Diversity and ecology of immature black flies in streams of Tambunan, Sabah

• Main Author: Nur Ashiqin Abdul Hamid
• Format: Thesis
• Language: English
• Published: 2018
• Subjects: SF Animal culture
• Online Access: https://eprints.ums.edu.my/id/eprint/26923/1/Diversity%20and%20ecology%20of%20immature%20black%20flies%20in%20streams%20of%20Tambunan%2C%20Sabah.pdf; https://eprints.ums.edu.my/id/eprint/26923/
• Institution: Universiti Malaysia Sabah

A study on the diversity and ecology of black flies towards the rainfall variations in Sabah was conducted for 12 months from October 2015 until September 2016 at Tambunan district. The objectives of this study were, i) to determine the black flies species composition in selected streams at Tambunan., ii) to determine the relationship between seasonal changes and the abundance of black flies pupae, and iii) to determine the relationship of water quality with the abundance of black flies pupae. There were six study sites located in the Tambunan district, Sabah. The sampling point were chosen according to their accessibility for collection and the presence of water flow. The frequency of field sampling was once every fortnight. During every field sampling, black flies larvae and pupae were collected from all substrates. The physico-chemical parameter of water quality such as stream depth, width, temperature, pH, dissolved oxygen (DO), velocity, conductivity and total dissolved solids (TDS) were also measured at the time of each collection. Rainfall data information for Tambunan District was obtained from Department of Meteorology Malaysia (Sabah Branch and Batu Gajah Agriculture station, Tambunan). Results from this study recorded seven species of black flies from three sub genus: Simulium, Gomphostilbia and Nevermania. The black flies species recorded were Simulium sabahense, Simulium keningauense, Simulium beludense, Simulium parahiyangum, Simulium sheilae, Simulium sp and Simulium aureohirtum. A total of 9689 individual of black flies pupae were sampled for a period of 12 months. The Shannon Weiner diversity index (H’) ranged between 0.06 to 1.65 which indicate low diversity of black flies in all the study sites. Sg Tambunan has the highest index value with 1.65 and the lowest diversity index value was recorded at Sg Lumondou, with the value of 0.06. The common species recorded in all sites were Simulium beludense, Simulium sabahense, Simulium keningauense followed by Simulium sp. Result shows that there were no significant differences in the mean number of black flies pupae sampled between wet and dry period (Kruskal Wallis test = 5, df = 23, p=0.419). The Spearman’s rank correlation test shows that there was a weak, negative correlation between rainfall variation and the abundance of black flies pupae (rs= -0.414, p=0.044). The Principal Analysis Component (PCA) analysis results indicated two principal components that have eigenvalue >1.0 and accounted 72.67% of the total variability of ecological factors among sampling sites. PC1 includes the stream depth, width, velocity, dissolved oxygen, conductivity and total dissolve solids, while the water pH was the only parameter in PC2. Spearman’s correlation test shows that there was a significant relationship between of physico-chemical parameter such as stream depth, stream width, velocity stream temperature, DO, TDS and conductivity with the total individual of black flies pupae with p value <0.05. Thus, it can be concluded that the rainfall variations and physico-chemical parameter have a significant relationship and influenced the abundance of black flies in Tambunan.