João Canning-Clode

Classification of Non-Indigenous Species Based on Their Impacts: Considerations for Application in Marine Management

Assessment of the ecological and economic/societal impacts of the introduction of non-indigenous species (NIS) is one of the primary focus areas of bioinvasion science in terrestrial and aquatic environments, and is considered essential to management. A classification system of NIS, based on the magnitude of their environmental impacts, was recently proposed to assist management. Here, we consider the potential application of this classification scheme to the marine environment, and offer a complementary framework focussing on value sets in order to explicitly address marine management concerns. Since existing data on marine NIS impacts are scarce and successful marine removals are rare, we propose that management of marine NIS adopt a precautionary approach, which not only would emphasise preventing new incursions through pre-border and at-border controls but also should influence the categorisation of impacts. The study of marine invasion impacts requires urgent attention and significant investment, since we lack the luxury of waiting for the knowledge base to be acquired before the window of opportunity closes for feasible management.

The Effects of Copper Pollution on Fouling Assemblage Diversity: A Tropical-Temperate Comparison

Background The invasion of habitats by non-indigenous species (NIS) occurs at a global scale and can generate significant ecological, evolutionary, economic and social consequences. Estuarine and coastal ecosystems are particularly vulnerable to pollution from numerous sources due to years of human-induced degradation and shipping. Pollution is considered as a class of disturbance with anthropogenic roots and recent studies have concluded that high frequencies of disturbance may facilitate invasions by increasing the availability of resources. Methodology/Principal Findings To examine the effects of heavy metal pollution as disturbance in shaping patterns of exotic versus native diversity in marine fouling communities we exposed fouling communities to different concentrations of copper in one temperate (Virginia) and one tropical (Panama) region. Diversity was categorized as total, native and non-indigenous and we also incorporated taxonomic and functional richness. Our findings indicate that total fouling diversity decreased with increasing copper pollution, whether taxonomic or functional diversity is considered. Both native and non-indigenous richness decreased with increasing copper concentrations at the tropical site whereas at the temperate site, non-indigenous richness was too low to detect any effect. Conclusions/Significance Non-indigenous richness decreased with increasing metal concentrations, contradicting previous investigations that evaluate the influence of heavy metal pollution on diversity and invasibility of fouling assemblages. These results provide first insights on how the invasive species pool in a certain region may play a key role in the disturbance vs. non-indigenous diversity relationship.

'Caribbean Creep' chills out: climate change and marine invasive species.

Background New marine invasions have been recorded in increasing numbers along the worlds coasts due in part to the warming of the oceans and the ability of many invasive marine species to tolerate a broader thermal range than native species. Several marine invertebrate species have invaded the U.S. southern and mid-Atlantic coast from the Caribbean and this poleward range expansion has been termed ‘Caribbean Creep’. While models have predicted the continued decline of global biodiversity over the next 100 years due to global climate change, few studies have examined the episodic impacts of prolonged cold events that could impact species range expansions. Methodology/Principal Findings A pronounced cold spell occurred in January 2010 in the U.S. southern and mid-Atlantic coast and resulted in the mortality of several terrestrial and marine species. To experimentally test whether cold-water temperatures may have caused the disappearance of one species of the ‘Caribbean Creep’ we exposed the non-native crab Petrolisthes armatus to different thermal treatments that mimicked abnormal and severe winter temperatures. Our findings indicate that Petrolisthes armatus cannot tolerate prolonged and extreme cold temperatures (4–6°C) and suggest that aperiodic cold winters may be a critical ‘reset’ mechanism that will limit the range expansion of other ‘Caribbean Creep’ species. Conclusions/Significance We suggest that temperature ‘aberrations’ such as ‘cold snaps’ are an important and overlooked part of climate change. These climate fluctuations should be accounted for in future studies and models, particularly with reference to introduced subtropical and tropical species and predictions of both rates of invasion and rates of unidirectional geographic expansion.

First record of Celleporaria brunnea (Bryozoa: Lepraliellidae) in Portugal and in the East Atlantic

Bryozoans are common fouling species present on ships and artificial substrates. A number of projects reporting the presence of bryozoans in Portugal have been carried out in recent years. As part of a field survey to examine and quantify the non-indigenous marine fouling species in several marinas in Portugal, we detected the bryozoan Celleporaria brunnea for the first time. The native range of C. brunnea seems to extend from British Columbia to the Galapagos, Ecuador. Our discovery indicates that this is the first record of C. brunnea across the East Atlantic and the first record of a species in this genus in the north-eastern Atlantic. The fouling nature of Celleporaria brunnea may have facilitated its spread to the western Pacific, the Mediterranean and now the eastern Atlantic from the Americas.

Diversity of Bugulidae (Bryozoa, Cheilostomata) colonizing artificial substrates in the Madeira Archipelago (NE Atlantic Ocean)

Until very recently the Madeira Archipelago registered a total of eight Bugulidae species. In the present study we include descriptions of seven Bugulidae species, now with Scanning Electron Microscopy images, with four new records for the Archipelago: Bugulina fulva and Bugulina simplex for Madeira Island and Bugula neritina and Crisularia gracilis for the neighbouring Island of Porto Santo. Furthermore, we report the correction of the previous identification of Bugulina calathus minor earlier reported from Funchal harbour in 1998, now as Bugulina flabellata. This study is part of an ongoing monitoring program for detecting non-indigenous species in all marinas from the Madeira archipelago, between 2007 and 2015. Specimens were collected in previously deployed PVC settling plates, marina pontoons, and also on recreational hull vessels while performing dry dock inspections at a local shipyard. Our study reveals that the Madeira archipelago now registers a total of ten Bugulidae species, contributing therefore to the total bryozoan fauna of the Archipelago, now with more than 100 records. These numbers could increase, as Madeira is considered to be a “hotspot” for bryozoan diversity when compared to other nearby regions. Finally, hull fouling is considered as the most likely vector of introduction for the non-indigenous species of Bugulidae detected in Madeira.

New species and new records of bryozoans from shallow waters of Madeira Island

Two new species of bryozoans encrusting subtidal rocks are described from the shallow waters of Madeira Island. We describe one cyclostome, Favosipora purpurea sp. nov., which represents the first record of this genus in the Atlantic Ocean, and one cheilostome, Rhynchozoon papuliferum sp. nov. In addition, one species, Beania maxilladentata, is recorded for the first time outside of Rio de Janeiro, Brazil. Six other species previously recorded in Madeira are redescribed to provide new data and SEM images.

First record of the non-indigenous isopods Paracerceis sculpta (Holmes, 1904) and Sphaeroma walkeri Stebbing, 1905 (Isopoda, Sphaeromatidae) for Madeira Island

While exploring the presence of non-indigenous fouling species colonizing settlement plates deployed in local marinas in Madeira Island (north-eastern Atlantic Ocean), two non-indigenous species (NIS) of free-swimming crustaceans, Paracerceis sculpta (Holmes, 1904) and Sphaeroma walkeri Stebbing, 1905 (Isopoda: Sphaeromatidae), were detected. Paracerceis sculpta is native to the Pacific Coast of North and Central America and has been introduced into many other regions worldwide. Sphaeroma walkeri is native to the northern Indian Ocean and nowadays is considered one of the most widely ship-transported species globally. Both species were collected in the marina of Funchal, Madeira Island, Portugal, during monitoring surveys in 2015. Moreover, several specimens of S. walkeri were also found in a foreign recreational yacht hull, during a dry dock inspection. These findings suggest that hull fouling is a significant vector for the introductions of marine invertebrates into the Madeira island system.

Three non-indigenous species from Madeira harbors, including a new species of Parasmittina (Bryozoa)

During a study investigating the identity and abundance of fouling non-indigenous species in marinas from the Madeira Archipelago, three species of bryozoans were detected on experimental settlement plates. These three species are described and figured. Celleporaria inaudita was previously only known from Vanuatu (South Pacific Ocean) and Safaga Bay (Red Sea). Parasmittina alba was previously only known from the Brazilian coast. The origin of Parasmitina multiaviculata sp. nov. is unknown. Secondary introduction by anthropogenic vectors (via hull fouling of recreational vessels) seems the most plausible explanation for the presence of these species in the Madeira Islands.

Marine protected communities against biological invasions: A case study from an offshore island

Biological invasions are a major threat to the worlds biota and are considered a major cause of biodiversity loss. Therefore, world marine policy has recognized the need for more marine protected areas (MPAs) as a major tool for biodiversity conservation. The present work experimentally evaluated how protected communities from an offshore island can face the settlement and/or expansion of nonindigenous species (NIS). First, NIS colonization success in marine protected and marina communities was compared by deploying PVC settling plates at the Garajau MPA and Funchal marina (SW Madeira Island). Then, the settling plates from the MPA were transferred to Funchal marina to test their resistance to NIS invasion under high levels of NIS pressure. Results indicated that the structure and composition of fouling communities from the MPA differed from those collected in the marina. Interestingly, communities from the protected area showed lower NIS colonization success, suggesting some degree of biotic resistance against NIS invasion.

What's in a tide pool? Just as much food web network complexity as in large open ecosystems

Understanding the fundamental laws that govern complex food web networks over large ecosystems presents high costs and oftentimes unsurmountable logistical challenges. This way, it is crucial to find smaller systems that can be used as proxy food webs. Intertidal rock pool environments harbour particularly high biodiversity over small areas. This study aimed to analyse their food web networks to investigate their potential as proxies of larger ecosystems for food web networks research. Highly resolved food webs were compiled for 116 intertidal rock pools from cold, temperate, subtropical and tropical regions, to ensure a wide representation of environmental variability. The network properties of these food webs were compared to that of estuaries, lakes and rivers, as well as marine and terrestrial ecosystems (46 previously published complex food webs). The intertidal rock pool food webs analysed presented properties that were in the same range as the previously published food webs. The niche model predictive success was remarkably high (73–88%) and similar to that previously found for much larger marine and terrestrial food webs. By using a large-scale sampling effort covering 116 intertidal rock pools in several biogeographic regions, this study showed, for the first time, that intertidal rock pools encompass food webs that share fundamental organizational characteristics with food webs from markedly different, larger, open and abiotically stable ecosystems. As small, self-contained habitats, intertidal rock pools are particularly tractable systems and therefore a large number of food webs can be examined with relatively low sampling effort. This study shows, for the first time that they can be useful models for the understanding of universal processes that regulate the complex network organization of food webs, which are harder or impossible to investigate in larger, open ecosystems, due to high costs and logistical difficulties.