Where to fish in the forest? Tree characteristics and contiguous seagrass features predict mangrove forest quality for fishes and crustaceans (Dataset)

Wanjiru, Caroline; Nagelkerken, Ivan; Rueckert, Sonja; Harcourt, William; Huxham, Mark

Abstract

1) Mangroves often support rich fish and crustacean communities, although faunal abundance and diversity show strong spatio-temporal variability. Consistent patterns in mangrove animal communities might be dictated by forest characteristics, by seascape context, or by some combination of these factors. Predicting drivers of spatial heterogeneity in mangrove faunal communities can better support the zoning of forests for management purposes, for example by identifying sites important for fisheries nursery provision.
2) We sampled 14 sites within a large (4000 ha) mangrove forest in Kenya, quarterly over a period of two years. There were clear and consistent differences in the quality of sites for fish and crustacean abundance and diversity.
3) Forest characteristics (as summarised by the complexity index, CI) and seascape metrics (the presence, area and configuration of contiguous seagrass) were strong predictors of site differences. However, they showed opposite influences on dominant members of the fish and crustacean faunas, with CI correlated negatively with fishes and positively with crustaceans, and seagrass area correlated positively with fishes and negatively with crustaceans.
4) Synthesis and applications. Sites within the same mangrove forest exhibit consistent differences in fish and crustacean abundance. However, the fish and crustacean communities (and particularly dominant species within them) act differently in response to forest and seascape characteristics. Old growth, mature forest, set in a seascape of seagrass patches with bare sediment, was associated with highest crustacean abundance. In contrast, denser smaller trees and seascapes with larger, continuous areas of seagrass correlated better with fish abundance. Zoning for management, as mandated in new Kenyan policy, will need to consider these differences in seascape use between fish and crustaceans.

Citation

Wanjiru, C., Nagelkerken, I., Rueckert, S., Harcourt, W., & Huxham, M. (2023). Where to fish in the forest? Tree characteristics and contiguous seagrass features predict mangrove forest quality for fishes and crustaceans (Dataset). [Dataset]. https://doi.org/10.17869/enu.2023.3069847

• Online Publication Date: Apr 14, 2023
• Publication Date: Apr 14, 2023
• Deposit Date: Apr 13, 2023
• Publicly Available Date: Apr 14, 2023
• Publisher: Edinburgh Napier University
• DOI: https://doi.org/10.17869/enu.2023.3069847
• Keywords: Nursery habitat, ecosystem services, shrimp, juveniles, mosaic, East Africa, complexity
• Type of Data: fish and crustacean abundance, habitat characteristics
• Collection Method: Fyke nets deployed in 14 mangrove creeks, mangrove forest surveys, satellite imagery analysed for seagrass presence and abundance.