Original paper
Selection of food items by the omnivorous freshwater crustacean Aegla longirostri (Decapoda, Aeglidae)
Cogo, Gláucia Bolzan; Biasi, Cristiane; Santos, Sandro
Fundamental and Applied Limnology Volume 192 Nr. 1 (2018), p. 43 - 51
published: Nov 16, 2018
published online: Sep 3, 2018
manuscript accepted: Aug 19, 2018
manuscript revision received: Aug 17, 2018
manuscript revision requested: Jun 14, 2018
manuscript received: Apr 27, 2018
ArtNo. ESP141019201003, Price: 29.00 €
Abstract
The fragmentation of leaves during the leaf decomposition process is done mainly by immature insects, but there are other important organisms, such as omnivorous macroconsumers. Leaves are broadly available as a food source in streams, but they are also highly variable in their structure and chemical composition, and consumers respond to these differences by displaying preference types of leaf litter. Studies investigating the feeding preference among different plant items are common, but those that investigate omnivorous macroconsumers and also include animal items are scarce. Because of this, we analyzed the feeding preference of Aegla longirostri, an omnivorous macroconsumer, through standardized experiments offering different plant and animal food items. We performed three experiments where we offered leaves conditioned on the stream, unconditioned leaves and fish fillet as food items. For the aeglids, microbial conditioning was more important than the leaves’ initial chemical quality. Conditioned leaves showed higher nutritional quality and lower hardness than unconditioned leaves, being preferred by the aeglids. Besides this, the consumption of animal tissue was higher than that of plant matter. Aeglids prefer to consume animal tissue, followed by conditioned leaves, with unconditioned leaves being the least preferred resource, showing that aeglids prefer food items according to their nutritional value.
Keywords
Aeglids • headwaters • macroconsumers • shredders • streams