The influence of Formica exsecta ants on the abundance and diversity of other invertebrates in a private fragment of Tanzanias coastal forests

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Research Paper 03/09/2023
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The influence of Formica exsecta ants on the abundance and diversity of other invertebrates in a private fragment of Tanzanias coastal forests

Nuru Said Mohamed
J. Bio. Env. Sci.23( 3), 1-12, September 2023.
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This study was conducted in the fragment of Tanzania’s Coastal Forests (TCFs), which is one of the world’s ecoregions with varied endemic flora and fauna located on the coast of Indian Ocean. Its focus was on privately-owned TCFs, specifically a research and conservation centre of the late Prof. R.B.M Senzota since 1988. This fragment faces pressure from the surrounding population of more than seven million people of the Dar es salaam city, causing two visible habitat disturbances (disturbed and less disturbed) coupled with the outbreak of invasive species. The study assessed the influence of invasive Formica exsecta in varied disturbance levels and dry and wet seasons to invertebrate abundance and diversity. Pitfall trap, baited trap and dry leaf litter sifting were used in the invertebrate collection. The result show that this TCFs fragment to have higher invertebrate biodiversity with 484,481 individuals, 134 species, 87 families and 18 orders. Contrary to many findings, the disturbed habitat and dry season had higher abundance with lower diversity and species number compared to the less disturbed habitat and wet season with lower abundance but higher diversity and species number. Over dominance of aggressive Formica exsecta in the disturbed habitat and dry season by more than 90 present of all the individuals collected highly contributed to this variation as was also negative correlated to invertebrate abundances (r = -0.0012). The threat of the TCFs endangers enormous endemic wildlife; hence the need for the ultimate conservation efforts integrating both private and public-owned small and larger fragments before it was too late.


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