Alien Species Research Articles

Invasive neophytes alter ecological functions and services of riparian hardwood forests

Riparian hardwood forests, now rare in Europe, occur in small patches within agricultural landscapes and are important biodiversity hotspots protected by the EU Habitats Directive and monitored. They play a vital ecological role and provide essential ecosystem services (ES). Recent studies indicate their unfavourable conservation status with a negative trend reported by EU Member States. One of the most visible symptoms of the degradation of riparian hardwood forest is the invasion of alien plant species which can radically change ecosystem functions. In this work, we use plant functional trait analysis to develop proxies and quantify an impact of invasive alien species, specifically invasive neophytes, on specific functions of riparian hardwood forests and their potential to provide five relevant regulating services. Data from 249 phytosociological relevés across 83 Natura 2000 habitat monitoring sites in Poland were analyzed.Our findings indicate that invasive neophytes negatively affect the potential for maintaining nursery populations and habitats, as well as regulation of the chemical condition of freshwaters by these forests. On the other hand, they do not significantly influence the local climate conditions and the forests’ potential to produce antimicrobial compounds. We recommend integrating an ES assessment based on plant functional traits into habitat monitoring. This approach is cost-effective, leveraging existing data, and its results could be used in some cases as a premise for initiating additional environmental monitoring based on direct field measurements.

Phenotypic plasticity as the main driver of alien plant trait variation in urban versus rural microclimate for the model species Veronica persica.

Urban environments are warmer than the rural surroundings, impacting plant phenotypic traits. When plants are present over areas with contrasted conditions such as along urbanization gradients, their phenotypes may differ, and these differencesdepend on different processes, including phenotypic plasticity, maternal environmental effects and genetic differentiation (local adaptation and/or genetic drift). Successful establishment of alien species along environmental gradients has been linked to high phenotypic plasticity and rapid evolutionary responses, which are easier to track for species with a known residence time. The mechanisms explaining trait variation in plants in urban versus rural microclimatic conditions have received little attention. Using the alien Veronica persica as model species, we measured leaf traits in urban and rural populations and performed a reciprocal common-garden experiment to study how germination, leaf, growth, and flowering traits varied in response to experimental microclimate (rural or urban) and population origin environment (rural or urban). Veronica persica displayed phenotypic plasticity in all measured traits, with reduced germination, development, and flowering under urban microclimate which suggests more stressful growing conditions in the urban than in the rural microclimate. No significant effect of the rural or urban origin environment was detected, providing no evidence for local adaptation to urban or rural environments. Additionally, we found limited signs of maternal environmental effects. We noted the importance of the mother plant and the population identities suggesting genetically based differences. Our results indicate that urban environments are more hostile than rural ones, and that V. persica does not show any adaptation to urban environments despite genetic differences between populations.

An Annotated Checklist of Invasive Species of the Phyla Arthropods and Chordates in Panama.

Invasive species are one of the five main causes of biodiversity loss, along with habitat destruction, overexploitation, pollution, and climate change. Numbers and species of invasive organisms represent one of the first barriers to overcome in ecological conservation programs since they are difficult to control and eradicate. Due to the lack of records of invasive exotic species in Panama, this study was necessary for identifying and registering the documented groups of invasive species of the Chordates and Arthropod groups in Panama. This exhaustive search for invasive species was carried out in different bibliographic databases, electronic portals, and scientific journals which addressed the topic at a global level. The results show that approximately 141 invasive exotic species of the Arthropoda and Chordata phyla have been reported in Panama. Of the 141 species, 50 species belonged to the Arthropoda phylum and 91 species belonged to the Chordate phylum. Panamanian economic activity could facilitate the introduction of alien species into the country. This study provides the first list of invasive exotic chordate and arthropod species reported for the Republic of Panama.

Plant diversity conservation issues and challenges: A review

Significant conceptual changes have occurred over the past years in plant conservation, with major methodological advances incorporating modern techniques, technology, and disciplines. The global, national, and regional loss of biodiversity is a multifaceted issue affecting social, economic, organizational, political, scientific, and communicational scenarios. The identification of root causes is key to preventing biodiversity loss. India's diverse ecosystem supports various needs, including food, medicine, clothing, and shelter. Spatial biodiversity assessment is important for prioritizing and monitoring mechanisms and efforts in the context of land use, land cover change, unprecedented overexploitation, uncontrolled pollution, and alien species invasion. Odisha, an eastern Indian state, is rich in natural resources, with tropical moist, and dry deciduous forests covering remote areas of many districts, north-south-western hills, plateaus, and isolated pockets. Conservation efforts have expanded with protected areas, Red Lists, ex-situ facilities, wild plant accessions, and some developed species recovery programs. The conservation community is concerned about how to respond to the continuously depleting bioresources. Conservation prioritization focuses on protecting socioeconomically, medicinally, and environmentally significant species and living communities, regions of high species richness and endemism, and active functional ecosystems. The present review explores how to address sustainable biodiversity conservation practices and natural ecosystems aligning with UN Sustainable Development Goals No. 13 and 15.

Remote Sensing for Mapping Natura 2000 Habitats in the Brière Marshes: Setting Up a Long-Term Monitoring Strategy to Understand Changes

On a global scale, wetlands are suffering from a steady decline in surface area and environmental quality. Protecting them is essential and requires a careful spatialisation of their natural habitats. Traditionally, in our study area, species discrimination for floristic mapping has been achieved through on-site field inventories, but this approach is very time-consuming in these difficult-to-access environments. Usually, the resulting maps are also not spatially exhaustive and are not frequently updated. In this paper, we propose to establish a complete map of the study area using remote sensors and set up a long-term and regular observatory of environmental changes to monitor the evolution of a major French wetland. This methodology combines three dataset acquisition technologies, airborne hyperspectral and WorldView-3 multispectral images, supplemented by LiDAR images, which we compared to evaluate the difference in performances. To do so, we applied the Random Forest supervised classification methods using ground reference areas and compared the out-of-bag score (OOB score) as well as the matrix of confusion resulting from each dataset. Thirteen habitats were discriminated at level 4 of the European Nature Information System (EUNIS) typology, at a spatial resolution of around 1.2 m. We first show that a multispectral image with 19 variables produces results which are almost as good as those produced by a hyperspectral image with 58 variables. The experiment with different features also demonstrates that the use of four bands derived from LiDAR datasets can improve the quality of the classification. Invasive alien species Ludwigia grandiflora and Crassula helmsii were also detected without error which is very interesting when applied to these endangered environments. Therefore, since WV-3 images provide very good results and are easier to acquire than airborne hyperspectral data, we propose to use them going forward for the regular observation of the Brière marshes habitat we initiated.

Rapid spread of the Mediterranean glycophyte Catapodium rigidum in Hungary

This paper discusses the spread of the Mediterranean plant Catapodium rigidum (L.) C.E. Hubb. in Hungary, which is found in the transition zone between the sub-Mediterranean and continental climatic zones of Central Europe. This alien species has been found at 12 new localities in Hungary in recent years. Some of these stands are located along main roads, while others are found in urban weed vegetation. The species was most likely introduced by increasing road traffic and tourism. Our preliminary findings suggest that the spread of the species is not concentrated along main roads due to its salt sensitivity. Instead, it is more likely to be found in xerothermic weed vegetation in urban areas where salting and winter de-icing are not applied.

Enhancing invasive alien plant eradication outcomes: Lessons learned from South Africa

AbstractSeveral attempts to eradicate invasive alien species have been initiated in South Africa and despite no formal eradication declaration, several species have been brought down to low levels or are now absent from the country. Based on an expert workshop with South African implementing agencies on best nationwide eradication practices, we recommend that eradication programmes should be well coordinated, and characterised by collaboration between implementing agencies, researchers and practitioners. Countries should have a list of eradication targets informed by the best available science, with targets ranked according to priority. The best eradication model should be used consistently until eradication is achieved. While most of these priority areas are not novel, it does provide a perspective from a biodiverse African country with limited funding, based on 16 years of experience in implementing eradication programmes. It corroborates challenges experienced elsewhere in the world and contributes to enhancing eradication outcomes globally.

Going urban: variation in personality traits of an invasive species along an urbanization gradient

Abstract The fast-growing expansion of urban areas pose severe pressures on wildlife. However, some generalist native mammals thrive in urbanized landscapes, while invasive alien species (IAS) are often more abundant in cities than in rural habitats. Variation in phenotypes—such as differences in personality traits—can influence the probability to colonize anthropized areas, especially in the case of IAS where certain traits are related to invasion success. Here, we investigated the expression of activity, exploration, and social tendency in the invasive alien Eastern Gray Squirrel (Sciurus carolinensis) in replicated study sites along a rural–urban gradient in Northern Italy. Personality traits expression was estimated using an open field test (OFT) followed by a mirror image stimulation (MIS) test. We found that squirrels were more active in urban than in suburban and rural sites, and behaved more sociable in urban than in suburban sites. Conversely, exploration did not differ along the gradient. Results also reveal the presence of a behavioral syndrome: activity (OFT), social tendency, and activity–exploration (MIS). We suggest that variation in activity level and social behavior in urban habitats could favor some species to respond positively to urbanization. This study sheds light on the underexplored personality–urbanization relationship in IAS, helping to understand the complex process of invasion.

The Effect of Climate on Strongly Disturbed Vegetation of Bait Sites in a Central European Lower Montane Zone, Hungary

Human landscape-transforming activities contribute to the global change in vegetation in different forms. Hunting is one of the most ancient human landscape-shaping activities. Feeders for hunting are particularly disruptive to vegetation. In the present study, we conducted a vegetation survey in these highly disturbed places. We investigated the vegetation dynamics over several years in the turkey oak–sessile oak zone, in two areas with different moisture and shade conditions (forest and clearing). Important background factors are the changes in precipitation and temperature. Our results confirm that weed infestation is detectable at bait sites over a long period. The seasonal changes in field weed vegetation, as well as the increase in the number and coverage of weed species at the end of summer, resulting from lifestyle characteristics, were generally detectable in all years and locations, especially in the case of open and more strongly degraded clearings. Meteorological factors played a role in the degree of weed infestation in each year. Degradation was more significant in drought years, while regeneration was also observed in wetter periods. At baits located in the clearing, we showed a positive correlation between the amount of summer precipitation and the total coverage of weed species, as well as between the average spring temperature and the coverage of certain weed species. With the drying of the climate, the disturbed areas are constantly losing their natural value, but wetter weather is not an automatic solution either. Considering that there are approx. 30,000 bait sites in the country, and they are used regularly and very intensively, they can serve as major infection hotspots for alien species in a network.

A human–wildlife conflict: potential impacts of fatal harvesting approaches on medicinal plants in Free State Province, South Africa

ABSTRACT Human-wildlife conflict has taken center stage in global biodiversity degradation, yet researchers have mainly focused on animals. Medicinal plants are declining globally, partly because of over-harvesting which is considered a form of human-wildlife conflict in this study. Compared with other provinces in South Africa, Free State has limited information on the use of medicinal plants and the impacts of over-harvesting the species. We investigated the potential impacts of over-harvesting the plant species for medicinal purposes and determined the potential conservation implications of the harvesting methods in Free State Province, South Africa. We show that 89 plant species from 43 families were used for traditional medicine. The most-used species were Pachycarpus rigidus (12%; N=211), followed by Dicoma anomala (9%) with the common plant families being Asteraceae (13.5%; N=89), and Fabaceae (7.9%). The perennial herbs were substantially harvested (58.4%; N=89). The wild indigenous plant species were more preferred compared to alien species (79.2%; N=89). The roots and bulbs were mostly utilized for medicinal material (48.3%; N=89), followed by the leaves (20.2%). We found one ‘rare’ species (Schizoglossum montanum), and two ‘nearly threatened’ species (Merwilla plumbea and Eucomis bicolor). We recommend a socio-ecologically orientated policy intervention for the sustainable use of medicinal plants in South Africa.

Macrozoobenthos of The Eastern Gulf of Finland: Current State and Influence on Biogeochemical Processes

Macrozoobenthos plays an important role in biogeochemical processes. In the eastern part of the Gulf of Finland, macrozoobenthos has been changing rapidly in recent decades due to the massive development of alien species of annelids. The current state of benthic communities in the Gulf of Finland is considered based on data at 24 stations in 2019–2021. In open areas of the bay, the biomass of the bivalves Macoma balthica increased as compared to the beginning of the 2010s. The populations of glacial relict crustaceans, which had greatly decreased in the early 2000s due to benthic hypoxia, have practically recovered. The abundance of oligochaetes has also increased due to the spread of the alien species Tubificoides pseudogaster. This led to a decrease in the proportion of alien polychaetes Marenzelleria spp. in the abundance and biomass of macrozoobenthos. Due to differences between species in living and bioturbation activity, the changes that have occurred in the benthos should affect the processes at the water–bottom interface. There is likely to be an increase in the supply of phosphorus from bottom sediments under modern conditions compared to the period of total dominance of polychaetes in benthic communities in the early 2010s.

A morphogenetic characterisation of a potentially dominant African marine species in Europe

Studying the early stages of the introduction of non-indigenous species (NIS) is crucial as it allows immediate management actions aimed at preventing NIS spread at a time when these actions are more likely to be effective. Recent species introductions present unique opportunities to study key aspects of the invasion process. However, comprehensive information on how and when NIS are first introduced remains rare. We assessed the characteristics of the introduction of a member of the widespread Pyura stolonifera species group (Chordata, Tunicata) in Europe. These ascidians are important bioengineer species that can attain amongst the highest benthic biomass per surface area ever reported. We collected introduced individuals on the coast of the northwestern Iberian Peninsula, an area with high shipping traffic and one of the world’s most important mussel farming regions. The specimens were analysed using taxonomic and genetic tools. Both field surveys and taxonomic analysis showed that one of the African members of the species group, Pyura herdmani, has recently been introduced to Europe and, although it does not yet form the large aggregates found in the native range, it is already well-established. Genetic data revealed that only the northwest African lineage of P. herdmani has been introduced to Europe. Considering the low dispersal capabilities of the early life-history stages of P. herdmani, the introduction of this species into Europe can only be explained via human mediated transport of NIS. In order to prevent any detrimental effects on both native biota and/or economically-important anthropogenic activities, regular monitoring of recent NIS introductions is urgently required.

Enhancing global maritime traffic network forecasting with gravity-inspired deep learning models

Aquatic non-indigenous species (NIS) pose significant threats to biodiversity, disrupting ecosystems and inflicting substantial economic damages across agriculture, forestry, and fisheries. Due to the fast growth of global trade and transportation networks, NIS has been introduced and spread unintentionally in new environments. This study develops a new physics-informed model to forecast maritime shipping traffic between port regions worldwide. The predicted information provided by these models, in turn, is used as input for risk assessment of NIS spread through transportation networks to evaluate the capability of our solution. Inspired by the gravity model for international trades, our model considers various factors that influence the likelihood and impact of vessel activities, such as shipping flux density, distance between ports, trade flow, and centrality measures of transportation hubs. Accordingly, this paper introduces transformers to gravity models to rebuild the short- and long-term dependencies that make the risk analysis feasible. Thus, we introduce a physics-inspired framework that achieves an 89% binary accuracy for existing and non-existing trajectories and an 84.8% accuracy for the number of vessels flowing between key port areas, representing more than 10% improvement over the traditional deep-gravity model. Along these lines, this research contributes to a better understanding of NIS risk assessment. It allows policymakers, conservationists, and stakeholders to prioritize management actions by identifying high-risk invasion pathways. Besides, our model is versatile and can include new data sources, making it suitable for assessing international vessel traffic flow in a changing global landscape.

Estimating changes in distribution trend of alien birds in urban areas using citizen science data

Urban ecosystems are suitable for the introduction and spread of alien bird species, and early detection of their establishment and expansion is crucial to reduce potential negative impacts. In this context, the use of opportunistic citizen science data can have considerable advantages in relation to conventional scientific approaches. We gathered records of parakeets and parrots (Psittaciformes) and mynas and starlings (Sturnidae) for the urban area of Lisbon (Portugal) from the eBird database. We used this opportunistic citizen science data to document the establishment and expansion and to estimate distribution trends of alien bird species in urban ecosystems. In the last decade there has been a considerable increase in the amount of opportunistic citizen science data available in eBird for our study area. The probability of presence of the Senegal parrot, rose-ringed parakeet, blue-crowned parakeet, and crested myna was positively influenced by the number of lists. For the rose-ringed parakeet, blue-crowned parakeet, and crested myna, the year positively influenced the probability of presence, suggesting an increase in distribution range. We observed that spatio-temporal variations in effort associated to opportunistic citizen science data sources may generate bias in trend estimates, and therefore we recommend the effort should always be accounted for. Our approach agreed with the documented expansion of alien bird species in the study area, supporting the potential usefulness of opportunistic citizen science in providing early detection on biological invasions in urban ecosystems, particularly where this is the best or the only source of information available.

Microplastics promote the invasiveness of invasive alien species under fluctuating water regime

Abstract Microplastic (MP) pollution and alien plant invasions are two important threats to terrestrial ecosystems. Microplastics alter the physical and chemical characteristics of soil, potentially affecting the performance of alien plants. However, previous studies have overlooked the impact of weather on invasive plants in areas polluted by MPs. With the global increase in extreme rainfall events, it is imperative to redefine the correlation between MPs and invasive plants. Here, we conducted an experiment in a climate chamber to examine the effects of MPs on the growth and development of both native and invasive alien plants under constant and fluctuating water regime (FWR). The FWR simulated extreme water pulses during the 2016–2020 growing seasons in Wuhan, China. Our results indicated that biomass accumulation and root development were influenced by water conditions and MP pollution in both invasive and native species. The extent of the effects varied between the two groups of plant species. FWR promoted plant growth and fine root development in invasive plants but reduced the maximum quantum efficiency of photosystem II (Fv/Fm) and nonphotochemical quenching (NPQ) indices of native plants. Moreover, FWR attenuated the negative effects of polybutylene succinate (PBS, degradable MPs) on biomass and root characteristics (length, surface area and tips). FWR compensated the negative impacts of MPs on the total and below‐ground biomass of the invasive species Paspalum dilatatum and Sphagneticola trilobata, but not on the native species. Consequently, invasive species showed better performance than native species in the fine root development of biomass growth and chlorophyll fluorescence under the combined effects of MPs and FWR. Synthesis and applications. Our findings suggest that MP pollution enhances the competitiveness of invasive alien species over the native species when exposed to pronounced dry–wet water cycle conditions, potentially affecting the composition and biodiversity of the ecosystems. Thus, controlling MP pollution should be a part of the management strategy to conserve biodiversity and ecosystems.

Alien species of nectar-bearing plants of Ukraine’s flora

Alien species pose a significant threat to global biodiversity, competing with local species, gradually displacing them, and often leading to their demise. Alien plants, in particular, pose a direct threat to native plant diversity as well as the management of ecosystems, agriculture, and forestry. The main reason for the appearance of alien species in ecosystems where they are not native is human activity. Most alien plant species have become so due to introduction for cultivation purposes, thanks to their medicinal, honey-producing, and other beneficial properties for humans. Therefore, knowledge of their biology, potential for expansion, as well as possible monitoring and control methods, is extremely important. After all, obtaining the maximum benefit for meeting public needs without harming the environment is an urgent task today. Among alien species, invasive species are the most dangerous for the loss of biodiversity. However, currently in Ukraine, there are no officially approved lists of alien and invasive species, their inventory has not been conducted, monitoring and risk assessment systems are absent, and there are no adequate and coordinated measures to counteract biotic invasions. Therefore, the purpose of our work was to conduct an analysis of the flora of Ukraine, to identify alien, including invasive plants, are honey and/or pollen-producing, and compile their list. As a result of the analysis, 63 alien, including 16 invasive species of vascular plants with honey and pollenproducing properties were identified, belonging to 28 families and 56 genera. Particularly valuable invasive honey plants include: Helianthus annuus L., Robinia pseudoacacia L., Asclepias syriaca L., Paulownia tomentosa (Thunb.) Siebold & Zucc., Solidago canadensis L., which can provide significant industrial honey production. Considering that such invasive plants (which are also honey-producing) as Cucurbita pepo L., Raphanus sativus L., Helianthus annuus L., Juglans nigra L., Prunus armeniaca L. and Vitis vinifera L. are agricultural crops, their spread is usually limited to agricultural lands. Therefore, their invasions into natural ecosystems are minimal, and the benefits are undeniable. However, when cultivating alien plants, it is always worth considering the benefit and economic gain against their real or potential threat to natural ecosystems.

Attributive analysis of the anthropophytes fraction as part of the urban flora of Kyiv urban area (the degree of naturalization, invasive status, threat assessment for local ecosystems and biotic diversity)

International ecological scientific community pays special attention to urbanized territories as separate locations of alien invasive species of biota. The results of the attributive analysis of the structure of the alien fraction of KUA flora according to three current European categories are presented. The basis of the analysis is the final list of alien vascular plants of KUA flora, which contains 718 species. 166 taxa of alien vascular plants that immigrated to KUA from 2003 to 2023 were added to the list. It was found that the degree of naturalization of immigrant species is dominated by casual alien species, which make up 59.0% of the taxonomic composition of the fraction. Species that are elements of man-make environments reach 35.5%. At the same time, alien species that grow and persist for a long time in natural habitats, including protected areas, do not exceed 5.0%. According to the categories of invasive activity, there are species that are naturalized and do not show a tendency to invasions — 32.0%. The most dangerous among invasive plants are transformer species, represented by 2.5%, actual invasive species — 4.0%, potentially invasive species — 2.0%. Based on the «Classification of alien species according to their impact on the environment», adapted by the IUCN: the massive impact is 1.5% of the total number and 4.0% of the number of naturalized ones; accordingly, the major impact — 2.2% (5.4%); the moderate impact — 5.2% (11.2%); the minor impact — 28.1% (68.6%); the minimal impact — 4.2% (10.8%). Based on the results of screening the negative effects of invasive species on the environment, examples of threats are given. This is competition for natural resources, displacement of native plant species; penetration into forests of plants whose climamorphotypes are absent in local forest ecosystems (tree vines), etc. Threatening cases of spontaneous hybridization of immigrant species with local species and with each other have been identified (repeated occurrences in the genera Bidens L., Populus L., Reynoutria Houtt., etc.). The need for an experimental study of the chemical and physical negative effects of invasive plants on local species of biota and human health is indicated. It is noted that the flora of KUA, on the background of the flora of Europe, is currently uniformly affected by phytoinvasions as an urbanized spatial unit of Ukraine.

Invasive fish species in Romanian freshwater. A review of over 100 years of occurrence reports

Effective management of invasive alien species requires location-specific strategies involving the regular update of distribution maps to identify spatial patterns, trends, and pathways of entry and the spread and hotspots of those invasions. However, a comprehensive overview of invasive alien fish species in Romania is lacking. To fill this gap, we compiled a database with occurrences of alien fish species in Romania from diverse sources, including published literature, our own field data, online databases, social media, and online questionnaires. Occurrence data covers the 1910–2022 period. From a total of 52 alien fish species reported as present in Romania’s waterways, we assigned an invasive status to 11 species, of which Pseudorasbora parva, Lepomis gibbosus, Carassius gibelio, and Ameiurus spp. are widespread. Based on the currently available occurrence records, we evaluated the presence and distribution of invasive alien fish species at the watershed level, concluding that invasive alien fish species are present in all Romanian watersheds. We identified several hotspots consistent with the main points of entry and spread of invasive alien fish species, principally located in western, central, and eastern Romania, i.e., Mures, Crisuri, and Siret watersheds.

Anthropogenic forests simplify seed- but not pollen-dispersal networks.

Natural native forests are rapidly being replaced by anthropogenic forests often with a strong presence of invasive alien plant species. Eucalypt species are widely planted worldwide, with Eucalyptus globulus plantations being particularly expressive in Portugal. Poor forestry practices often lead to the associated expansion of invasive species, such as Acacia dealbata. However, we still know relatively little about the functioning of anthropogenic forests, such as seed and pollen dispersal services. Here, we compared bird abundance and richness and the seed and pollen dispersal networks in both forest types. Anthropogenic forests presented lower bird abundance, and smaller, more simplified, and more random (abundance-based) seed dispersal services than those of natural forests. Interestingly, the pollen dispersal network was more similar than the seed dispersal network for both forest types and dominated by opportunistic and neutral processes, given the absence of specialized nectarivorous. The proportion of birds transporting seeds decreased, while those carrying pollen significantly increased in the anthropogenic forest compared to the native forest. Our work highlights the impact of anthropogenic forests on bird abundance, with consequences for seed dispersal services and forest regeneration.

Development and Succession of Non-Indigenous and Cryptogenic Species over Two Different Substrates in the Port of Alicante (Western Mediterranean)

Artificial structures act as points of entry for non-indigenous species (NIS) in port areas and may support higher abundance and richness of them. The studies about NIS are increasing, but studies focusing on the variations in temporal recruitment and ecological mechanisms are still scarce. Thus, the aim of this work was to determine the colonization and development of non-indigenous sessile fouling species over two types of substrates (electrolytic carbonated and steel) during 12 months of immersion in the Alicante harbor. The biofouling communities of both substrates were analyzed in terms of abundance and species richness by status (native, cryptogenic, and NIS), and NIS assemblages of both substrates were studied by means of multivariate analyses. In total, 53 different species were identified, 38 in steel (six NIS and six cryptogenic) and 50 in the carbonated substrate (six NIS and 10 cryptogenic). Most NIS were more abundant and diverse after 9 months of immersion and had a preference for carbonated substrates. Furthermore, most of them were positively correlated in both substrates (mainly in steel) and it is noted that the number of NIS in the port of Alicante is increasing as new records have been detected.