Demographics of the zooxanthellate coral Oculina patagonica along the Mediterranean Iberian coast in relation to environmental parameters

Selection of mesophotic habitats by Oculina patagonica in the Eastern Mediterranean Sea following global warming

Globally, species are migrating in an attempt to track optimal isotherms as climate change increasingly warms existing habitats. Stony corals are severely threatened by anthropogenic warming, which has resulted in repeated mass bleaching and mortality events. Since corals are sessile as adults and with a relatively old age of sexual maturity, they are slow to latitudinally migrate, but corals may also migrate vertically to deeper, cooler reefs. Herein we describe vertical migration of the Mediterranean coral Oculina patagonica from less than 10 m depth to > 30 m. We suggest that this range shift is a response to rapidly warming sea surface temperatures on the Israeli Mediterranean coastline. In contrast to the vast latitudinal distance required to track temperature change, this species has migrated deeper where summer water temperatures are up to 2 °C cooler. Comparisons of physiology, morphology, trophic position, symbiont type, and photochemistry between deep and shallow conspecifics revealed only a few depth-specific differences. At this study site, shallow colonies typically inhabit low light environments (caves, crevices) and have a facultative relationship with photosymbionts. We suggest that this existing phenotype aided colonization of the mesophotic zone. This observation highlights the potential for other marine species to vertically migrate.

Who’s Next? Non-Indigenous Cnidarian and Ctenophoran Species Approaching to the Italian Waters

The aims of the present paper were to review the knowledge about the Mediterranean non-indigenous species of the taxa Cnidaria and Ctenophora (CC NIS), to screen the risk of 98 species for their potential invasiveness in the Mediterranean Sea and their approach to the Italian waters. Of these, 38% are well established in the basin, 4% are known for their invasiveness, 44% are casual, 11% have a taxonomic status unresolved, and 3% are included in the category ”cryptogenic”. The biodiversity CC NIS of the Mediterranean Sea has changed considerably in the last two decades and 27 out of 98 Mediterranean CC NIS are present in the Italian waters. Fifteen CC NIS, some equipped with high invasive potential, should be regarded as good candidates to become future immigrants of the Italian waters. Anticipatory NIS forecast based on biogeographical and ecological analyses may provide a useful tool for targeted management of the CC NIS issue and for the assessment of the second descriptor of Good Environmental Status. On the other hand, conservation and management of marine ecosystem should be based on the conservation of the essential environmental conditions for the functioning of these ecosystems instead of the contamination or eradication of alien species.

Overview and trends of ecological and socioeconomic research on artificial reefs

It is presented a systematic literature review of artificial reef research, including 620 studies throughout the world from 1962 to 2018. The primary focus of this study was to examine long-term trends in research, focusing on ecological and socioeconomic questions, and to develop new research directions for this field. From 1962 to the beginning of the 1990s, the United States and Japan were the main centers of artificial reef research. Subsequently, researchers in several other countries (particularly China, Australia, Italy, Brazil, and the United Kingdom) began to focus on this subject, resulting in an increase in the number of artificial reef studies. In general, publications about artificial reefs have concentrated on investigating the structure of populations and marine communities and evaluating new technical designs and materials to construct artificial habitats. The science of artificial reefs is responding to new challenges with an increase in more elaborate techniques, such as the use of remotely-operated submarines, organic indicators, isotopes, and molecular biology, while research that evaluates the socioeconomic aspects of artificial reefs is lacking. There are many aspects that deserve more research attention, such as the use of alternative inert materials, environmental impact assessment and mitigation, and analysis of conflicts with affected fisheries communities. The greater challenge is to overcome the apparent division between theory vs. application and to include robust management models of these artificial environments.