Browsing by Author "Baltazary, Angelamercy"

Now showing 1 - 2 of 2

Vigilance Behaviour of Wild Herbivores when Foraging With or Without Livestock
(Canadian Center of Science and Education, 2019-02-28) Baltazary, Angelamercy; Roskaft, Eivin; Treydte, Anna C.
In African savannas, and many other rangelands around the world, wildlife presently find themselves interacting with livestock. Many studies have been conducted on vigilance behaviour in response to presence of predators on foraging grounds, but few scientists have included the presence of livestock and how this affects vigilance when foraging together with wild herbivores. As Ngorongoro Conservation Area (NCA) is an important example of wildlife grazing together with livestock, this phenomenon must be understood to achieve a sustainable land use management plan, particularly in Ngorongoro Conservation Area and in other protected areas. Behavioral observations of wildlife and livestock species were conducted from a vehicle driving along transects within NCA. Once a group was sighted the vehicle was stopped and sighting information recorded. Four species of wild herbivores including plains zebra (Equus burchelli), Thomson’s gazelle (Gazella thomsonii), Grant’s gazelle (Gazella granti) and Wildebeest (Connochaetes taurinus) were studied together with the following livestock species including cattle (Bos taurus), goats (Capra aegagrus hircus) and sheep (Ovis aries), in different seasons. 158 groups were recorded. In dry season 47 non –mixed groups (without livestock) and 30 mixed groups (with livestock) were recorded, while, during wet season 49 non -mixed groups and 32 mixed groups were recorded. Behavior was classified as feeding, grooming, laying down, ruminating, grooming, moving, and looking with head up (vigilance) with the use of the focal animal sampling method. Wildlife decreased their foraging time while they increased vigilance behavior when livestock were present; however, more studies are still for a wider conclusion
Wild herbivore vigilance and grass regrowth under livestock grazing in Ngorongoro, Tanzania
(NM-AIST, 2019-04) Baltazary, Angelamercy
Pastoralists consider wildlife the biggest competitors over resources for livestock while little is known about the potentially positive or negative behavioural effects that livestock can have on wildlife when foraging together. In the Ngorongoro Conservation Area (NCA), wildlife has been grazing together with livestock for centuries but knowledge on how this impacts wildlife feeding behaviour or grazing intensity on grass regrowth is scarce. Behavioural observations of wildlife and livestock species were conducted from a vehicle driving along transects within NCA. Four groups of wild herbivore species including plains Zebra (Equus burchelli), Thomson’s gazelle (Gazella thomsonii), Grant’s gazelle (Gazella granti) and Wildebeest (Connochaetes taurinus) were observed, grazing either with or without livestock species, i.e., cattle (Bos taurus), goats (Capra aegagrus hircus) and sheep (Ovis aries), over two different seasons. Out of 158 groups in total, on average 48 herds without and 31 herds mixed with livestock were recorded. Moving cages were used to assess the effect of different wildlife and livestock grazing pressure on grass regrowth (height and coverage). Results show that wildlife decreased their foraging time while they increased vigilance behaviour when grazing together with livestock, particularly when herders were present, compared to grazing without livestock. The grass regrowth potential decreased with increasing grazing intensity. Therefore, in contrast to foraging facilitation theory we conclude that the presence of livestock does not seem to be beneficial for wild herbivores and that wildlife protection area, in which pastoralists cannot lead their cattle, are important for a sustainable management of the NCA.