Name: Francyne Lyrio Mischiatti
Type: MSc dissertation
Publication date: 20/02/2018
Advisor:
Name | Role |
---|---|
Albert David Ditchfield | Advisor * |
Examining board:
Name | Role |
---|---|
Albert David Ditchfield | Advisor * |
ANA CAROLINA SRBEK DE ARAUJO | External Examiner * |
Roberta Paresque | Internal Alternate * |
Sérgio Lucena Mendes | Internal Examiner * |
Summary: Abstract
The use of ultrasonic detectors are useful in complementing information on the behavior and ecology of bats traditionally studied through mist nets or traps. Through the analysis of acoustic parameters of the echolocation calls it is possible to identify species, genera or family to a greater or less degree of certainty, indicating that a sound bank can be an important tool for the study of these species. However, species identification is only possible when the characteristics of the echolocation sounds of the species present in the studied area was been previously described. Individuals in the Molossidae family are open space foragers, which emit long narrow band pulses and relatively low frequencies. However, several molosídeos studies present a high level of vocal plasticity, adapting their calls of echolocation according to the circumstances. The structure of the calls can change depending on the task that the bat performs (locating, detecting or pursuing prey) and by the level of clutter present in the foraging environment. Thus, the objective of this work was to describe the variation of the parameters of the calls of Molossus, Molossus rufus and Molossus coibensis according to different approaches to the clutter. The three species studied showed vocal plasticity. M.molossus, M. rufus and M. coibensis had a similar sequence structure during the flight path, emitting modulated frequency (MF) calls when they were close to the ground and clutter and quase-constant frequency (QFC) when they were far from the ground and clutter. The greatest variation founded when they passed in intermediate distance to the ground and clutters: M. molossus alternated QFC and MF calls while the other two species exhibited different QFC calls with maximum and minimum frequency higher than the QFC call characteristic of each specie