Iological Characteristics in Habitats of High and Low Presence of Anopheline Larvae in Hexanoyl-Tyr-Ile-Ahx-NH2 site western Kenya HighlandsBryson A. Ndenga1,2*, Jemimah A. Simbauni1, Jenard P. Mbugi1, Andrew K. Githeko1 Department of Zoological Sciences, Kenyatta University, Nairobi, Kenya, 2 Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, KenyaAbstractBackground: Characteristics of aquatic habitats determine whether mosquitoes will oviposit, hatch, develop, pupate and successfully emerge into adults or not, thus influencing which mosquito species will occupy a habitat. This study determined whether physiochemical and biological characteristics differ between habitats with high and low presence of anopheline larvae. Methods: Physical, chemical and biological characteristics were evaluated in selected habitats twice per month within three highland valleys in western Kenya. Aquatic macro-organisms were sampled using a sweep-net. Colorimetric methods were used to determine levels of iron, phosphate, nitrate, ammonium and nitrite in water samples. Generalized Estimating Equations (GEE) was used to compare parameters between the two categories of anopheline presence. Results: Habitats with high anopheline presence had greater abundance of mosquito aquatic stages and tadpoles and two times more levels of nitrate in water, whereas habitats with low anopheline presence had wider biofilm cover and higher levels of iron in water. Conclusion: Habitats of high and low presence of anopheline larvae, which differed in a number of physical, chemical and biological characteristics, were identified in valleys within western Kenya highlands. Differences in habitat characteristics are critical in determining the number of anopheline larvae that will fully develop and emerge into adults.Citation: Ndenga BA, Simbauni JA, Mbugi JP, Githeko AK (2012) Physical, Chemical and Biological Characteristics in Habitats of High and Low Presence of Anopheline Larvae in Western Kenya Highlands. PLoS ONE 7(10): e47975. doi:10.1371/journal.pone.0047975 Editor: Olle Terenius, Swedish University of Agricultural Sciences, Sweden Received May 28, 2012; Accepted September 19, 2012; Published October 23, 2012 Copyright: ?2012 Ndenga et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This work was funded by the World Health Organization (WHO) Special Programme for Research and Training in Tropical Diseases (TDR)-Research Training Grant (RTG) and Valent BioSciences Corporation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: This research study received part of its funding from a buy AICAR commercial source “Valent BioSciences Corporation”. The authors declare that they have no competing interest relating to employment, consultancy, patents, and products in development or on the market. This does not alter the authors’ adherence to all the PLOS ONE policies on sharing data and materials. * E-mail: [email protected] habitats are an important component of the process that results in malaria transmission. Mosquito life cycle processes including oviposition, larval development, pupation and emergence occur in aquatic habitats. These habitats are crucial in determining the types of.Iological Characteristics in Habitats of High and Low Presence of Anopheline Larvae in Western Kenya HighlandsBryson A. Ndenga1,2*, Jemimah A. Simbauni1, Jenard P. Mbugi1, Andrew K. Githeko1 Department of Zoological Sciences, Kenyatta University, Nairobi, Kenya, 2 Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, KenyaAbstractBackground: Characteristics of aquatic habitats determine whether mosquitoes will oviposit, hatch, develop, pupate and successfully emerge into adults or not, thus influencing which mosquito species will occupy a habitat. This study determined whether physiochemical and biological characteristics differ between habitats with high and low presence of anopheline larvae. Methods: Physical, chemical and biological characteristics were evaluated in selected habitats twice per month within three highland valleys in western Kenya. Aquatic macro-organisms were sampled using a sweep-net. Colorimetric methods were used to determine levels of iron, phosphate, nitrate, ammonium and nitrite in water samples. Generalized Estimating Equations (GEE) was used to compare parameters between the two categories of anopheline presence. Results: Habitats with high anopheline presence had greater abundance of mosquito aquatic stages and tadpoles and two times more levels of nitrate in water, whereas habitats with low anopheline presence had wider biofilm cover and higher levels of iron in water. Conclusion: Habitats of high and low presence of anopheline larvae, which differed in a number of physical, chemical and biological characteristics, were identified in valleys within western Kenya highlands. Differences in habitat characteristics are critical in determining the number of anopheline larvae that will fully develop and emerge into adults.Citation: Ndenga BA, Simbauni JA, Mbugi JP, Githeko AK (2012) Physical, Chemical and Biological Characteristics in Habitats of High and Low Presence of Anopheline Larvae in Western Kenya Highlands. PLoS ONE 7(10): e47975. doi:10.1371/journal.pone.0047975 Editor: Olle Terenius, Swedish University of Agricultural Sciences, Sweden Received May 28, 2012; Accepted September 19, 2012; Published October 23, 2012 Copyright: ?2012 Ndenga et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This work was funded by the World Health Organization (WHO) Special Programme for Research and Training in Tropical Diseases (TDR)-Research Training Grant (RTG) and Valent BioSciences Corporation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: This research study received part of its funding from a commercial source “Valent BioSciences Corporation”. The authors declare that they have no competing interest relating to employment, consultancy, patents, and products in development or on the market. This does not alter the authors’ adherence to all the PLOS ONE policies on sharing data and materials. * E-mail: [email protected] habitats are an important component of the process that results in malaria transmission. Mosquito life cycle processes including oviposition, larval development, pupation and emergence occur in aquatic habitats. These habitats are crucial in determining the types of.