High mortality poses a serious threat to sustainable conservation of the African elephant (Loxodo... more High mortality poses a serious threat to sustainable conservation of the African elephant (Loxodonta africana). Using detected carcass data collected by the Kenya Wildlife Service (KWS) during 1992-2017, we analyze temporal and spatial variation in elephant mortality in Kenya. We investigate the major mortality causes and means used to kill elephants, carcass category, tusk recovery status, variation in mortality with elephant age and sex classes, differences between inside and outside protected areas (PAs), the Proportion of Illegally Killed Elephants (PIKE) and the overall mortality rate (MR — the number of dead/number of live elephants in a given year). In total 9,182 elephant deaths were recorded during the 26 years. Elephant mortality increased over time and was attributed primarily to natural (33.1%) and human-related causes, particularly ivory poaching (31.5%) and human-elephant conflicts (19.9%). Elephant mortality varied across Kenya’s 47 counties in correspondence with var...
Rail and road infrastructure is essential for economic growth and development but can cause a gra... more Rail and road infrastructure is essential for economic growth and development but can cause a gradual loss in biodiversity and degradation of ecosystem function and services. We assessed the influence of underpass dimensions, fencing, proximity to water and roads, Normalized Difference Vegetation Index (NDVI), presence of other species and livestock on underpass use by large and medium-sized mammals. Results revealed hyenas and leopards used the underpasses more than expected whereas giraffes and antelopes used the underpasses less than expected. Generalized linear mixed-effects models revealed that underpass height influenced use by wildlife, with several species preferring to use taller underpasses. Electric fencing increased underpass use by funneling species towards underpasses, except for elephants and black-backed jackal for which it reduced underpass passage. We also found that the use of underpasses by livestock reduced the probability of use by nearly 50% for wildlife speci...
Supplemental Online Materials and Appendices for "Ecological fidelity of functional traits b... more Supplemental Online Materials and Appendices for "Ecological fidelity of functional traits based on species presence-absence in a modern mammalian bone assemblage (Amboseli, Kenya).
Arabuko-Sokoke Forest (ASF) found in Kenya, is the largest coastal forest in eastern Africa. The ... more Arabuko-Sokoke Forest (ASF) found in Kenya, is the largest coastal forest in eastern Africa. The forest is a biodiversity hotspot of global conservation importance for harbouring many endemic and globally threatened species. We reviewed published literature and used field reports of different mammal expeditions undertaken in ASF to compile a comprehensive checklist of mammal species known to occur in Kenya. A total of 73 species of mammals have been recorded in ASF. The checklist contains the current accepted common and scientific names of mammal species provided by authors who published the six volumes of the Mammals of Africa. The checklist is expected to be updated with additions of new species in future especially when additional surveys and the taxonomic status of small mammals (e.g., bats, shrews and rodents) becomes better understood.
International Journal of Biodiversity and Conservation, 2019
Human-wildlife conflicts (HWC) can cause substantial losses. Compensation for such losses is esse... more Human-wildlife conflicts (HWC) can cause substantial losses. Compensation for such losses is essential to foster positive community attitudes toward wildlife conservation. Monetary compensation for the loss of human life, injury, crop and property damage, or livestock depredation by wildlife is a common strategy for mitigating HWC. We analyzed inter-specific, spatial, inter-annual and seasonal variation in human-wildlife conflicts, conflict outcome and the associated monetary costs of compensation in Kenya during 2007-2016. A total of 18,794 compensation claims were filed with the Kenya National Compensation Scheme (KNCS) during 2007 - 2016. Snakes made the greatest contribution to the total cases (44.8%, = 8,423), human fatalities (43.1%, = 614) and human injuries (76.9%, = 7,772). Elephant was the second leading conflict species (22.3%, = 4,181) and was responsible for 18.8% ( = 266) of human deaths and over 75% of crop and property damage. Spotted hyena, leopard and lion caused 85% of livestock predation cases. The intensity and outcome of conflicts varied across counties such that most human fatalities occurred in arid Tana River and Wajir counties, whereas most human injuries occurred in Kitui and Wajir counties. The intensity of conflicts was strongly influenced by the agro-climatic potential and percentage of a county under protection, rainfall and temperature and their interactions. In consequence, crop damage was highest in counties with high agricultural potential (Meru and Taita Taveta) but livestock predation was highest in counties with large protected areas (Samburu and Taita Taveta). Human fatality and injury were higher among males than females and adults than children. Over the 10-year period, the Kenya Government spent about 3 billion Kenya shillings on compensation of about 30% of all filed claims. Compensation schemes require sustainable funding mechanisms and effective administration to minimize negative unintended consequences. Key words: Human-wildlife conflicts, compensation, snake bites, attack on humans, livestock predation, crop raiding, rainfall, temperature, human population growth.
Comparisons between modern death assemblages and their source communities have demonstrated fidel... more Comparisons between modern death assemblages and their source communities have demonstrated fidelity to species diversity across a variety of environments and taxonomic groups. However, differential species preservation and collection (including body-size bias) in both modern and fossil death assemblages may still skew the representation of other important ecological characteristics. Here, we move beyond live-dead taxonomic fidelity and focus on the recovery of functional ecology (how species interact with their ecosystem) at the community level for a diverse non-volant mammal community (87 species; Amboseli, Kenya). We use published literature to characterize species, using four functional traits and their associated categorical attributes (i) dietary mode (11 attributes; e.g., browser, grazer), (ii) preferred feeding habitat (16 attributes; e.g., grassland, woodland), (iii) preferred sheltering habitat (17 attributes; e.g., grassland, underground cavity), and (iv) activity time (7 attributes; e.g., diurnal, nocturnal, nocturnally dominated crepuscular). For each functional ecological trait we compare the death assemblage's recovered richness and abundance structure of constituent functional attributes with those of the source community, using Jaccard similarity, Spearman's rho, and the Probability of Interspecific Encounter (evenness). We use Monte Carlo simulations to evaluate whether these empirical comparisons are significantly different from expectations calculated from randomized sampling of species from the source community. Results indicate that although the Amboseli death assemblage is significantly overrepresented by large-bodied species relative to the Amboseli source community, it captures many functional dimensions of the ecosystem within expectations of a randomized collection of species. Additional resampling simulations and logistic regressions further illustrate that the size bias inherent to the Amboseli death assemblage is not a major driver of deviations between the functional ecological properties of the death assemblage and its source community. Finally, the Amboseli death assemblage also enhances our understanding of the mammal community by adding nine species and two functional attributes previously unknown from the ecosystem
Roadkill is one of the highest causes of wildlife mortality and is of global conservation concern... more Roadkill is one of the highest causes of wildlife mortality and is of global conservation concern. Most roadkill studies have focused on wildlife in developed countries such as the United States of America and temperate biomes, but there are limited data for the impacts of roads on wildlife in the African tropics, where road infrastructure development is projected to grow rapidly in natural environments and conservation areas. The Tsavo Conservation Area is an important biodiversity hotspot in eastern Kenya and is bisected by a major highway and railways that connect the port of Mombasa to the interior. Along this infrastructure corridor, roadkill was recorded for 164 days over an 11-year period (2007–2018). In total, 1,436 roadkill were recorded from 13,008 km driven of a 164.42 km Nairobi-Mombasa road representing 0.11 collisions per kilometer. The majority of roadkill were small to medium sized mammals (<15kg) (53%; n = 756), whereas birds comprised 32% (n = 460), reptiles 10%...
Human-wildlife conflict (HWC) is a widespread and persistent challenge to conservation. However, ... more Human-wildlife conflict (HWC) is a widespread and persistent challenge to conservation. However, relatively few studies have thus far examined long-term monitoring data to quantify how the type, and severity of HWC varies across species, seasons, years and ecosystems. Here, we examine human-wildlife conflicts in Tsavo and Maasai Mara, two premier wildlife conservation areas in Kenya. Using Kenya Wildlife Service (KWS) data (2001-2016), we show that both the type and severity of conflicts vary among species such that the African elephant (Loxodonta africana), is the leading conflict species in both the Tsavo (64.3%, n= 30664) and Mara (47.0%, n=12487) ecosystems. The next four most notorious conflict animals, in decreasing order, are nonhuman primates (Tsavo 11.4%, n=3502; Mara 11.8%, n=1473), African buffalo (Syncerus caffer, Tsavo 5.5%, n=1676; Mara 11.3%, n=1410), lion (Panthera leo,Tsavo 3.6%, n=1107; Mara 3.3%, n=416) and spotted hyena (Crocuta crocuta, Tsavo 2.4%, n=744; Mara 5...
High mortality poses a serious threat to sustainable conservation of the African elephant (Loxodo... more High mortality poses a serious threat to sustainable conservation of the African elephant (Loxodonta africana). Using detected carcass data collected by the Kenya Wildlife Service (KWS) during 1992-2017, we analyze temporal and spatial variation in elephant mortality in Kenya. We investigate the major mortality causes and means used to kill elephants, carcass category, tusk recovery status, variation in mortality with elephant age and sex classes, differences between inside and outside protected areas (PAs), the Proportion of Illegally Killed Elephants (PIKE) and the overall mortality rate (MR — the number of dead/number of live elephants in a given year). In total 9,182 elephant deaths were recorded during the 26 years. Elephant mortality increased over time and was attributed primarily to natural (33.1%) and human-related causes, particularly ivory poaching (31.5%) and human-elephant conflicts (19.9%). Elephant mortality varied across Kenya’s 47 counties in correspondence with var...
Rail and road infrastructure is essential for economic growth and development but can cause a gra... more Rail and road infrastructure is essential for economic growth and development but can cause a gradual loss in biodiversity and degradation of ecosystem function and services. We assessed the influence of underpass dimensions, fencing, proximity to water and roads, Normalized Difference Vegetation Index (NDVI), presence of other species and livestock on underpass use by large and medium-sized mammals. Results revealed hyenas and leopards used the underpasses more than expected whereas giraffes and antelopes used the underpasses less than expected. Generalized linear mixed-effects models revealed that underpass height influenced use by wildlife, with several species preferring to use taller underpasses. Electric fencing increased underpass use by funneling species towards underpasses, except for elephants and black-backed jackal for which it reduced underpass passage. We also found that the use of underpasses by livestock reduced the probability of use by nearly 50% for wildlife speci...
Supplemental Online Materials and Appendices for "Ecological fidelity of functional traits b... more Supplemental Online Materials and Appendices for "Ecological fidelity of functional traits based on species presence-absence in a modern mammalian bone assemblage (Amboseli, Kenya).
Arabuko-Sokoke Forest (ASF) found in Kenya, is the largest coastal forest in eastern Africa. The ... more Arabuko-Sokoke Forest (ASF) found in Kenya, is the largest coastal forest in eastern Africa. The forest is a biodiversity hotspot of global conservation importance for harbouring many endemic and globally threatened species. We reviewed published literature and used field reports of different mammal expeditions undertaken in ASF to compile a comprehensive checklist of mammal species known to occur in Kenya. A total of 73 species of mammals have been recorded in ASF. The checklist contains the current accepted common and scientific names of mammal species provided by authors who published the six volumes of the Mammals of Africa. The checklist is expected to be updated with additions of new species in future especially when additional surveys and the taxonomic status of small mammals (e.g., bats, shrews and rodents) becomes better understood.
International Journal of Biodiversity and Conservation, 2019
Human-wildlife conflicts (HWC) can cause substantial losses. Compensation for such losses is esse... more Human-wildlife conflicts (HWC) can cause substantial losses. Compensation for such losses is essential to foster positive community attitudes toward wildlife conservation. Monetary compensation for the loss of human life, injury, crop and property damage, or livestock depredation by wildlife is a common strategy for mitigating HWC. We analyzed inter-specific, spatial, inter-annual and seasonal variation in human-wildlife conflicts, conflict outcome and the associated monetary costs of compensation in Kenya during 2007-2016. A total of 18,794 compensation claims were filed with the Kenya National Compensation Scheme (KNCS) during 2007 - 2016. Snakes made the greatest contribution to the total cases (44.8%, = 8,423), human fatalities (43.1%, = 614) and human injuries (76.9%, = 7,772). Elephant was the second leading conflict species (22.3%, = 4,181) and was responsible for 18.8% ( = 266) of human deaths and over 75% of crop and property damage. Spotted hyena, leopard and lion caused 85% of livestock predation cases. The intensity and outcome of conflicts varied across counties such that most human fatalities occurred in arid Tana River and Wajir counties, whereas most human injuries occurred in Kitui and Wajir counties. The intensity of conflicts was strongly influenced by the agro-climatic potential and percentage of a county under protection, rainfall and temperature and their interactions. In consequence, crop damage was highest in counties with high agricultural potential (Meru and Taita Taveta) but livestock predation was highest in counties with large protected areas (Samburu and Taita Taveta). Human fatality and injury were higher among males than females and adults than children. Over the 10-year period, the Kenya Government spent about 3 billion Kenya shillings on compensation of about 30% of all filed claims. Compensation schemes require sustainable funding mechanisms and effective administration to minimize negative unintended consequences. Key words: Human-wildlife conflicts, compensation, snake bites, attack on humans, livestock predation, crop raiding, rainfall, temperature, human population growth.
Comparisons between modern death assemblages and their source communities have demonstrated fidel... more Comparisons between modern death assemblages and their source communities have demonstrated fidelity to species diversity across a variety of environments and taxonomic groups. However, differential species preservation and collection (including body-size bias) in both modern and fossil death assemblages may still skew the representation of other important ecological characteristics. Here, we move beyond live-dead taxonomic fidelity and focus on the recovery of functional ecology (how species interact with their ecosystem) at the community level for a diverse non-volant mammal community (87 species; Amboseli, Kenya). We use published literature to characterize species, using four functional traits and their associated categorical attributes (i) dietary mode (11 attributes; e.g., browser, grazer), (ii) preferred feeding habitat (16 attributes; e.g., grassland, woodland), (iii) preferred sheltering habitat (17 attributes; e.g., grassland, underground cavity), and (iv) activity time (7 attributes; e.g., diurnal, nocturnal, nocturnally dominated crepuscular). For each functional ecological trait we compare the death assemblage's recovered richness and abundance structure of constituent functional attributes with those of the source community, using Jaccard similarity, Spearman's rho, and the Probability of Interspecific Encounter (evenness). We use Monte Carlo simulations to evaluate whether these empirical comparisons are significantly different from expectations calculated from randomized sampling of species from the source community. Results indicate that although the Amboseli death assemblage is significantly overrepresented by large-bodied species relative to the Amboseli source community, it captures many functional dimensions of the ecosystem within expectations of a randomized collection of species. Additional resampling simulations and logistic regressions further illustrate that the size bias inherent to the Amboseli death assemblage is not a major driver of deviations between the functional ecological properties of the death assemblage and its source community. Finally, the Amboseli death assemblage also enhances our understanding of the mammal community by adding nine species and two functional attributes previously unknown from the ecosystem
Roadkill is one of the highest causes of wildlife mortality and is of global conservation concern... more Roadkill is one of the highest causes of wildlife mortality and is of global conservation concern. Most roadkill studies have focused on wildlife in developed countries such as the United States of America and temperate biomes, but there are limited data for the impacts of roads on wildlife in the African tropics, where road infrastructure development is projected to grow rapidly in natural environments and conservation areas. The Tsavo Conservation Area is an important biodiversity hotspot in eastern Kenya and is bisected by a major highway and railways that connect the port of Mombasa to the interior. Along this infrastructure corridor, roadkill was recorded for 164 days over an 11-year period (2007–2018). In total, 1,436 roadkill were recorded from 13,008 km driven of a 164.42 km Nairobi-Mombasa road representing 0.11 collisions per kilometer. The majority of roadkill were small to medium sized mammals (<15kg) (53%; n = 756), whereas birds comprised 32% (n = 460), reptiles 10%...
Human-wildlife conflict (HWC) is a widespread and persistent challenge to conservation. However, ... more Human-wildlife conflict (HWC) is a widespread and persistent challenge to conservation. However, relatively few studies have thus far examined long-term monitoring data to quantify how the type, and severity of HWC varies across species, seasons, years and ecosystems. Here, we examine human-wildlife conflicts in Tsavo and Maasai Mara, two premier wildlife conservation areas in Kenya. Using Kenya Wildlife Service (KWS) data (2001-2016), we show that both the type and severity of conflicts vary among species such that the African elephant (Loxodonta africana), is the leading conflict species in both the Tsavo (64.3%, n= 30664) and Mara (47.0%, n=12487) ecosystems. The next four most notorious conflict animals, in decreasing order, are nonhuman primates (Tsavo 11.4%, n=3502; Mara 11.8%, n=1473), African buffalo (Syncerus caffer, Tsavo 5.5%, n=1676; Mara 11.3%, n=1410), lion (Panthera leo,Tsavo 3.6%, n=1107; Mara 3.3%, n=416) and spotted hyena (Crocuta crocuta, Tsavo 2.4%, n=744; Mara 5...
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