Mechanisms driving the consumption and transport of tidal marsh nutrients and energy by fishes are of key interest in the San Francisco Estuary, CA, USA. By combining multiple data sources (gill-net catches, gut contents, channel morphology, tides), we modeled spatial and temporal patterns of fish abundance and gut fullness across a tidal marsh elevation gradient. Channel depth, microhabitat, and tide were important predictors of fish abundance and gut fullness. Species, feeding guild, and season were also important to fish abundance but not to gut fullness, suggesting that abundance was more related to physical constraints of shallow water than to prey availability. Multiple feeding guilds overlapped in space and time at interaction hotspots in subtidal channel habitat near the marsh entrance. In contrast, fish use of shallow intertidal marsh channels was more variable and indicated tradeoffs between foraging and predation. Gut content analysis revealed moderate-to-high gut fullness for all feeding guilds and models predicted high gut fullness in subtidal reaches during tidal flooding, after which fish fed intensively throughout the marsh. While mysids, amphipods, and detritus were common prey among feeding guilds, variation in prey consumption was apparent. Overall, complex tidal marsh hydrogeomorphology driving land-water exchange and residence time may diversify and enhance benthic and pelagic food web pathways to fishes and invertebrates. Furthermore, these findings substantiate the notion that dynamic tidal marshes in this system can support robust secondary production, foraging by multiple feeding guilds, and trophic transfer by fishes to the estuarine mosaic.

推动鱼类消耗和运输潮汐沼泽养分和能量的机制是美国加利福尼亚州旧金山河口的主要兴趣点。通过结合多个数据源（刺网捕获量、肠道内容物、通道形态、潮汐），我们模拟了潮汐沼泽海拔梯度上鱼类丰度和肠道丰满度的空间和时间模式。通道深度、微生境和潮汐是鱼类丰度和肠道丰满度的重要预测因子。物种、饲养行会和季节对鱼类丰度也很重要，但对肠道丰满度并不重要，这表明丰度更多地与浅水的物理限制有关，而不是与猎物的可用性有关。在沼泽入口附近的潮下带栖息地的相互作用热点处，多个饲养行会在空间和时间上重叠。相比之下，鱼类对浅潮间带沼泽通道的利用变化更大，表明在觅食和捕食之间进行权衡。肠道内容分析显示，所有饲养公会的肠道丰满度为中到高，模型预测潮汐洪水期间潮下带的肠道丰满度较高，之后鱼在整个沼泽地集中喂养。虽然糠虾、片脚类动物和碎屑是饲养行会中常见的猎物，但猎物消耗的变化很明显。总体而言，复杂的潮汐沼泽水文地貌驱动陆水交换和停留时间可能使鱼类和无脊椎动物的底栖和远洋食物网途径多样化并增强。此外，这些发现证实了这一观点，即该系统中的动态潮汐沼泽可以支持强大的二次生产，由多个饲养行会觅食，