Ecological Impact of the Invasive Armored Catfish (Loricariidae) on Fish Assemblages and Implications for Conservation in Northern Guatemala

Abstract

Pterygoplichthys in LPR relative to SPR. In LPR, native fishes rely more on watercolumn resources compared to SPR where benthic resources are more important for fish body mass. The relative biomass of the invader was significantly associated with native fish δ13C, along with conductivity and water flow velocity, and water depth and sedimentation had a significant association with native fish δ15N. I conclude that Pterygoplichthys invasion has impacted the trophic ecology and populations of native fishes that share similar food resources. Given the apparent influence of environmental factors on local fish assemblages, additional impacts to aquatic ecosystems must be considered when addressing native fish conservation. Long-term field research and mesocosm experiments could help to elucidate specific mechanisms involved in Pterygoplichthys impact on native fishes and river ecosystems.