and then maintain a high feeding rate at midday to maximize energy gain when nectar energy availability is greatest. Gurney's sugarbirds, by contrast, showed little variation in the amount of time spent feeding on nectar throughout the day. More dispersed or lower availability of food may have constrained vocal activity in Gurney's sugarbirds, which spent most of their time throughout the day perching silently on the tops of trees. In Cape sugarbirds, feeding preferences for particular Protea species changed in relation to their flowering seasons, and reduced inflorescence availability during the breeding season is related to increased perching and decreased territory defence at midday.Articl

Territoriality and breeding success in Gurney’s sugarbird, Promerops gurneyi

Territory size and quality were determined for Gurney’s sugarbirds in Qwaqwa  National Park, northeastern Free State, South Africa. Changes in territory size of Gurney’s sugarbirds during the six-month season reflect increases in numbers of territorial birds and inflorescences at mid breeding season, and declines in both at the end of the breeding season. Only 25 %of pairs laid eggs, and mating appears to have been constrained by low nectar and arthropod energy availability, and the costs associated with the defence of large territories. Reproductive success was directly related to arthropod availability on territories, with pairs not even appearing to attempt breeding if this is low. Males with longer tails and wider sixth primary feather bulges defended larger territories, indicating that ornament size and displays of Gurney’s sugarbirds may be important in territory maintenance.Key words: food availability, ornament size, territory maintenance

Plasma Endotoxin Levels Are Not Increased in Schistosoma mansoni-Infected Women without Signs or Symptoms of Hepatosplenic Disease

Elevated circulating endotoxin levels in the plasma of patients with advanced hepatosplenic schistosomiasis caused by Schistosoma mansoni have been reported, possibly caused by parasite egg-induced intestinal mucosal breaches facilitating bacterial access to the bloodstream. Neither endotoxin levels in people with S. mansoni but without hepatosplenic disease nor the impact of treatment on endotoxin levels have been described. We used a methodically optimized Limulus amebocyte lysate assay to measure plasma endotoxin in community-dwelling women from an S. mansoni-endemic area without clinical hepatosplenic disease. We found no difference in baseline mean plasma endotoxin levels between those with (n = 22) and without (n = 31) infection (1.001 versus 0.949 EU/mL, P= 0.61). Endotoxin levels did not change in schistosome-infected women after successful treatment (1.001 versus 1.093 EU/mL, P = 0.45) and were not correlated with circulating anodic antigen or stool egg burden. Our findings do not support the hypothesis that translocating eggs in S. mansoni infection introduce bacterial sources of endotoxin to the circulation.Host-parasite interactio

Gene Expression Differences in Host Response to Schistosoma haematobium Infection

Cancer Signaling networks and Molecular Therapeutic