Our analyses of the incidence of cooperative breeding among South African birds differ from previous studies performed elsewhere in two respects. First, we distinguish between "obligate" (i.e. regular) and "facultative" (i.e. opportunistic) cooperative breeding species (OCS and FCS). Second, we have restricted our analyses to 217 South African bird species considered to be sufficiently well-studied in terms of their basic biology and life-history characteristics. This was done in order to control for the well-known bias against the often poorly-studied avifaunas of extreme environments such as rainforests and deserts. The results of our analysis do not accord fully with those of Australian birds by Ford et al. (1988). Cooperative breeding in South Africa is associated with seasonal environments, whereas in Australia the opposite is the case. Analyses of ecological factors that promote cooperative breeding among South African birds suggest that the evolutionary pathway to obligate and facultative breeding may be fundamentally different. First, OCS live mainly in savanna habitats that have predictable seasonal peaks in food availability, yet where the baseline level of food availability during the nonbreeding season is sufficient to support permanent residence by groups. Small to medium-sized birds of the African savannas are particularly vulnerable to avian predators, and foraging and roosting in permanent groups may enhance their survival. We propose that the benefits of obligate cooperative breeding are derived chiefly from survival of individuals away from the nest (i.e. during the nonbreeding season). Secondly, FCS live largely in unpredictable, seasonal steppe habitats. Under these conditions it may be impossible for birds to maintain permanent group territories, and variation in the tendency to breed cooperatively may depend largely on the opportunistic assessment of environmental conditions. We therefore suggest that birds (i.e. FCS) will opt to breed cooperatively only when conditions are unfavourable for independent breeding, and that the benefits thus accrued are chiefly related to reproduction.

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The consumption of Antarctic krill (Euphausia superba) by an “average-sized” (male 6994 kg; female 8249 kg), sexually mature Minke whale (Balaenoptera acutorostrata) was estimated, from stomach capacity, ingestion rate and respiratory allometry methods. Estimates obtained from the stomach capacity and respiratory allometry methods differed by 17%–23%. An “average-sized” male Minke whale consumes 37.2 t of krill during a 90-day stay, and an “average-sized” female Minke whale consumes 56.2 t of krill during a 120-day stay, in Antarctic waters during the austral summer. It is estimated that the Minke whale population in the Antarctic (60°S and higher) consumes 35.5 × 106 t of krill annually.

Subterranean herpetofauna comprise an estimated 20% of the world's amphibians and reptiles but are one of the least studied groups of terrestrial vertebrates. Monitoring population trends and threats to these species is dependent in part on quantitative historical data, which are generally lacking. One exception is a 1970 study conducted in Ndumu Game Reserve, South Africa. We revisited this area in 2004 and carried out comparative quantitative sampling in deciduous broad-leaf woodland and sand forest habitats. Our results show a 79% reduction in density of subterranean herpetofauna, as well as a reduction in diversity. Mann-Whitney tests show that the amphisbaenian Zygaspis vandami has undergone a significant reduction in density in both habitats sampled. We relate reductions in subterranean herpetofaunal densities to an increased density of the Reserve's ungulate grazers, suggesting a link between reduction in leaf-litter and soil macrofauna prey of the fossorial reptiles. This study highlights the need for quantitative surveys of subterranean herpetofauna to support future conservation efforts.

Invertebrates constitute a substantial proportion of terrestrial and freshwater biodiversity and are critical to ecosystem function. However, their inclusion in biodiversity monitoring and conservation planning and management has lagged behind better-known, more widely appreciated taxa. Significant progress in invertebrate surveys, systematics and bioindication, both globally and locally, means that their use in biodiversity monitoring and conservation is becoming increasingly feasible. Here we outline challenges and solutions to the integration of invertebrates into biodiversity management objectives and monitoring in protected areas in South Africa. We show that such integration is relevant and possible, and assess the relative suitability of seven key taxa in this context. Finally, we outline a series of recommendations for mainstreaming invertebrates in conservation planning, surveys and monitoring in and around protected areas.<p><strong>Conservation implications:</strong> Invertebrates constitute a substantial and functionally significant component of terrestrial biodiversity and are valuable indicators of environmental condition. Although consideration of invertebrates has historically been neglected in conservation planning and management, substantial progress with surveys, systematics and bioindication means that it is now both feasible and advisable to incorporate them into protected area monitoring activities.</p><p><strong>How to cite this article:</strong> McGeoch, M.A., Sithole, H., Samways, M.J., Simaika, J.P., Pryke, J.S., Picker, M., <em>et al</em>., 2011, ‘Conservation and monitoring of invertebrates in terrestrial protected areas’, <em>Koedoe</em> 53(2), Art. #1000, 13 pages. doi:10.4102/koedoe.v53i2.1000</p>