Lucia Fanini

Variation of genetic and behavioural traits in the sandhopper Talitrus saltator (Crustacea Amphipoda) along a dynamic sand beach

In an attempt to unravel the possible relationships among coastal stability, genetic variability and orientation behaviour in the sandhopper Talitrus saltator, we have screened four subpopulations of this species. Sandhoppers along 3 km of a dynamic sand beach were studied for orientation performance (i.e. adherence to the seaward theoretical escape direction (TED)) and sequence variation for a fragment of the mitochondrial (mt) gene encoding for the cytochrome oxidase subunit I (COI). The sampling sites differed in the stability of the shoreline (from severely eroded to accreting). Analysis of molecular variance (AMOVA) revealed significant subdivisions among the four locations. The subpopulation sampled at the most eroded point showed no haplotype diversity and had the highest scatter in orientation. Genetic diversity increased with decreasing erosion. Orientation performances were best where the beach is in dynamic equilibrium, and were progressively more scattered at the accreting points. Multiple linear regression analyses demonstrated that the variables and factors that affected orientation significantly were daytime, global solar radiation, sex of individuals and haplotype diversity. Environmental factors are likely to influence sandhopper behaviour on a short and medium time scale (i.e. from single individual life span to a few generations). The data also suggest that temporal stability of the shoreline has a positive effect on the genetic variability of the resident sandhopper populations.

Behavioural adaptation to different salinities in the sandhopper Talitrus saltator (Crustacea: Amphipoda): Mediterranean vs Baltic populations

The sandhopper Talitrus saltator is common on sandy beaches at different latitudes. Therefore, behavioural variations allowing them to cope with a wide range of environmental variation are expected. To test the hypothesis that behavioural adaptations to natural environments are characterised by different salinities, we compared two behaviours (substrate choice and escape from immersion) of two T. saltator populations from a Mediterranean (high salinity) and a Baltic Sea (low salinity) sandy beach. T. saltator preferred to burrow in the high salinity substrate, irrespective of its beach of origin. Regarding orientation to escape from immersion, Baltic sandhoppers always oriented landwards, whereas Mediterranean sandhoppers showed a significant orientation landwards only when immersed in high salinity sea water. These behavioural traits matched the different environments, and this adaptation capability can be used as a model to analyse the response of a keystone species to environmental changes.

Orientation of littoral amphipods in two sandy beaches of Brittany (France) with wide tidal excursions

Sandhoppers orient towards the shoreline using a sun compass when they are subject to dry conditions. In this study we analysed the orientation of populations from two sandy beaches with wide tidal excursions (Brittany, France): at Damgan (sea to the South) and at Le Verger (sea to the North). At Le Verger beach Talitrus saltator was found together with Deshayesorchestia deshayesii (former Talorchestia deshayesii). The results of the experiments on sun and landscape orientation showed that the Damgan T. saltator oriented better with ebbing tides than with rising tides, while the Le Verger T. saltator showed the opposite trend as a response to tides. This is probably related to the differing risk of being swept away by tides at the two localities. D. deshayesii was found to be more scattered in orientation than T. saltator, probably because it is a recent colonizer of that beach.

Deconstructing responses of sandy beach arthropodofauna to shoreline erosion: looking for the proper spatial scale to monitor biodiversity

The suitability of the small spatial scale of sandy beaches was tested as unit for monitoring biodiversity. The study targeted a coastal stretch in central Mediterranean, characterised by a patchy landscape and erosion trend. Beach arthropod communities (abundance, biodiversity and behavioural adaptation) were considered in the context of ongoing changes and threats to beach habitats. Nine beach units were selected as part of three main coast sectors, each with a different exposure. Beach units were sampled for arthropod diversity, which was assessed at different levels of organisation: taxa abundance, diversity indices and behavioural adaptation. These features were used as response variables in models considering beach physical factors. Sand grain size, swash extent and beach slope resulted the driving forces for abundance and diversity. Behavioural tests indicated a local adaptation to the shoreline direction, with mean angles of orientation seawards. Data related to biodiversity assessment were applied to the estimate of Conservation and Recreation Indices (CI and RI). Coast sectors subject to different erosion rates scored differently, pointing to a potential conflict in management of beaches subject to physical erosion. Overall, data depicted beach sectors, each one including one or more beach units, as the most suitable dimension for deconstruction to the small-spatial scale. The selection of the scale for deconstruction, applicable to geomorphological, biological and managerial contexts, would be of paramount importance to guide decision-making and compare coastal stretches also in other geographic contexts.

Monitoring changes in sandy beaches in temperate areas through sandhoppers' adaptations

Sandhoppers (Amphipoda, Talitridae) are keystone species of sandy beach ecosystems in temperate areas. Several traits have been studied and proposed as bioindicators of impacts on sandy beaches, at individual (physiology and behaviour), population (life cycle, abundance, population dynamics and structure, morphometry and fluctuating asymmetry) and species (genetic structure and variation) levels. Sandy beaches, where these species spend their whole life cycle, are dynamic environments, subject to periodic changes (night-day, tides and seasons), as well as to impacts that may cause erosion or accretion of the littoral zone. The first response of an animal to potentially injuring factors is shown by its avoidance behaviour regarding the potential stress. This behaviour may be a rapid escape reaction, shown by single individuals, the whole or part of the population. Activity rhythms, changes in zonation, burrowing, escape reactions, orientation towards the optimal zone on the beach, are all adaptations to environmental changes, increasing the survival chances of the individuals and populations that express such behaviours. In this paper we present case studies of the talitrid species’ behavioural adaptations related to natural and human impacts on sandy beaches in the Mediterranean: (1) erosion/accretion dynamics of a Tyrrhenian beach in central Italy (Maremma Regional Park), and (2) increasing urbanisation on a beach in north-western Morocco (Oued Laou river mouth). The best behavioural adaptation was shown by the populations from more stable coastlines. For the survival value of rapid and possibly anticipatory responses to stressful factors, behavioural variation may be proposed as an early-warning indicator of environmental changes. The adaptation at higher levels (population and species) may reflect, on the one hand, the evolvability of the species and, on the other hand, the changeability of the environment. Adaptations at population level may be used as bioindicators of past changes over generations and evolutionary times.

Interdisciplinary environmental studies: A primer. By Gunilla Öberg

The word ‘interdisciplinary’ is broadly used (around 32,800,000 results when typing the word in web search engines), and often associated to a number of different meanings, but sometimes also to no meaning at all. Besides, the word is too often associated with research papers and projects with unclear research hypotheses or weak data. Most of us have encountered the ‘interdisciplinary’ adjective applied to a confused issue, in which case it is more likely to increase the confusion rather than to resolve it. As a consequence, the first reaction to the occurrence of the word ‘interdisciplinary’ is often sceptical, when not openly adverse. This book accepts from the very beginning, i.e. the title, the challenge of overcoming this language misuse and its main malicious effect, that is the gradual loss of the meaning of the word itself (see CAROFIGLIO 2010 for an anthology on the use of some relevant words of everyday language). Lexical issues aside, the strengths of this approach are widely recognised, as demonstrated by the growing number of calls for projects and papers explicitly asking for interdisciplinary work. Such growing requests however encourage the cursory rough use and interpretation of the concept, with no time left to establish or update proper theoretical background and/or methodology. Environmental studies are not exempted by such ongoing dynamics in demand and offer of interdisciplinary studies. The overall goal of the book is therefore to break the loop established by the increasingly superficial use of the word ‘interdisciplinary’ across research projects and papers in ecology, by providing theoretical and practical inputs. A strong theoretical background and the sound measures supplied throughout the text effectively counter our perception of the interdisciplinary’ word as a fancy but meaningless adjective, used to attract audience or justify confused background. The notion is explicitly addressed in a paragraph within Chapter 7, aptly named ‘Confusing interdisciplinary with ‘everything’’. The practical inputs to this book are examples of real cases discussed under different lights in relation to each issue raised. The goal is to increase clarity by analysing the path leading to the implementation of an interdisciplinary study in Ecology, from the very beginning until its defence in peer review. The examples from Chapters 4 and 5 deal with real cases but leave the impression of a perception bias, since limited to collaborators of the author, and therefore too linked to the author’s environment. At this point, readers have the feeling that many issues, depending on the different background of the researchers, are still to be uncovered and discussed. Although the examples referred to are well-planned studies, thus likely to supply results valid at a broad scale (some examples: ‘Adapting conservation policy to the impacts of climate change’, ‘Multiple perspectives for envisioning marine protected areas’ and ‘Co-regulating corporate social responsibility: government response to forest certification in Canada, the United States and Sweden’), the researchers’ reflections and self-evaluation reports still come from a small group. On the other hand, such deep, honest and transparent analysis in describing the steps to the implementation of

Animal Navigation in the Classroom: Lessons From a Pilot Experience

In response to a direct request from science teachers, researchers initiated a pilot experience on animal orientation and navigation, which was delivered to 61 13-year-old students in Florence, Italy. The aim was to explain the approach to ethology and to link animal navigation with geography, focusing on species crossing the Italian territory. Together with the theoretical workshop, an experiment held in the classroom allowed the students to make and test their own hypotheses through an hands-on approach. A questionnaire was submitted before and after the experience to test the effectiveness of the whole activity, and highlight issues relevant to the improvement of school science program. Results indicate an uptake of the concepts and the sharing individual knowledge among the classroom, leading to an overall knowledge increase regarding the species mentioned. This experience indicates that the issue of animal orientation and navigation and helps knowledge integration. The engaging nature of this topic makes it ideal for promoting biological conservation, by focusing attention on species behavior and the habitats where such behavior is displayed. The author found direct collaboration between researchers and teachers to be an effective aid to the formation of the next generation of scientists.

Integration of the Gender Dimension into Socioeconomics Analysis

Men and women carry out different and complementary activities, specially if we consider rural environments. The environmental resources are therefore differently used and perceived with respect to gender, and different needs may emerge. To achieve equality conditions, these features should be considered in a constructive way and in an integrated perspective, avoiding gender segregation also in the theoretical perspective. Women activities and duties are often related to the domestic sphere and, even if essential to the household, generally do not generate money flow, so they may escape the socioenomic approach. A tuning is needed, to give voice to all social components, also considering their different (in space, time, status, power, etc.) scales. This chapter synthetically illustrates how the challenge of gender integration in the socioeconomic analysis was faced throughout the WADI project.