Diel vertical migration of copepods and its environmental drivers in subtropical Bahamian blue holes

• DOI: 10.1007/s10452-020-09807-4
• Publication Date: 2020-11-02T02:02:20Z
• Authors: Yongcui Sha; Huan Zhang; Marcus Lee; Caroline Björnerås; Martin Škerlep; Raphael Gollnisch; Simon David Herzog; Gustaf Ekelund Ugge; Jerker Vinterstare; Nan Hu; Varpu Pärssinen; Kaj Hulthén; P. Anders Nilsson; Karin Rengefors; Christer Brönmark; R. Brian Langerhans; Lars-Anders Hansson
• Keywords: Diel vertical migration; Seasonality

Abstract Diel vertical migration (DVM) is the most common behavioral phenomenon in zooplankton, and numerous studies have evaluated DVM under strong seasonality at higher latitudes. Yet, our understanding of environmental drivers low latitudes, where seasonal variation less pronounced, remains limited. Therefore, we here examined patterns distribution copepods six subtropical Bahamian blue holes with different food web structure tested role several key variables potentially affecting this behavior. Day night samplings showed that generally performed DVM, characterized by downward to deeper depths during day upward surface waters night. Across all holes, daytime depth calanoid correlated positively both predation risk resources (Chlorophyll a ), but was affected ultraviolet radiation (UVR). A potential explanation since UVR continuous threat across seasons, zooplankton established photoprotective pigmentation making them vulnerable threat. The also size-structured segregation, larger individuals were found day, which further strengthens suggestion major driver these systems. Hence, contrast show despite constant exposure UVR, predator avoidance availability are pronounced copepod those suggesting main may vary among systems, systematically latitude.