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16 pages, 5 figures, 4 tables, supplementary material https://www.frontiersin.org/articles/10.3389/fmars.2021.698890/full#supplementary-material.-- Data Availability Statement: The original contributions presented in the study are included in the article/Supplementary Material, further inquiries can be directed to the corresponding author, Benthic habitats of the deep Mediterranean Sea and the biodiversity they host are increasingly jeopardized by increasing human pressures, both direct and indirect, which encompass fisheries, chemical and acoustic pollution, littering, oil and gas exploration and production and marine infrastructures (i.e., cable and pipeline laying), and bioprospecting. To this, is added the pervasive and growing effects of human-induced perturbations of the climate system. International frameworks provide foundations for the protection of deep-sea ecosystems, but the lack of standardized criteria for the identification of areas deserving protection, insufficient legislative instruments and poor implementation hinder an efficient set up in practical terms. Here, we discuss the international legal frameworks and management measures in relation to the status of habitats and key species in the deep Mediterranean Basin. By comparing the results of a multi-criteria decision analysis (MCDA) and of expert evaluation (EE), we identify priority deep-sea areas for conservation and select five criteria for the designation of future protected areas in the deep Mediterranean Sea. Our results indicate that areas (1) with high ecological relevance (e.g., hosting endemic and locally endangered species and rare habitats),(2) ensuring shelf-slope connectivity (e.g., submarine canyons), and (3) subject to current and foreseeable intense anthropogenic impacts, should be prioritized for conservation. The results presented here provide an ecosystem-based conservation strategy for designating priority areas for protection in the deep Mediterranean Sea, This study was supported by the DG ENV project IDEM (Implementation of the MSFD to the Deep Mediterranean Sea; contract EU No. 11.0661/2017/750680/SUB/EN V.C2). MC and QG-B acknowledge support from Generalitat de Catalunya autonomous government through its funding scheme to excellence research groups (Grant 2017 SGR 315), With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)

Invasive alien species threaten biodiversity and ecosystem structure and functioning, but incomplete assessments of their origins and temporal trends impair our ability to understand the relative importance of different factors driving invasion success. Continuous time-series are needed to assess invasion dynamics, but such data are usually difficult to obtain, especially in the case of small-sized taxa that may remain undetected for several decades. In this study, we show how micropaleontologic analysis of sedimentary cores coupled with radiometric dating can be used to date the first arrival and to reconstruct temporal trends of foraminiferal species, focusing on the alien Amphistegina lobifera and its cryptogenic congener A. lessonii in the Maltese Islands. Our results show that the two species had reached the Central Mediterranean Sea several decades earlier than reported in the literature, with considerable implications for all previous hypotheses of their spreading patterns and rates. By relating the population dynamics of the two foraminifera with trends in sea surface temperature, we document a strong relationship between sea warming and population outbreaks of both species. We conclude that the micropaleontologic approach is a reliable procedure for reconstructing the bioinvasion dynamics of taxa having mineralized remains, and can be added to the toolkit for studying invasions., peer-reviewed

Limited research effort in the Central Mediterranean deep sea has reported a lower species diversity in this area than in adjacent regions. With the recent advent of remotely operated underwater vehicles (ROVs), the deep sea has become more accessible to surveys, especially rocky benthic areas such as canyons and escarpments. The aim of the present study was to assess diversity, spatial and bathymetric distribution, density, habitat, and microhabitat associations of echinoderms in deep waters around the Maltese Islands. Video data were acquired through ROV surveys as part of the LIFE BaĦAR for N2K project, at depths of 216 to 1031 m. In total, 25 echinoderm taxa were recorded, including the first Central Mediterranean records of the sea stars Marginaster capreensis (Gasco, 1876) and Sclerasterias neglecta (Perrier, 1891), and the first record of the holothuroid Mesothuria intestinalis (Ascanius, 1805) from Maltese waters. Six species were observed deeper than their currently accepted depth range in the Mediterranean. The most abundant species were the crinoids Antedon mediterranea (Lamarck, 1816) and Leptometra phalangium (Muller, 1841), which formed very dense aggregations of up to 2900 individuals/1000 m2 in a small area to the south of Malta. This area also supports the only known Mediterranean population of the Atlantic sea star Coronaster briareus (Verrill, 1882). Bathymetric distribution varied for each species, and the overall echinoderm diversity seemed stable across the surveyed depths. Since previous deep-sea studies in the area were based on trawling surveys, many deep-sea echinoderm species are reported in the literature as occurring on sedimentary bottoms. However, the present study revealed that several occur more often on rocky substrata, corals, or anthropogenic objects than on sediments. Our study based on video footage also provided insights into the microhabitat of many deep-sea species, yielding information that is not obtainable through remote sampling.

Bonnici, L.; Borg, J.A.; Evans, J.; Lanfranco, S., and Schembri, P.J., 2018. Of rocks and hard places: Comparing biotic assemblages on concrete jetties versus natural rock along a microtidal Mediterranean shore. The species composition and structure of littoral assemblages on concrete jetties were compared with those on natural rocky shores at two localities on the microtidal NE coast of Malta. Algal species richness and total algal biomass were significantly lower on jetties. Faunal species richness and faunal abundance were also lower on jetties, albeit not significantly so. Jetties and natural rocky shores differed in relative species composition. The algae Palisada perforata/Laurencia obtusa and several mobile animals, mostly crustaceans, molluscs, and polychaetes, were more abundant on rocky shores. In particular, the supralittoral gastropod Melarhaphe neritoides had a density ranging between 8 ind./m2 to 98 ind./m2 on rocky shores but was never recorded on jetties. Conversely, the algae Cla...

The doctorfish Acanthurus chirurgus (Bloch, 1787) is reported for the first time from the central Mediterranean, based on a specimen caught in Maltese waters during August 2016. Since the only previous Mediterranean record of this species was based on a single individual observed in the Tyrrhenian Sea, the present record likely represents an independent introduction that may have occurred through the aquarium trade or via shipping. Two other surgeonfish species, Acanthurus coeruleus Bloch and Schneider, 1801 and Acanthurus monroviae Steindachner, 1876, were previously recorded from the central Mediterranean. While A. coeruleus may have established a population in the Levantine Sea, like A. chirurgus it has only been reported once from Malta (and from the central Mediterranean in general); both A. coeruleus and A. chirurgus are, therefore, considered to be casual species in Maltese waters. In contrast, A. monroviae was reported from several Mediterranean countries including Tunisia and Malta in the central Mediterranean. Here we present several authenticated reports of this species from Maltese waters, which strongly suggest that it has managed to establish a population in this region, although the possibility of multiple introductions cannot be excluded., peer-reviewed

The sea star Coronaster briareus (Verrill Am J Sci (Ser III), 1882) is reported for the first time from the Mediterranean Sea. A total of 26 individuals were sighted in Maltese waters during ROV surveys made in July 2015 and June–July 2016. The identity of the species was confirmed through morphological examination of a specimen collected in June 2016. This identification is discussed in the light of inconsistencies in the published descriptions of species of Coronaster recorded from the Atlantic, and of individuals belonging to this genus recorded from the eastern Atlantic and whose coloration does not match that of C. briareus or C. volsellatus (the only species of Coronaster hitherto known from the Atlantic). The presence of numerous individuals of C. briareus in Maltese waters, recorded on two occasions a year apart over a relatively large area, indicates that there is an established population. This represents a considerable expansion of the distribution range of this species, which is mostly known from the western Atlantic. Possible reasons for its presence in Maltese waters are discussed, but the dynamics of the occurrence of C. briareus in the central Mediterranean remain unknown., peer-reviewed

The earliest records of cold-water corals from the Mediterranean Sea date back to the eighteenth century when Linnaeus first described Madrepora oculata based on specimens from the central Mediterranean and Tyrrhenian Sea. It was only towards the end of the nineteenth century that cold-water corals were recorded from elsewhere in the Mediterranean, thanks to early research cruises that explored the Mediterranean deep-sea benthos. Although the first records of live cold-water corals date back to the early twentieth century, further observations of living individuals were extremely rare and most records made by the end of the century were actually based on dead or fossil fragments. This led to the idea that extant Mediterranean cold-water coral assemblages are merely relicts of the communities that thrived during the Pleistocene. However, several sites with live framework-forming cold-water coral species were discovered since the year 2000, including six regions identified as cold-water coral provinces given that they support a dense growth of living corals. The emerging picture is that thriving cold-water coral assemblages that are hotspots of deep-sea biodiversity still occur in the Mediterranean, but have a rather punctuate distribution along the circulation path of the Levantine Intermediate Water, which appears to be a main driver for cold-water coral distribution in the Mediterranean.

Refined baseline inventories of non-indigenous species (NIS) are set per European Union Member State (MS), in the context of the Marine Strategy Framework Directive (MSFD). The inventories are based on the initial assessment of the MSFD (2012) and the updated data of the European Alien Species Information Network, in collaboration with NIS experts appointed by the MSs. The analysis revealed that a large number of NIS was not reported from the initial assessments. Moreover, several NIS initially listed are currently considered as native in Europe or were proven to be historical misreportings. The refined baseline inventories constitute a milestone for the MSFD Descriptor 2 implementation, providing an improved basis for reporting new NIS introductions, facilitating the MSFD D2 assessment. In addition, the inventories can help MSs in the establishment of monitoring systems of targeted NIS, and foster cooperation on monitoring of NIS across or within shared marine subregions., peer-reviewed

Recent deep-water remotely operated vehicle surveys around the Maltese Islands resulted in the discovery of highly diverse habitats, including extensive hard bottom areas dominated by gorgonians and living cold-water corals with a rich variety of associated fauna. Black coral (Leiopathes glaberrima) forests were dominant at 200–400 m, whilst stony reef-forming corals (in particular Madrepora oculata) were most abundant in waters deeper than 500 m. The gorgonian Callogorgia verticillata was dominant in places over the entire depth range, but was particularly abundant at depths of 800–1000 m. Such cold-water coral assemblages are of high conservation interest, and offshore marine protected areas are urgently required in order to protect these very diverse, but highly vulnerable, deep-sea habitats.

This study updates the current distribution, range expansion and establishment status of the non-indigenous species Amphistegina lobifera Larsen, 1976 and other foraminifera that are cryptogenic in the Sicily Channel. Prior to this study, amphisteginids were reported from the Levantine Basin, the Central Mediterranean (Tunisia, Malta, Pelagian islands) and the southern Adriatic Sea. Here, we provide new records documenting a north-western expansion in the Central Mediterranean. In summer-autumn 2017 and spring-summer 2018, we collected algae and sediment samples from shallow coastal habitats along the shores of the Maltese archipelago, southern and north-western Sicily, Pantelleria and the Aegadian islands. Analysis of the foraminiferal assemblages showed that A. lobifera is effectively established around Malta and in southern/south-eastern Sicily, and has reached the oceanographic boundary between the Central and Western Mediterranean. Our results also show that the thermotolerant A. lobifera is at an advanced stage of invasion in the Sicily Channel, probably favoured by a recent rise in Mediterranean sea surface temperatures. New species distribution models are provided for the years 2040–2050 and 2090–2100, indicating that the predicted warming trend will facilitate north-westward migration of Mediterranean amphisteginids along the coast of northern Africa into the Alboran Sea, and deep into the Adriatic Sea.

The accumulation of large boulders related to waves generated by either tsunamis or extreme storm events have been observed in different areas of the Mediterranean Sea. Along the eastern low-lying rocky coasts of Malta, five sites with large boulder deposits have been investigated, mea- sured and mapped. These boulders have been detached and moved from the nearshore and the lowest parts of the coast by sea wave action. In the Sicily–Malta channel, heavy storms are common and originate from the NE and NW winds. Con- versely, few tsunamis have been recorded in historical docu- ments to have reached the Maltese archipelago. We present a multi-disciplinary study, which aims to de- fine the characteristics of these boulder accumulations, in or- der to assess the coastal geo-hazard implications triggered by the sheer ability of extreme waves to detach and move large rocky blocks inland. The wave heights required to transport 77 coastal boul- ders were calculated using various hydrodynamic equations. Particular attention was given to the quantification of the in- put parameters required in the workings of these equations, such as size, density and distance from the coast. In addition, accelerator mass spectrometry (AMS) 14C ages were deter- mined from selected samples of marine organisms encrusted on some of the coastal boulders. The combination of the re- sults obtained both by the hydrodynamic equations, which provided values comparable with those observed and mea- sured during the storms, and radiocarbon dating suggests that the majority of the boulders have been detached and moved by intense storm waves. These boulders testify to the exis- tence of a real hazard for the coasts of Malta, i.e. that of very high storm waves, which, during exceptional storms, are able to detach large blocks of volumes exceeding 10 m3 from the coastal edge and the nearshore bottom, and also to transport them inland. Nevertheless, the occurrence of one or more tsunami events cannot be ruled out, since radiocarbon dat- ing of some marine organisms did reveal ages which may be related to historically known tsunamis in the Mediterranean region, such as the ones in AD 963, 1329, 1693 and 1743., peer-reviewed

The only species of Cephalopholis currently known from the Mediterranean is Cephalopholis taeniops (Valenciennes, 1828), which was recorded from Libya, Malta, and Lampedusa after having autochthonously extended its original Atlantic range. All records of Cephalopholis substantiated by specimens or images from Malta were evaluated, showing that an individual filmed in August 2009 was misidentified and instead represents the first record of Cephalopholis hemistiktos (Rüppell, 1830) from the Mediterranean. Based on these records, C. taeniops is considered to be established in Maltese waters while C. hemistiktos is regarded as a ‘casual’ species, most likely transported by shipping or introduced as an aquarium escapee., peer-reviewed

Summary The incidence of damage caused by grey squirrels in the Turin plain was studied to assess the impact this alien species is having on the highly fragmented Piedmont environment, in particular on profi table cereals, poplar plantations and semi-natural woodlands. The survey of damage was conducted both by interviews to local farmers and growers and by direct assessment using the Nearest Neighbour Method on plantations and woodlands, studying randomly chosen plots in the Turin plain to gain a general overview of the situation. The results show a low incidence of damage caused by grey squirrels in the area: little or none was found in semi-natural woodlands and in agricultural crops, apart from maize where less than 1 per cent of fi elds showed damage, and poplar plantations where 5 per cent had signs of bark stripping. Damage on maize crops was random across the plain, but debarking damage to poplars was mostly concentrated on the western side of the plain, and tended to occur only in particular years. Damage was concentrated close to streams and rivers surrounding fi elds and plantations. The introduction of the grey squirrel in Italy has already caused ecological damage such as the extinction of the red squirrel in some areas. Nevertheless, little or no information is available on the damage this species is causing on woodlands or agricultural areas. This study is a preliminary survey in order to fi ll this gap.

Many changes have occurred over the last 70 years: broadleaves no longer exceed conifers in area and coppice has declined markedly. While we see many neglected woods, especially on farms, the depressingly poor quality of much oak which Guillebaud laments is not now viewed so seriously. Today, broadleaves are grown for a wider variety of objectives and not just for fine timber. While excellent stem form remains highly desirable, achieving it is not so critical where amenity, conservation or landscape objectives are uppermost. A major advance since Guillebaud's time is more rapid establishment owing to herbicides and tree shelters though we still plant broadleaves too far apart. Natural regeneration is again being encouraged but we now have to add grey squirrels and muntjac deer causing severe depredations besides the animals Guillebaud listed. Broadleaves have a much more favourable press today because they are favoured for many more uses than simply timber production. This shift is the greatest contrast with 70 years ago and the greatest influence on what silvicultural practices to adopt.

The solitary ascidian Herdmania momus, an Indo-Pacific species that has been introduced into the Mediterranean Sea via the Suez Canal during the past century, has so far been restricted to the Levantine region. Here we record H. momus from the Maltese Islands, which represents a considerable westwards expansion of the species’ distribution range in the Mediterranean. Possible modes of introduction are discussed, with translocation of adults via shipping and subsequent spawning at destina- tion sites deemed a plausible mechanism., peer-reviewed

Planting trees in tropical countries is becoming an increasingly important forestry activity as many tropical countries that depended on wood supply from natural forests are recognizing the need to establish plantations to augment supplies from dwindling and unsustainable natural forests. The total area of tropical forest plantations increased from about 6.7 million ha in 1965 to 109 million in 2005. Though most species used for tropical plantations are fast growing, their growth rate can be improved substantially through appropriate silviculture such as site-species matching, site nutrient management, use of hybrid species (clonal plantation), etc. This chapter reviews recent advances in tropical forest plantation establishment and management. Subjects that were specifically covered include: extent of tropical forest plantations, principles of productive forest plantation establishment and management, growth and yield of important tree species, silvicultural techniques for improvement of growth, impact of new aspects for silviculture, etc. Two insightful and demonstrative case studies were also presented to illustrate key points.

The alien dendronotacean nudibranch Melibe viridis (Kelaart, 1858), a tropical Indo-Pacific species that seems to have been introduced by shipping into the Mediterranean via the Suez Canal, and which has established populations in Greece, Turkey, Cyprus, Montenegro, Croatia, NW Sicily, southern peninsular Italy and Djerba Island in the Gulf of Gabes, is recorded for the first time from Malta. A thriving population was observed on a soft sediment bottom at a depth of 18-20 m off the western coast of the island of Comino (Maltese Islands). It is suggested that this species was introduced into Malta due to a natural range expansion of surrounding populations., peer-reviewed

Effective forest management today requires planning and design to meet landscape, wildlife conservation and recreation objectives. Diversity is acknowledged to be the key to many aspects of improve...

Planting trees in tropical countries is an increasingly important forestry activity. Although much attention has been paid, and rightly so, to rapid deforestation in the tropics, the contribution and role that planted forests can play are now at the center of policy and planning in most national forestry strategies. The changing emphasis from exploitative management of natural forests to managed natural forests and plantation forests, seen in temperate regions over the last 100 years, has been taking place in tropical countries largely over the last 20 years. In neither temperate nor tropical regions has this evolution finished.

SUMMARY An increasing dependence is likely on fast-growing plantations in the tropics to meet the rising world demand for wood and wood products. With the use often of exotic species in pure stands, grown on short rotations, a possible problem will be the maintenance of productivity in successive crops. This subject is reviewed in the light of experience elsewhere, the occurrence of a confirmed second-rotation decline in yield in South Australia, and the author's research in Swaziland. So far there is insufficient evidence for assuming that declining yields will occur in successive rotations of plantations, but the possibility is very real on some sites. This must act as a warning against undue dependence on plantations, and to foresters that greater inputs of improved cultural practice, fertilisers and better genetic varieties may be needed as such forestry practice approaches ‘tree farming’.

Plantation forestry in the tropics today is characterised by increasing refinement of matching species with site and increasing emphasis on non-industrial purposes for growing trees. The forester is called upon to satisfy many more objectives, environmental and social as well as industrial, and this leads to a need to reappraise choice of species. It is not sufficient to cultivate the trees which grow best, with a reasonably amenable industry using his product, but to grow species suited to the villagers' needs or the requirements of erosion control. The variety of site types for tree planting in the tropics is widening. This includes restocking as well as new planting, agroforestry opportunities and planting around farms, increasing needs to reforest eroding lands, and the challenge of preventing the complete transition from forest to grassland, by judicious tree planting before grass dominates, of the millions of hectares affected by over-intesive shifting cultivation. Priorities and perspectives are changing as the value placed on trees and tree cover increases. It remains essential to silviculture that species and sites are matched but the resulting forest must be appropriate for the job, whether product grown, behefit conferred or both.