| Macroinvertebrate detritivores (consumers) can assist in the transfer of energy into and amongst aquatic ecosystems. Consumers can create coarse and fine-particulate organic matter in the process of feeding, and consumers can also aid in the transfer of energy by serving as a food source for other stream organisms. In these ways consumers can be important to the transfer of energy through aquatic ecosystems. Through investigating the relationship between consumers and resources I may get a better understanding of how resources affect consumer behavior, and the role consumer taxa play in resource loss. My goal was to understand how individual macroinvertebrate consumers and consumer communities respond to changes in resource quality, and how riverine network location, in conjunction with resource quality, influences consumer resource use. I found that consumers responded positively to resource quality. When consumers in the lab were offered a high quality resource feeding activity increased, relative to a low quality resource. In stream networks consumer communities were richer and more abundant in the presence of a high quality resource. Additionally, I found that the consumer-resource relationship changed at different location in the riverine network. In headwaters consumer communities were rich and abundant, and as consumer abundance in litter bags increased, resource loss increased. Consumer communities in mainstem locations were less abundant than in headwaters. When consumer abundance in mainstem litter bags increased, resource loss either did not change with abundance or resource loss decreased. Suggesting that the consumer-resource relationship may vary between headwaters and mainstems. |
