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Simple Summary: This study deals with the role of predator pressure on group formation in the Helmeted Guineafowl, a large sub-Saharan highly social galliform. We focused on a population from South Africa exposed to the frequent chase of both aerial and terrestrial predators, namely, eagles and jackals, recording prey and predator behaviour along with the outcome of predatory encounters. While all attacks were directed to prey aggregates rather than lone individuals, a tendency for chasing groups of a larger size seemingly emerged in jackals. However, unlike aerial predators, these do not seem to induce high fear in guineafowl, eliciting hardly predictable anti-predator responses. This arguably suggests that these galliforms perceive eagles and jackals differently despite the comparable hunting success. While the high predator-induced fear points to a well-established predator–prey system in the case of aerial predators, jackals, mostly carrion eaters, are perceived as a minor threat accounting for the failure in eliciting a well-defined defensive behaviour. Little is known about landbird group dynamics in response to predation. Here, we describe the interactions between the Helmeted Guineafowl (Numida meleagris) and its predators regarding the survival advantages grouping behaviour may provide. Livestream webcam observations were conducted in Madikwe Game Reserve (South Africa) from August 2020 to August 2021. Emphasis was placed on predator–prey interaction and its effect on group size and structure in a spatial framework. We hypothesise that while grouping is crucial for a number of daily activities in this highly social species, it might turn into a higher predatory pressure. We found, indeed, that the probability of attacks by black-backed jackals (Lupulella mesomelas) significantly increased with guineafowl group size, unlike what happened with raptors. Moreover, when attacked by jackals, the birds responded by standing close to each other. These results suggest, in line with the proposed hypothesis, that a trade-off occurs between the defensive function of grouping in this galliform and the probability of jackal attack that increases as a function of prey group size. Nevertheless, we argue that Helmeted Guineafowl cooperative social groups also play a role as a defensive strategy against predators, with the many-eyes and dilution effects likely compensating for the higher predatory pressure. [ABSTRACT FROM AUTHOR]

This study describes the relationship between Helmeted Guineafowl Numida meleagris and invasive alien trees on livestock and maize farms south-east of Johannesburg, Gauteng province, South Africa. The dependence of the birds on alien trees affects strategies for the removal of these trees. During June to December 2014, Helmeted Guineafowl were recorded weekly on maps along a 42 km transect. Since Helmeted Guineafowl live in cohesive social groups of 15-20 birds, they roost communally in one or two trees during winter rather than spreading across an entire tree grove. The distribution of alien trees across the landscape in patches has enabled Helmeted Guineafowl flocks to reach new feeding patches near to roosting trees, as old feeding patches are depleted. One Helmeted Guineafowl flock of 15-20 birds requires ∼0.09 ha covered with mature alien trees for roosting. Suggestions are presented relating to the reduction of alien trees in compliance with the Conservation of Agricultural Resources Act 43 of 1983 and conservation of Helmeted Guineafowl. [ABSTRACT FROM AUTHOR]

Background: Generally speaking, playbacks were often ineffective to determine the group sizes of birds since mainly males from leks responded. This limitation has not been tested properly for flocking birds such as Crested Guineafowl (Guttera edouardi) with the view to use it as a counting method. The aims of the study reported in this paper were (1) to describe the calls of Crested Guineafowl in a social context; (2) to interpret calls in an evolutionary context; and (3) to demonstrate that playbacks can be used to locate and count Crested Guineafowl in small isolated forests. Methods: The vocal behavior of Crested Guineafowl was observed during a survey conducted in the Umhlanga Lagoon Nature Reserve (KwaZulu-Natal, South Africa) from November 2010 to June 2012. Transect line observations and sound playback methods were used. Results: The behavioral context and structure of calls were described. The eight calls described for Crested Guineafowl were produced mainly to unite flock members in the dense understory, where visibility was poor, and to repel intruders. When not disturbed, Crested Guineafowl were quiet and only made soft contact calls. Conclusions: The high rate of call back and the fact that flocks invariably approach the source of the call en masse, shows that field researchers are able to assess the population size of Crested Guineafowl with sound playbacks along a transect. The value of playbacks as a conservation tool is assessed. [ABSTRACT FROM AUTHOR]

This article describes flocking behaviour and dispersion of Helmeted Guineafowl, Numida meleagris,on and aroundmaize fields during the crop-sowing period (November-December), reflects diet analyses and estimates seed loss. A field transect survey (80 km) was conducted throughmaize farms in the Heidelberg, Vaaldamarea (Gauteng province) and the Balfour area (Mpumalanga province) in South Africa during 2013 to countGuineafowl.Maize, Zeamays, seed loss ascribed to Guineafowl was estimated to be <0.12% of the total harvest. This lowimpact is probably due to the lowdensity ofGuineafowl because of breeding territories required by pairs. [ABSTRACT FROM AUTHOR]

The responses of ground-dwelling birds to heat and cold stress encompass a variety of behavioural, physiological and even morphological mechanisms. However, the role of glabrous skin in this respect has been marginally addressed so far. The Helmeted Guineafowl (Numida meleagris) is a landfowl distributed across Sub-Saharan Africa with eight traditionally recognised extant subspecies. Among the most prominent morphological traits underlying intraspecific variability are size and pigmentation of the bare throat skin (or sack), which might be related to the different habitats and environmental conditions across its wide range. In order to explore the Helmeted Guineafowl range-wide sack variation and pigmentation in relation to thermoregulation and sexual signalling, we collected morphometric and environmental information for N. m. coronata integrating field data with the inspection of photographic material encompassing seven subspecies and environmental information from their habitats. Field data evidenced that sack size was significantly correlated with ambient temperature, thus pointing to a likely involvement of the throat sack in thermoregulation. When the pictorial data from all subspecies were pooled, sack size correlated negatively with biomass, rainfall and humidity, while a positive correlation was found with annual solar irradiation. Sack size correlated positively with monthly temperature variation among the blue-throated subspecies from southern Africa as opposed to the black-throated subspecies ranging north to Zambia and Mozambique. Still, in this latter group the sack was often larger during winter months, possibly to maximise solar radiation absorbance. Noteworthy, sack size was related to sex dimorphism in two subspecies. Sack morphology and colour in the Helmeted Guineafowl likely modulate body temperature by evaporative cooling or heating upon needs, but in some subspecies it is also seemingly related to sexual signalling. Additional studies are needed to fully understand the multifunctionality of this important morphological feature in this species. [ABSTRACT FROM AUTHOR]