The resilience of animal behaviour to disturbance

The concept of resilience is now widely used to understand the vulnerability of complex systems to disturbances. It is emerging that more diverse systems are more resilient to disturbances. Here we develop a conceptual understanding of the resilience of behavioral systems and assess how this measure is related to the diversity of behavioral sequences modeled using Markov chains. We show that the resilience of behavior is related to its unpredictability, a diversity measure, using simulations and empirical data collected at ten study sites over 30 years. The more predictable behavior is, the less resilient it becomes. Such influences on behavioral resilience cannot be related to the effect size of disturbances in inter-population comparisons. However, we show that such measures are meaningfully related to the influence of disturbances when comparing the same population exposed to different ecological conditions. We show that behavior predictability can be driven by ecological conditions. For example, an increase in food availability can increase the duration of foraging bouts, hence constraining the dynamics of the population’s behavior. Such constraints increase behavioral predictability and in turn weaken its resilience to disturbance. This empirically-driven theoretical study offers a framework to manage exposure of animal populations to disturbance

Crescimento e desenvolvimento de boto-cinza (Sotalia guianensis) do litoral do Espírito Santo

Estudou-se o desenvolvimento do boto-cinza (Sotalia guianensis) do litoral do Espírito Santo e verificou-se se a análise das radiografias da aleta peitoral pode ser utilizada para tal. Trinta e sete botos passaram pela determinação do comprimento total (CT), análise do grau de fusionamento das vértebras e radiografia das aletas peitorais. O CT ao nascimento foi de 103,3cm e o de animais maduros fisicamente 187,5cm. Observou-se correlação entre o CT, as epífises distais do rádio e da ulna e correlação entre o grau de fusionamento vertebral e a epífise distal do rádio. Concluiu-se que a análise radiográfica das aletas peitorais é uma boa maneira de avaliar o grau de maturação física do boto