Small-mammal abundance and species diversity: land use and seasonal influences in the Serengeti Ecosystem, Tanzania

Land use, habitat suitability, and seasonality can fundamentally shape small-mammal abundance, species richness, diversity, evenness, and composition. However, how these characteristics of small mammals are determined by land use, habitat type, and rainfall seasonality is still poorly understood for...

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Main Authors: Monica T. Shilereyo, Flora J. Magige, Joseph O. Ogutu, Eivin Røskaft
Format: Article
Language:English
Published: Frontiers Media S.A. 2023-07-01
Series:Frontiers in Conservation Science
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/fcosc.2023.981424/full
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author Monica T. Shilereyo
Monica T. Shilereyo
Flora J. Magige
Joseph O. Ogutu
Eivin Røskaft
author_facet Monica T. Shilereyo
Monica T. Shilereyo
Flora J. Magige
Joseph O. Ogutu
Eivin Røskaft
author_sort Monica T. Shilereyo
collection DOAJ
description Land use, habitat suitability, and seasonality can fundamentally shape small-mammal abundance, species richness, diversity, evenness, and composition. However, how these characteristics of small mammals are determined by land use, habitat type, and rainfall seasonality is still poorly understood for most ecosystems. We analyze how land use (protection in a national park, pastoralism, and crop agriculture), habitat type, and rainfall seasonality influence small-mammal relative abundance, species richness, and diversity in the Tanzania Serengeti Ecosystem. We used 141 live traps to capture 612 small mammals in the wet and dry seasons of 2017 and 2018. Relative abundance was higher in the pastoral land than in the park or agricultural land and in the dry season in all the three land use types. Species richness and diversity were highest in the park, middling in the agricultural land, and lowest in the pastoral land. The high relative abundance in the pastoral land was primarily due to the numerical dominance of two generalist species in the shrubland (grass rat Arvicanthis niloticus) and cropland (multimammate rat Mastomys natalensis), resulting in low species richness and diversity. High species richness and diversity in the park indicate high habitat heterogeneity, whereas high species diversity in the agricultural land during the dry season reflects high food availability during and soon after harvests. Thus, human activities apparently exert deleterious effects on some specialist small mammals as a result of reduced habitat heterogeneity while promoting the abundance of some generalist species in African savanna ecosystems. However, increased abundance of generalist species reduces small mammal species diversity while increasing the risk of human–small mammal conflicts. We offer several testable hypotheses motivated by our results.
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spelling doaj.art-e0e8f6aa994349ed9307827edf62fb192023-07-25T17:09:14ZengFrontiers Media S.A.Frontiers in Conservation Science2673-611X2023-07-01410.3389/fcosc.2023.981424981424Small-mammal abundance and species diversity: land use and seasonal influences in the Serengeti Ecosystem, TanzaniaMonica T. Shilereyo0Monica T. Shilereyo1Flora J. Magige2Joseph O. Ogutu3Eivin Røskaft4Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, NorwayDepartment of Zoology and Wildlife Conservation, University of Dar es Salaam, Dar es Salaam, TanzaniaDepartment of Zoology and Wildlife Conservation, University of Dar es Salaam, Dar es Salaam, TanzaniaBiostatistics Unit, Institute for Crop Science, University of Hohenheim, Stuttgart, GermanyDepartment of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, NorwayLand use, habitat suitability, and seasonality can fundamentally shape small-mammal abundance, species richness, diversity, evenness, and composition. However, how these characteristics of small mammals are determined by land use, habitat type, and rainfall seasonality is still poorly understood for most ecosystems. We analyze how land use (protection in a national park, pastoralism, and crop agriculture), habitat type, and rainfall seasonality influence small-mammal relative abundance, species richness, and diversity in the Tanzania Serengeti Ecosystem. We used 141 live traps to capture 612 small mammals in the wet and dry seasons of 2017 and 2018. Relative abundance was higher in the pastoral land than in the park or agricultural land and in the dry season in all the three land use types. Species richness and diversity were highest in the park, middling in the agricultural land, and lowest in the pastoral land. The high relative abundance in the pastoral land was primarily due to the numerical dominance of two generalist species in the shrubland (grass rat Arvicanthis niloticus) and cropland (multimammate rat Mastomys natalensis), resulting in low species richness and diversity. High species richness and diversity in the park indicate high habitat heterogeneity, whereas high species diversity in the agricultural land during the dry season reflects high food availability during and soon after harvests. Thus, human activities apparently exert deleterious effects on some specialist small mammals as a result of reduced habitat heterogeneity while promoting the abundance of some generalist species in African savanna ecosystems. However, increased abundance of generalist species reduces small mammal species diversity while increasing the risk of human–small mammal conflicts. We offer several testable hypotheses motivated by our results.https://www.frontiersin.org/articles/10.3389/fcosc.2023.981424/fullsmall mammalsrelative abundancespecies diversityrainfall seasonalityland useSerengeti ecosystem
spellingShingle Monica T. Shilereyo
Monica T. Shilereyo
Flora J. Magige
Joseph O. Ogutu
Eivin Røskaft
Small-mammal abundance and species diversity: land use and seasonal influences in the Serengeti Ecosystem, Tanzania
Frontiers in Conservation Science
small mammals
relative abundance
species diversity
rainfall seasonality
land use
Serengeti ecosystem
title Small-mammal abundance and species diversity: land use and seasonal influences in the Serengeti Ecosystem, Tanzania
title_full Small-mammal abundance and species diversity: land use and seasonal influences in the Serengeti Ecosystem, Tanzania
title_fullStr Small-mammal abundance and species diversity: land use and seasonal influences in the Serengeti Ecosystem, Tanzania
title_full_unstemmed Small-mammal abundance and species diversity: land use and seasonal influences in the Serengeti Ecosystem, Tanzania
title_short Small-mammal abundance and species diversity: land use and seasonal influences in the Serengeti Ecosystem, Tanzania
title_sort small mammal abundance and species diversity land use and seasonal influences in the serengeti ecosystem tanzania
topic small mammals
relative abundance
species diversity
rainfall seasonality
land use
Serengeti ecosystem
url https://www.frontiersin.org/articles/10.3389/fcosc.2023.981424/full
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