Trophic transfer of Everglades marsh consumer biomass to Everglades Estuaries (FCE), Everglades National Park, South Florida from December 2010 to Present

We measured the trophic transfer of secondary consumer biomass from the Everglades marshes to the oligohaline reaches of the Shark River by sampling the diets of four common large bodied piscivorous fishes occurring at the marsh-estuary oligohaline ecotone. The four species sampled were Florida bass (Micropterus floridanus), bowfin (Amia calva), common snook (Centropomus undecimalis), and red drum (Sciaenops ocellatus). We sampled diets via pulsed gastric lavage, a relatively non-lethal and effective sampling technique used to measure trophic interactions. We quantified trophic transfer of marsh biomass to the estuary when a focal piscivore consumed a prey species that was likely a migrant from adjacent marshes. A more detailed description of these methods can be found in citation #28. In the presented data, we combined estimates of relative abundance of piscivores from standardized electrofishing techniques (# of piscivores/ 100 meters of sampled shoreline) with biomass of marsh species consumed in the estuary to calculate the biomass (g) transferred to the estuary per 100 meters of shoreline. These values serve as our index of how much biomass is being exported off of the marsh to the estuary through consumer mediated habitat linkages. An important key finding from this work is that disturbance, in particular drought, can sever this biomass linkage, and conserve biomass export off of karstic wetlands to estuaries through of marsh secondary consumer trophic pathways.本研究通过对栖息于沼泽-河口低盐生态交错带（marsh-estuary oligohaline ecotone）的4种常见大型肉食性鱼类（piscivorous fishes）的食性开展采样，测定了大沼泽地（Everglades）次级消费者生物量（secondary consumer biomass）向鲨河（Shark River）低盐河段（oligohaline reaches）的营养传递（trophic transfer）过程。 本次采样涵盖的4个物种分别为佛罗里达黑鲈（Micropterus floridanus）、弓鳍鱼（Amia calva）、普通锯盖鱼（Centropomus undecimalis）及眼斑拟石首鱼（Sciaenops ocellatus，俗称红鼓鱼）。 我们采用脉冲式胃灌洗法（pulsed gastric lavage）进行食性采样，该方法相对非致死且高效，可用于量化营养相互作用。 当目标肉食性鱼类摄食了大概率来自邻近沼泽的洄游猎物时，我们即可完成沼泽生物量向河口的营养传递量化。 有关本研究方法的详细描述可参见参考文献#28。 在本研究提供的数据集中，我们将标准化电捕鱼法（standardized electrofishing techniques）测得的肉食性鱼类相对丰度（采样每100米岸线的肉食性鱼类数量）与河口内被摄食的沼泽物种种群生物量相结合，计算得到每100米岸线向河口转移的生物量（单位：克）。该数值可作为衡量通过消费者介导的生境连接，从沼泽向河口输出的生物量规模的指标。 本研究的一项重要核心发现为：干扰（尤以干旱为代表）可切断该生物量连接，并通过沼泽次级消费者营养通路保护喀斯特湿地（karstic wetlands）向河口的生物量输出。