Temperature effects on parental care behaviour in native and invasive Palaemon shrimp species

Environmental changes and the spread of non-native species significantly affect wetland ecosystems, such as coastal lagoons. This study investigates the effects of increased temperature on parental care behaviour, specifically pleopod fanning, in ovigerous females of the following three Palaemon species: the global invader Palaemon macrodactylus and the Mediterranean native Palaemon elegans and Palaemon adspersus. Under controlled laboratory conditions, we measured pleopod beats per minute across a temperature gradient to assess species-specific responses. Our results showed significant inter-species differences in fanning behaviour, with P. elegans exhibiting the lowest pleopod beat rate overall. Temperature showed a strong positive correlation with pleopod beats across all species, whereas dissolved oxygen negatively correlated with pleopod beats in P. adspersus and P. macrodactylus. Interestingly, P. elegans exhibited a unique response compared with its congeneric species, because it was the only species among those studied that did not show a negative correlation between pleopod beat rate and dissolved oxygen concentration. These findings have enhanced our understanding of the behavioural responses of native and invasive Palaemon species to environmental alterations, providing valuable insights into how species interact with their changing environments.