Research Articles (Zoology and Entomology)http://hdl.handle.net/2263/17402024-03-29T05:16:27Z2024-03-29T05:16:27ZThe elusive echo : the mystery of Africa’s sparse bat fossil recordPretorius, Mariettehttp://hdl.handle.net/2263/954022024-03-28T22:46:28Z2024-03-01T00:00:00ZThe elusive echo : the mystery of Africa’s sparse bat fossil record
Pretorius, Mariette
SIGNIFICANCE : The scarcity of bat fossils in Africa poses a significant challenge to both scientific understanding and current
conservation efforts. While this article engages in informed speculation regarding the reasons behind this
scarcity, it does not lessen the importance of the issue. Without a robust fossil record, tracing the evolutionary
history, biological adaptations, and historical ecological roles of bats becomes difficult. Understanding their
past is instrumental in mitigating current threats to bats like habitat loss and climate change. Thus, the
intriguing lack of a comprehensive fossil record not only limits scientific inquiry but also hinders effective
conservation measures.
2024-03-01T00:00:00ZBest practices for colony management : a neglected aspect for improving honey bee colony health and productivity in AfricaNganso, Beatrice T.Soroker, VictoriaOsabutey, Angelina F.Pirk, Christian Walter WernerJohansson, TinoElie, NtirenganyaOtieno-Ayayo, Z. NgaloIbrahim, Mohammed M.Ndungu, N.N.Ayalew, WorknehWubie, Abebe J.Taboue, Geraud C. TasseFameni, Sidonie T.Bobadoye, Bridget O.Assefa, FreweiniSubramanian, Sevganhttp://hdl.handle.net/2263/953412024-03-25T22:49:23Z2024-01-01T00:00:00ZBest practices for colony management : a neglected aspect for improving honey bee colony health and productivity in Africa
Nganso, Beatrice T.; Soroker, Victoria; Osabutey, Angelina F.; Pirk, Christian Walter Werner; Johansson, Tino; Elie, Ntirenganya; Otieno-Ayayo, Z. Ngalo; Ibrahim, Mohammed M.; Ndungu, N.N.; Ayalew, Workneh; Wubie, Abebe J.; Taboue, Geraud C. Tasse; Fameni, Sidonie T.; Bobadoye, Bridget O.; Assefa, Freweini; Subramanian, Sevgan
Apiculture has a well-recognized role in enhancing food security by pollination services around the globe. Besides, apiculture is an extremely valuable income-generating and job-creating activity for millions of men, women, and youths across Africa through trade of hive products, especially honey. However, the yields of honey and other hive products are apparently below the optimum in most African countries. In this review, we discuss the characteristics of the local honey bee subspecies and current apicultural practices in relation to the factors that can potentially influence colony productivity. We highlight some potential factors affecting colony management and productivity and discuss research gaps that need to be addressed in order to improve the profitability and the sustainability of apiculture on a large scale in Africa.
2024-01-01T00:00:00ZCounter-strategies to infanticide : the importance of cubs in determining lion habitat selection and social interactionsDejeante, RomainLoveridge, Andrew J.Macdonald, David W.Madhlamoto, DaphineValeix, MarionChamaille-Jammes, Simonhttp://hdl.handle.net/2263/953402024-03-25T22:48:27Z2024-02-01T00:00:00ZCounter-strategies to infanticide : the importance of cubs in determining lion habitat selection and social interactions
Dejeante, Romain; Loveridge, Andrew J.; Macdonald, David W.; Madhlamoto, Daphine; Valeix, Marion; Chamaille-Jammes, Simon
Animal social and spatial behaviours are inextricably linked. Animal movements are driven by environmental factors and social interactions. Habitat structure and changing patterns of animal space use can also shape social interactions.
Animals adjust their social and spatial behaviours to reduce the risk of offspring mortality. In territorial infanticidal species, two strategies are possible for males: they can stay close to offspring to protect them against rivals (infant-defence hypothesis) or patrol the territory more intensively to prevent rival intrusions (territorial-defence hypothesis). Here, we tested these hypotheses in African lions (Panthera leo) by investigating how males and females adjust their social and spatial behaviours in the presence of offspring.
We combined datasets on the demography and movement of lions, collected between 2002 and 2016 in Hwange National Park (Zimbabwe), to document the presence of cubs (field observations) and the simultaneous movements of groupmates and competitors (GPS tracking).
We showed a spatial response of lions to the presence of offspring, with females with cubs less likely to select areas close to waterholes or in the periphery of the territory than females without cubs. In contrast, these areas were more selected by males when there were cubs in the pride. We also found social responses. Males spent more time with females as habitat openness increased but the presence of cubs in the pride did not influence the average likelihood of observing males with females. Furthermore, rival males relocated further after an encounter with pride males when cubs were present in the prides, suggesting that the presence of cubs leads to a more vigorous repulsion of competitors. Males with cubs in their pride were more likely to interact with male competitors on the edge of the pride's home range and far from the waterholes, suggesting that they are particularly assiduous in detecting and repelling rival males during these periods.
In general, the strategies to avoid infanticide exhibited by male lions supported the territorial-defence hypothesis. Our study contributes to answer the recent call for a behavioural ecology at the spatial-social interface.
DATA AVAILABILITY STATEMENT : Data available from the figshare repository: https://doi.org/10.6084/m9.figshare.24786867.v2 (Dejeante et al., 2023).; APPENDIX S1. TABLE S1.1. Coefficients (β) and standard errors (SE) for selection ratio model of lioness habitat selection for distance to water (WATER), open habitats (OPEN), and distance to the home range centroid (HR) accounting for the presence/absence of cubs within the pride (CUB; without cub = 0, with cub = 1).
TABLE S1.2. Coefficients (β) and standard errors (SE) for selection ratio models of pride male habitat selection for distance to water (WATER), open habitats (OPEN), and distance to the home range centroid (HR) accounting for the presence/absence of cubs within the pride (CUB; without cub = 0, with cub = 1) and for the presence/absence of females in proximity (FEM; without female = 0, with female = 1).
TABLE S1.3. Coefficients (β) and standard errors (SE) for the GLMMs testing the influence of the mean habitat openness (OPEN) and the presence of cubs (CUB) on (a) the percentage of time pride males spent in proximity with pride females, (b) the frequencies and (c) the duration of male-female proximity events.
TABLE S1.4. Frequency of pride male-competitor male proximity events according to the presence of cubs within the pride (CUB) and the overlap of the utilization distributions of pride and competitor males (UD overlap). We run a log-linear regression adding a random intercept with dyad identity.
TABLE S1.5. Spatial characteristics of proximity events between pride males and competitor males.
TABLE S1.6. Outcome characteristics of proximity events between pride males and competitor males.; APPENDIX S2. Distance-based definition of proximity events, used as proxies for social interactions.
FIGURE S2.1. Methods to identify male-female interactions: comparison of male-female proximity events estimated by an univariate hidden-markov model based on the dyad distance, and estimated by a distance threshold from 100 to 5 km.
FIGURE S2.2. Distance-threshold sensitivity of the duration and frequency measures describing the temporal dynamics of male-female (a, b) and male-male proximity events (c, d).; APPENDIX S3. Pride male-female association.
FIGURE S3.1. Locations and core home ranges of pride males (blue) and females (red), delineated from the 50% utilization distribution of a kernel-based home range estimate, using the adehabitatHR package (Calenge 2007).
FIGURE S3.2. Temporal dynamic of pride male and female proximity events as a function to the size of the female core home range and to the proportion of habitats close to waterholes (i.e. <1 km) within it, according to the presence (blue) and absence (orange) of cubs within the pride.
TABLE S3.1. Coefficients (β) and standard errors (SE) for selection ratio model of lioness habitat selection for distance to water (WATER), open habitats (OPEN), and distance to the home range centroid (HR) accounting for the presence/absence of cubs within the pride (CUB; without cub = 0, with cub = 1).
TABLE S3.2. Coefficients (β) and standard errors (SE) for selection ratio models of pride male habitat selection for distance to water (WATER), open habitats (OPEN), and distance to the home range centroid (HR) accounting for the presence/absence of cubs within the pride (CUB; without cub = 0, with cub = 1) and for the presence/absence of females in proximity (FEM; without female = 0, with female = 1).
TABLE S3.3. Coefficients (β) and standard errors (SE) for the GLMMs testing the influence of the mean habitat openness (OPEN) and the presence of cubs (CUB) on (a) the percentage of time pride males spent in proximity with pride females, (b) the frequencies and (c) the duration of male-female proximity events.; APPENDIX S4. Pride male—competitor male association.
FIGURE S4.1. GPS locations of female (green), male (blue) and competitor (red) lions, for each of the 30 studied triads.
FIGURE S4.2. Relationship between the frequencies of proximity events between pride males and competitor males and the overlap of their utilization distribution (i.e. Bhattacharyya's affinity index) according to the presence (blue) and absence (orange) of cubs in the pride.
TABLE S4.1. Frequency of pride male-competitor male proximity events according to the presence of cubs within the pride (CUB) and the overlap of the utilization distributions of pride and competitor males (UD overlap).
TABLE S4.2. Spatial characteristics of proximity events between pride males and competitor males.
TABLE S4.3. Outcome characteristics of proximity events between pride males and competitor males.
2024-02-01T00:00:00ZThe relationship between mammalian burrow abundance and bankrupt bush (Seriphium plumosum) encroachmentOosthuysen, MorneStrauss, W. MaartinSomers, Michael J.http://hdl.handle.net/2263/953102024-03-20T22:45:42Z2023-07-17T00:00:00ZThe relationship between mammalian burrow abundance and bankrupt bush (Seriphium plumosum) encroachment
Oosthuysen, Morne; Strauss, W. Maartin; Somers, Michael J.
BACKGROUND : Much of the Grassland Biome in South Africa is prone to shrub encroachment, leading to loss of ecosystem services, habitat heterogeneity and species diversity. Burrowing mammals are an important component of grasslands as these animals create microhabitats for other taxa, including smaller mammal species, birds, reptiles and invertebrates. However, our understanding of how shrub encroachment affects burrowing mammals is poor. OBJECTIVES : Here we assessed the relationship between burrow abundance and bankrupt bush, Seriphium plumosum, encroachment as well as burrowing mammal diversity in bankrupt bush encroached and non-encroached grasslands METHOD: Shrub density, medium and large mammal burrow abundance and density were measured in 24 encroached and 24 non-encroached areas randomly selected in the Telperion Nature Reserve, Mpumalanga, South Africa. In addition, burrowing mammal diversity was assessed using camera traps in a subset of six encroached and six non-encroached areas. RESULTS : Our results show that the abundance and density of medium and large burrows were significantly lower in encroached areas than in non-encroached areas (p = 0.011 and p < 0.001, respectively). The relationship between burrow abundance and bankrupt bush encroachment was negative (rho = -0.456, p = 0.001). However, burrowing mammal diversity had no significant difference between encroached and non-encroached areas. CONCLUSION : Our data, therefore, suggest that with increasing bankrupt bush encroachment and a decreased abundance in burrowing mammal ecosystem services, a negative effect will occur on burrowing mammal communities, leading to the reduction in species-specific habitat heterogeneity and possibly animal biodiversity.
2023-07-17T00:00:00Z