DOI: 10.5061/dryad.qfttdz0t5
title: Data from: Effects of Nile tilapia (Oreochromis niloticus) cage aquaculture on water quality in the world’s largest tropical lake

description: Cage aquaculture in tropical lakes is an efficient means of generating
 fish protein to ensure food security and support livelihoods. However, it
 has been repeatedly criticized as injurious to lake ecosystems due to
 eutrophication and other problems, and therefore ill-advised. This study
 examined the impacts of Nile tilapia (Oreochromis niloticus) cage farming
 on water quality across spatial scales in the world’s largest tropical
 lake, Lake Victoria. The primary objectives were to determine if water
 quality patterns differed between cage and control stations along a
 background limnological gradient, and to identify the water quality
 variables that contributed most to these differences. We postulated that
 the spatial arrangement of sites in the lake would drive overarching
 patterns of water quality variation, while cage aquaculture would have
 additional impacts on these parameters across the spatial gradient. Water
 column samples were collected from both cage and control stations at four
 locations along a known gradient in limnology, across 2 years. The results
 revealed significant differences in water quality between cage and control
 stations at all four sites, with dissolved oxygen, pH, and silica
 contributing the most to these differences. These findings highlight the
 need for site-specific management strategies to both mitigate the
 environmental impacts of cage aquaculture in tropical lakes and ensure
 continuity of aquaculture production. Our study provides an approach that
 can be applied to tropical lakes and reservoirs around the world.
 Effective nutrient management and continuous monitoring are recommended to
 support sustainable aquaculture in ecosystems under stress from growing
 lakeside populations.
description: # Data from: Effects of Nile tilapia (Oreochromis niloticus) cage
 aquaculture on water quality in the world’s largest tropical lake Dataset
 DOI: [10.5061/dryad.qfttdz0t5](10.5061/dryad.qfttdz0t5) ## Description of
 the data and file structure Data for "Effects of Nile tilapia
 (Oreochromis niloticus) cage aquaculture on water quality in the world’s
 largest tropical lake" (Okechi et al., 2025). The .xlsx file contains
 raw data on water quality parameters collected from the Kenyan waters of
 Lake Victoria in March 2023 and March 2024.  Samples were collected in
 triplicate at 1m depth intervals. ### Files and variables #### File:
 2023\_2024\_water\_quality\_data.xlsx **Description:** Water quality
 parameters ##### Variables * depth_m: Depth (m) * total_depth: The total
 depth of the site, in meters. Empty cells in this column refer to sampling
 periods when this data was not collected (2024). * Secchi (m) * Temp_c:
 Temeprature (Celsius) * TN: Total nitrogen (ug/L) * TP: Total phosphorus
 (ug/L) * NO3: Nitrate (ug/L) * NO2: Nitrite (ug/L) * SRP: Soluble reactive
 phosphorus (ug/L) * SIO2: Silicon dioxide (ug/L) * NH4: Ammonium (ug/L) *
 Chl_a: Chlorophyll-a (mg/L) * ALK: Alkalinity (mg/L) * HARD: Hardness
 (mg/L) * DO: Dissolved oxygen (mg/L) * Cond: Conductivity (uS/cm) * TDS:
 Total dissolved solids (mg/L) * Salinity (ppt) * pH * ORP:
 Oxidation-reduction potential (mV) * Turbidity (FTU) ## Code/software
 There is no software or code needed to view the data.