Vital Rates

All the pressures studied in this project can potentially induce behavioural and physiological changes in the animals that would be reflected by changes in their vital rates.

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Survival and Reproductive rates

The potential stressors studied in this project will be used as covariates in mark-recapture models to explore their long-term effects on adult, juvenile and calf survival, recruitment and/or reproduction rates of short-finned pilot whales in Madeira.

A life history of each individual identified can be constructed to run mark-recapture models and test the effects of the stressors on survival and recruitment rates. From the individual movement analyses, the spatial exposure of each identified individual to variables (maritime traffic, WW, ambient noise and marine litter) can be grouped by individuals observed inside high stressor areas or not. The annual number of whale watching boats and density of marine litter can be tested as time dependent variables on the demographic parameters. Individual variables obtained from biopsy samples, i.e., PCBs and cortisol levels, can only be tested on the sampled individuals. Therefore, their effect can only be tested on past reproductive rates and not yet on survival or recruitment rates.

The effect of each stressor will be tested individually then together as cumulative effects. Each model will be ranked to understand which stressors are more important for the survival, recruitment and reproduction rates.