Effect of the filling season on aquatic plants in Mediterranean temporary ponds

Aims Pond environmental conditions may differ among years with regards to the season in which ponds begin to fill.We experimen-tally evaluated how seedling emergence,plant growth and phe-nology differed among years in which filling occurred in winter,autumn or spring.Methods We collected sediments from a natural temporary pond and located them in aquariums.They were placed in a climatic chamber that simulated annual variation in field environmental temperatures and light conditions.Aquariums were assigned to one of three treat-ments,which differed in the date on which they were filled with water(autumn,winter and spring).We counted the number of seed-lings of different species emerged and recorded data about the pres-ence of flowers,seeds or spores every week.The experiment was finished in June,when we harvested the plants and estimated their biomass.Important Findings In most species,seedling emergences were primarily related to time after filling,and thus synchronized their life cycles with the unpre-dictably timed wet phase of the ponds.Autumn filling resulted in the highest numbers of seeds/spores.However,winter filling pro-moted plant growth the most.In the spring filling treatment,more terrestrial plant seedlings emerged and fewer seeds/spores were produced.When ponds are flooded earlier,plants may produce a higher number of propagules.However,in years when inundation is delayed to spring and hydroperiods are short,seedling emergence deplete the seed bank and there is little to no seed production,while terrestrial monocots are able to colonize pond basin.

Feather content of porphyrins in Eurasian eagle owl(Bubo bubo)fledglings depends on body condition and breeding site quality

Porphyrins are pigments produced in most animal cells during the synthesis of heme,but their importance for external coloration is unclear.Owls(Order Strigiformes)are among the few animals that accumulate porphyrins in the integument,where it could serve as a means of signaling.Here we hypothesized that the porphyrin content of feathers may depend on body condition and breeding site quality in Eurasian eagle owl(Bubo bubo)fledglings and,thus,constitute amplifiers of the quality of the area where they are born.Using high-performance liquid chromatography,we found 2 porphyrins(protoporphyrin IX and coproporphyrin III)in the body feathers of 19 eagle owl fledglings from 7 breeding territories.Coproporphyrin III,but not protoporphyrin IX feather concentration,was positively associated with the body mass of fledglings and with the quality of the breeding sites where they were reared with respect to food quality and availability.As coproporphyrin III is produced under oxidative stress,we suggest that good breeding sites may lead to fledglings in good condition.This,in turn,may make fledglings induce a certain level of free radical and coproporphyrin III production to signal to conspecifics their site-mediated capacity to cope with oxidative stress.This is the first time that porphyrin content in the integument has been found to be related to individual quality,opening a new scenario for studying evolution of animal coloration.