Laboratory of Aquatic Zoology, Division of Research and Postgraduate Studies, National Autonomous University of Mexico, Campus Iztacala Av. de Los Barrios No.1, C.P. 54090, Los Reyes, Tlalnepantla, State of Mexico, Mexico.
* Correspondence author: E. Mail: ssssarma@gmail.com.
Aquatic vertebrate predators (fish and amphibians) influence the diversity and abundances of their prey such as zooplankton. However, predators also indirectly affect the prey populations by releasing chemical cues into the medium. Most studies have focused on the indirect effects of fish but very few on amphibians. In this work, the allelopathic effects of conditioned-medium from fish (Ameca spendens), larval axolotl (Ambystoma mexicanum), and frog tadpoles (Hyla plicata) on the population growth of the common rotifer Plationus patulus were evaluated. Compared to controls (free from allelochemicals), P. patulus grown in the presence of vertebrateconditioned-medium had higher peak population abundances. Within the vertebrate predators, the conditioned medium from axolotl and tadpole resulted in a 10-day longer phase of P. patulus. In controls and in fish-conditioned medium, there was no lag phase. The rate of population growth of P. patulus varied from 0.09 to 0.17 per day, depending on the treatment; the lowest being in fish-conditioned medium. These results have been interpreted in relation to the predator species.
Allelochemical, amphibian, fish (Ameca spendens), frog tadpole (Hyla plicata), larval axolotl (Ambystoma mexicanum), population dynamics, rotifer, zooplankton
