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The study considered two ecologically similar coastal areas in Tuscany (Italy). One site belongs to a protected natural area and the other one is in front of a camping site. We analysed the impact of human activities, such as trampling and mechanical beach cleaning, on Talitrus saltator. It turned out that the population density was affected in that it first disappeared from the area at the camping site, then recolonised it once the peak of the tourist season at the camping site had passed. The results confirm the sensitivity of this species and its plasticity in adapting to different conditions on the one hand, and the positive effects of diversification in resource management on the other hand.
This study focused on verifying the fluctuating asymmetry hypothesis in the crustacean Talitrus saltator, which lives in sandy beaches. We analysed three populations, one from an unpolluted Tuscan beach relatively free of tourism, and two from Sicilian beaches, which have been increasingly used for tourism and have been exposed to hydrocarbon/pesticide pollution. Results confirmed the sexual dimorphism in the second antennae flagella, which in the Tuscan population presented directional asymmetry. This population had a significant level of fluctuating asymmetry in the P6 and P3 meri. The results showed the importance of the developmental stage during which environmental mechanical stresses act.
This paper evaluates the second part of a three-year field study to investigate the effects of the beach macro- and meiofauna community structure on the decay of stranded wrack on Hel Beach (see Jędrzejczak 2002),f ocusing on successional changes and the colonisation of wrack by beach fauna. The investigation enabled the associated faunal assemblages to be characterised. Zostera marina tissue was colonised by the supralittoral fauna in two distinct phases. The macrofauna, including the talitrid amphipod Talitrus saltator,ad ult Diptera and Coleoptera, colonised the wrack within a day,with maximum numbers being recorded after 3 days. Thereafter,their numbers in the samples declined and the meiofauna, consisting of nematodes, oligochaetes,tur bellarians and dipteran larvae, became increasingly abundant. After 18 days,the wrack surface was dominated by meiofauna. This faunal succession was not directly related to the degradation of the seagrass tissue,whic h proceeded linearly throughout the study period. Exclusion of macrofauna from the wrack by the use of < 1 mm mesh litterbags had no appreciable effect on the rate of dry matter loss. Therefore,the major macrofaunal wrack consumers,including T. saltator and Coleoptera,d id not affect the rate of seagrass disintegration. The effect of meiofaunal nematodes, oligochaetes,gast rotrichs and turbellarians on wrack breakdown could not be accurately determined. However,the development of the meiofaunal community suggested that changes in the fauna community were linked more closely to successional changes in the chemistry and/or microflora of the beach wrack than to its physical breakdown.
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