The Colias genus in the collections of the Natural History Museum of Sibiu, Romania

摘要

Superabundance of seabirds have witnessed a rapid increase in their home range, occupying most islands worldwide and disturbing the sensitive local biodiversity. While superabundant seabirds have the potential to drastically change the physicochemical properties of the habitat through an excess deposition of excrements the potential consequences of these alterations on plant physiology has received little attention. Here we aim to evaluate the effects of the guano deposition of the yellow-legged gull Larus michahellis on the leaf physiology of six species of plants Urtica urens, Malva arborea, Malva multiflora, Pallenis maritima, Coelostephus myconis , and Limbarda crithmoides found during the breeding season of the bird in six Mediterranean islands in central North Algeria. The different islands had different population sizes of the yellow-legged gull Larus michahellis . We specifically collected fresh leaves that were stained or not by guano to estimate the stomatal density, water content, chlorophylls A-B, and carotenoids. The results showed that there was interspecific variability in the response of the guano stain on the four physiological parameters. Overall, there was a negative linear correlation between all parameters and the percentage cover of the leaf by the guano in all plant species. These results suggest that superabundant seabirds might induce physiological changes in plants that might lower their fitness and affect the insular ecosystem.