Vegetation, Wildlife, and Livestock Responses to Planned Grazing Management in an African Pastoral Landscape

Abstract

Rangelands are vital for wildlife conservation and socio‐economic well‐being, but many face widespread degradation because in part of poor grazing management practices. Planned grazing management, typically involving time‐controlled rotational livestock grazing, is widely touted as a tool for promoting sustainable rangelands. However, real‐world assessments of its efficacy have been lacking in communal pastoral landscapes globally, and especially in Africa. We performed landscape‐scale assessment of the effects of planned grazing on selected vegetation, wildlife, and cattle attributes across wide‐ranging communally managed pastoral rangelands in northern Kenya. We found that planned grazing enhanced vegetation condition through a 17% increase in normalized difference vegetation index, 45–234% increases in herbaceous vegetation foliar cover, species richness and diversity, and a 70% reduction in plant basal gap. In addition, planned grazing increased the presence (44%) and species richness (53%) of wild ungulates and improved cattle weight gain (>71%) during dry periods when cattle were in relatively poor condition. These changes occurred relatively rapidly (within 5 years) and despite grazing incursion incidents and higher livestock stocking rates in planned grazing areas. These results demonstrate, for the first time in Africa, the positive effects of planned grazing implementation in communal pastoral rangelands. These improvements can have broad implications for biodiversity conservation and pastoral livelihoods. Copyright © 2017 John Wiley & Sons, Ltd.

Forb ecology research in dry African savannas: Knowledge, gaps, and future perspectives

“… Superscripts refer to selected studies only. 1 Buitenwerf et al (), 2 O'Connor (), 3 Gilo and Kelkay (), 4 Jacobs and Naiman () , 5 Odadi et al (), 6 Young et al (), 7 Zerbo et al (), 8 Dreber and Esler (), 9 O'Connor, , 10 Shackleton (), 11 Walker and Knoop (), 12 Belsky et al (), 13 Augustine (); 14 Ludwig, De Kroon, Berendse, & Prins, (), 15 van der Waal et al (), 16 Linstädter et al (), 17 Muvengwi et al (), 18 Masunga et al () , 19 Smit (), 20 Dreber et al (), 21 Rutherford et al (), 22 Hejcmanová et al (), 23 Odadi et al (), 24 Tessema et al (), 25 Angassa and Oba (), 26 Keya (), 27 Metzger, Coughenour, Reich, and Boone (), 28 Hanke et al (), 29 Tessema et al (), 30 Wesuls et al (), 31 Riginos et al (), 32 Riginos and Grace (), 33 Koerner et al (), 34 Belsky et al (), 35 Linstädter et al (), 36 Britz and Ward (), 37 Burkepile et al (), 38 Eby et al (), 39 Mlambo et al (), 40 Chikorowondo et al (), 41 Clegg and O'Connor (), 42 Traill (). …”

“…Although such a herbaceous layer may still provide a nutritious graze or browse for large and small stock (Donaldson & Kelk, 1970; section 3.4), the potential favoring of single species can have lasting effects on overall carrying capacities and livestock production (Wagner et al, ). Livestock grazing regimes affect the composition and structure of herbaceous communities and forb assemblages in multiple ways depending on the intensity (Dreber et al, ; Hanke et al, ; Linstädter et al, ; Rutherford et al, ), duration (Odadi, Fargione, & Rubenstein, ; Tessema et al, ), and seasonality (Angassa & Oba, ; Keya, ) of grazing impacts. Similarly, the type of herbivory and grazer mix may select for certain forb species (Odadi et al, ; compare section 3.4).…”

“…Livestock grazing regimes affect the composition and structure of herbaceous communities and forb assemblages in multiple ways depending on the intensity (Dreber et al, ; Hanke et al, ; Linstädter et al, ; Rutherford et al, ), duration (Odadi, Fargione, & Rubenstein, ; Tessema et al, ), and seasonality (Angassa & Oba, ; Keya, ) of grazing impacts. Similarly, the type of herbivory and grazer mix may select for certain forb species (Odadi et al, ; compare section 3.4). In this connection, grazing‐relevant traits like forb perenniality were reported to either increase or decrease under severe grazing pressure by livestock (Hanke et al, ; Linstädter et al, ; Rutherford et al, ); that is, responses in forb functional types are not consistent across savannas.…”

“…For the answers, the local status of forb communities can contribute in many respects, especially to impact assessments and an improved understanding of system dynamics. (Odadi et al, 2017;compare section 3.4). In this connection, grazing-relevant traits like forb perenniality were reported to either increase or decrease under severe grazing pressure by livestock (Hanke et al, 2014;Linstädter et al, 2014;Rutherford et al, 2012); that is, responses in forb functional types are not consistent across savannas.…”

“…Grazing-induced structural changes often refer to changes in herbaceous biomass, where the contribution of forb species can vary with their palatability to the type of livestock (Keya, 1998) with consequences for overall herbaceous diversity (Angassa & Oba, 2010). Compared to grasses, however, the grazing responses of forbs in terms of abundance, cover, and/or richness may be much weaker (Britz & Ward, 2007;Linstädter et al, 2014;Odadi et al, 2017;Rutherford & Powrie, 2010).…”