| Title | Influence of estuarine plumes on surf zone larval fishes |
|---|---|
| Authors |
Nhleko, Jabulile |
| Publisher | Department of Forestry, Fisheries and the Environment (2026) |
| Contributors |
Contact Person: Nhleko, Jabulile |
| Abstract | This dataset comprises larval fish assemblage data collected from the surf zone adjacent to the Great Kei Estuary and neighbouring estuaries on the South African southeast coast. The study investigated the influence of estuarine plumes on larval fish abundance, composition and diversity under different river-flow conditions. The dataset includes larval fish species composition, abundance and catch per unit effort, together with environmental variables including temperature, salinity, turbidity and dissolved oxygen. The data contribute to understanding the role of estuarine plumes in structuring larval fish assemblages in adjacent surf zones and the influence of variation in river flow on coastal nursery habitats. |
| Methods |
Four sampling sites were sampled seasonally during spring tides over a period of 2.5 years to capture variability associated with rainfall-driven freshwater inflow. Two sites adjacent to the Great Kei Estuary were classified as plume-influenced, while two sites adjacent to the Qolora and Morgan estuaries were classified as non-plume sites, with no direct influence from the Great Kei Estuary plume. All sites were sampled on the same day, with sampling conducted between two hours before and after spring low tide. Larval fish were collected using a small beach seine net measuring 1.5m high and 4.5m wide, with a 0.5mm bar-mesh aperture. The net was walked parallel to the shore for 25m in water depths of less than 1.5m, with three replicate hauls conducted at each site. The net was specifically designed to sample larval fish and consisted of a beach seine fitted with a central tapering cone, similar to a WP2 plankton net, with a 0.57m mouth diameter and a tied cod end. Larvae concentrated at the tapered end of the net, and individuals adhering to the sides of the seine or cone were washed into the cod end. Samples were subsequently preserved in 10% formaldehyde in seawater. Sampling sites: Left of Kei Mouth (-32.6772120315581 S; 28.3888970129191 E); right of Kei Mouth (-32.68158001 S; 28.38359999 E); Seagulls (-32.63415797 S; 28.43062598 E); Morgan Bay (-32.709335 S; 28.345017 E). |
| Taxonomic information |
General Taxonomic Coverage:
Taxonomic Classification |
| Data | |
| Temporal extent | 01 Jun 2018 – 26 Feb 2016 |
| Geographic extent |
Amathole Marine Protected Area (MPA), Eastern Cape, South Africa
North: -32.602569 |
| Keywords | African Coelacanth Ecosystem Programme (ACEP) , completed , Embargoed , EPSG 2048 , FISH , Fish abundance and distribution , grid , INDIAN OCEAN , Mean Sea Level , meter , OCEANS , Species abundances |