Livestock Browsing Threatens the Survival of Balanites aegyptiaca Seedlings and Saplings in Dinder Biosphere Reserve, Sudan

ABSTRACT

While the impact of livestock grazing has been frequently assessed for grasses, little is known about how livestock affects tree seedlings and saplings. We explored the effects of goat, cattle and camel browsing on the survival of Balanites aegyptiaca seedlings and saplings, a broadleaved evergreen tree species indigenous to Sudan, in Dinder Biosphere Reserve-Sudan (DBR). We used a stratified sampling design with four sites: GOA (mainly browsed by goats), CAT and CAM being mainly browsed by cattle and camels, respectively, while CON was a control area without any livestock browsing. We tested the survival, mortality and recovery of seedlings and saplings across different sites. Our results revealed that mortalities of seedlings in GOA were almost four times higher than that of CAM and CON and twice that of CAT (F_3,196 = 100.39, P < .001). Further, sapling mortality was three times higher in GOA than that observed in CAT and CON (F_3,196 = 73.4, P < .001). We found that seedlings recover better than saplings, and, unexpectedly, goat browsing severely affected the natural regeneration of B. aegyptiaca in DBR compared to other livestock species. Our study findings contribute to sustainable forest management and show that particularly goat browsing needs to be suppressed for conservation of vulnerable tree species.

KEYWORDS:

• Herbivory
• natural regeneration
• protected area
• rangelands
• woodland

Acknowledgments

The authors would like to thank University of Gezira for research facilities and logistic support during fieldwork, and RUFORUM for GTA scholarship. The authors also acknowledge and thank Prof. Hisham M. M. Tahir (Department of Forestry, College of Natural Resources and Environmental Studies, University of Bahri, Sudan), Dr Tawhida A. Yousif (Faculty of Urban Sciences, Alzaiem Alazhari University, Sudan), Dr Difo V. Harouna (Faculty of Sciences, University of Maroua, Cameroon), and Dr Kafula Chisanga (Zambia Agriculture Research Institute, Zambia) for their help during the data analysis stage. We also thank the peer reviewers of the journal of sustainable forestry who their comments helped us improved the paper and reshaped it.

Declaration of interest statement

The authors declare no conflict of interest.

Additional information

Funding

This research was supported by the Rufford small grant for nature conservation (Rufford Foundation) under grant number 30315-1, and the Regional Universities Forum for Capacity Building in Agriculture, Graduate Teaching Assistant Programme, Doctoral Regional Research Grant (RU/GTA/DRG grant) with grant number RU/2020/GTA/DRG/036.