Life-history trait of the Mediterranean keystone species Patella rustica: growth and microbial bioerosion

The age and shell growth patterns in populations of Patella rustica of the Adriatic Sea were determined by analyzing the inner growth lines visible in shell sections. Marginal increment analysis showed annual periodicity with annual growth line being deposited in May. The growth analysis of 120 individual shells showed that 90.8 % of collected individuals were less than 4 years of age and only two individuals (1.6 %) were older than 6 years. Population structure was described and the generalized von Bertalanffy growth parameters were calculated: asymptotic length (L∞) was 38.22 mm and the growth constant (K) was 0.30 year-1. Growth performance index value of P. rustica (Ø’) was 2.64 and is among the lowest ranges reported for limpet species. Patella rustica shells were degraded to different degrees by microbial bioerosion. Microboring organisms identified were pseudofilamentous and filamentous cyanobacteria Hormathonema paulocellulare, Hyella caespitosa, Mastigocoleus testarum and Leptolyngbya sp. The overall intensity of infestation was relatively low, but increased in severity with shell length. The damage was most often restricted to the oldest parts of the shell, i.e. apex of the shell, posing difficulties in determining the exact position of the first growth line. The present study is first to introduce the use of inner growth lines in Patella rustica shell sections as a reliable method for age determination and it provides the first insight into the growth patterns of this keystone species while taking the interference of microbial shell bioerosion in consideration

An energy budget for the subtidal bivalve Modiolus barbatus (Mollusca) at different temperatures

Clearance rates, respiration rates and food absorption efficiencies of the commercially interesting subtidal bivalve Modiolus barbatus were measured at different temperatures under laboratory conditions and scope for growth calculated. Clearance rates were highest at temperatures from 20°C to 28°C, whereas respiration rate was maximal at 9°C and minimal at 26°C. Highest mean values of absorbed energy occurred at 20°C and 26°C. Scope for growth trend had negative values at 9°C, 15°C and 28°C and positive values at temperatures 20°C and 26°C. The profitable thermal window for M. barbatus to have energy sufficient for growth and reproduction corresponded to <5 months per year. Seawater temperature increases will potentially impact the ecophysiological responses of subtidal M. barbatus causing life history traits to change with important repercussions for subtidal biodiversity in the Mediterranea

Nature-Inclusive Design: a catalogue for offshore wind infrastructure : Technical report

Offshore wind farms in the Dutch North Sea must make demonstrable efforts to stimulate native nature within the wind farm. For example, suitable scour protection or fish hotels can be placed around wind turbines that serve as nursery areas or offer shelter. Also flat oysters can be placed, which can form reefs and attract great biodiversity. Commissioned by the Ministry of Agriculture, Nature and Food Quality, Witteveen+Bos and Wageningen Marine Research have produced a catalog of such Nature Inclusive Design options. The catalog shows the target species for which the option is suitable, the expected construction costs, and where the materials can be purchased

Nature-Inclusive Design: a catalogue for offshore wind infrastructure : Technical report

Offshore wind farms in the Dutch North Sea must make demonstrable efforts to stimulate native nature within the wind farm. For example, suitable scour protection or fish hotels can be placed around wind turbines that serve as nursery areas or offer shelter. Also flat oysters can be placed, which can form reefs and attract great biodiversity. Commissioned by the Ministry of Agriculture, Nature and Food Quality, Witteveen+Bos and Wageningen Marine Research have produced a catalog of such Nature Inclusive Design options. The catalog shows the target species for which the option is suitable, the expected construction costs, and where the materials can be purchased

Adaptations to thermal variation in two Mediterranean limpets - cardiac response and haemocyte lysosomal stability

Patella rustica and Patella caerulea are two congeneric limpet species, both occurring along the rocky shores of the Mediterranean but on different tidal heights. P. rustica is dominant in the upper intertidal zone while P. caerulea is more abundant in the lower part of the same zone. Understanding variations in physiological adaptations to thermal stress is vital when investigating intertidal species' distribution. Hence, to investigate the relationship between their physiological thermal tolerance and intertidal zonation, laboratory experiments were designed to test the hypothesis that the lower zoned P. caerulea has reduced upper thermal limits when compared with higher zoned P. rustica, which is predicted to be more tolerant. Arrhenius break temperatures (ABTs) of cardiac performance were used as a sensitive parameter to estimate species critical thermal limits, together with analysis of haemocyte lysosomal stability, and both in line with the concept of oxygen and capacity - limited thermal toleranc

Taking the acid test: Mediterranean limpets face up to climate change

Impacts of climate change involve the interactions of multiple stressors on intertidal organisms, but rarely are the impacts of these stressors examined together. Many tests are also conducted in artificial, controlled laboratory conditions, without making use of natural opportunities to test performance of organisms under different environmental stressors. Given its small tidal range, the Mediterranean Sea provides such an opportunity, with a very fine scale environmental gradient and species living very close to each other over the tidal gradient. The vertical distribution of the limpets, Patella rustica and P. caerulea overlap in Palermo, Sicily, but despite this they have different thermal windows. The higher shore P. rustica had a lower metabolic rate than the mid shore P. caerulea, and was also more tolerant of thermal stress, being able to maintain heart function up to 38°C as opposed to 36°C in P. caerulea. When heat stressed, P. rustica also induced heat shock protein expression, whereas expression in P. caerulea was very low. Utilizing a natural gradient of seawater pH (caused by CO2 vents off Vulcano Island, Sicily), the combined effects of ocean acidification and thermal stress were investigated, which revealed an intraspecific gradient in species response. In general both species were more tolerant of thermal stress, maintaining heart rates between 41- 43°C, but individuals stressed by lower pH were less tolerant as compared to those further from the vent which experienced natural seawater pH. Heat shock protein expression and function of metabolic enzymes were also analyzed. These preliminary findings highlight the need for testing the impacts of multiple stressors, but also the benefits of utilizing naturally occurring habitats to investigate the interactions between environmental stressors

The impact of climate change on mediterranean intertidal communities: losses in coastal ecosystem integrity and services

As has been shown for other ecosystems, the ecological and socio-economic impacts of climate change on Mediterranean intertidal habitats are highly variable in space and time. We conducted field and laboratory measurements of cellular, ecophysiological and behavioural responses of selected intertidal invertebrates (mussels, gastropods and sponges) and completed a literature review to determine what is known of socio-economic consequences of these biological changes. Results suggest significant gaps in our knowledge that may impede a complete understanding of likely impacts (physical, biological and socio-economic) and that sufficient data for such an analysis are available only for mussels. Application of ecological models for native mussels Mytilaster minimus and invasive Brachidontes pharaonis bivalves indicates that the current distribution of these species is linked to the availability of food and local temperature. Choosing Israel as a case study, the study focused on the identification of ecosystem services and goods provided by the Mediterranean rocky intertidal and on the assessment of conservation approaches. Intertidal systems were poorly represented in the socio-economic literature, and there was low awareness of the value of these ecosystems among stakeholders. Subsequently, conservation efforts for intertidal communities were minimal. While climate change will very likely continue to impact these systems, our predictive capacity for the extent and locations of such impacts, and of any derived socio-economic consequences, remains limited. © 2012 Springer-Verlag Berlin Heidelberg.link_to_subscribed_fulltex

The impact of climate change on mediterranean intertidal communities: losses in coastal ecosystem integrity and services

Abstract As has been shown for other ecosystems, the ecological and socio-economic impacts of climate change on Mediterranean intertidal habitats are highly variable in space and time. We conducted field and laboratory measurements of cellular, ecophysiological and behavioural responses of selected intertidal invertebrates (mussels, gastropods and sponges) and completed a literature review to determine what is known of socio-economic consequences of these biological changes. Results suggest significant gaps in our knowledge that may impede a complete understanding of likely impacts (physical, biological and socio-economic) and that sufficient data for such an analysis are available only for mussels. Application of ecological models for native mussels Mytilaster minimus and invasive Brachidontes pharaonis bivalves indicates that the current distribution of these species is linked to the availability of food and local temperature. Choosing Israel as a case study, the study focused on the identification of ecosystem services and goods provided by the Mediterranean rocky intertidal and on the assessment of conservation approaches. Intertidal systems were poorly represented in the socio-economic literature, and there was low awareness of the value of these ecosystems among stakeholders. Subsequently, conservation efforts for intertidal communities were minimal. While climate change will very likely continue 123 Reg Environ Change (2014) 14 (Suppl 1):S5-S17 DOI 10.1007/s10113-012-0360-z to impact these systems, our predictive capacity for the extent and locations of such impacts, and of any derived socio-economic consequences, remains limited