Strangers in a strange land: do life history traits differ for alien and native colonisers of novel environments?

Do alien invasive species exhibit life history characteristics that are similar to those of native species that have become pests in their continent of origin? We compared eucalypt specialists that have become pests in Australian plantations (natives) to those that have established overseas (aliens) using 13 life history traits and found that although traits that support rapid population build-up were shared, overall, aliens and native colonisers differed significantly. Distance from source (New Zealand vs. other) had no significant effect, but species that established more than 50 years ago exhibited different life history traits from those that established within the last 50 years, possibly because of more effective quarantine. Native and alien eucalypt insect invaders differed predominantly in traits that facilitate long-distance movement (pathway traits), compared to traits that facilitate establishment and spread. Aliens had longer adult flight seasons, were smaller and more closely host-associated (cryptic eggs and larvae), had lower incidence of diapause (i.e. were more seasonally plastic) and more generations per year than natives. Thus, studies of species invasive within their country of origin can shed light on alien invasions.

Global change and climate-driven invasion of the Pacific oyster (Crassostrea gigas) along European coasts: a bioenergetics modelling approach

Aim The spread of non-indigenous species in marine ecosystems world-wide is one of today's most serious environmental concerns. Using mechanistic modelling, we investigated how global change relates to the invasion of European coasts by a non-native marine invertebrate, the Pacific oyster Crassostrea gigas. Location Bourgneuf Bay on the French Atlantic coast was considered as the northern boundary of C. gigas expansion at the time of its introduction to Europe in the 1970s. From this latitudinal reference, variations in the spatial distribution of the C. gigas reproductive niche were analysed along the north-western European coast from Gibraltar to Norway. Methods The effects of environmental variations on C. gigas physiology and phenology were studied using a bioenergetics model based on Dynamic Energy Budget theory. The model was forced with environmental time series including in situ phytoplankton data, and satellite data of sea surface temperature and suspended particulate matter concentration. Results Simulation outputs were successfully validated against in situ oyster growth data. In Bourgneuf Bay, the rise in seawater temperature and phytoplankton concentration has increased C. gigas reproductive effort and led to precocious spawning periods since the 1960s. At the European scale, seawater temperature increase caused a drastic northward shift (1400 km within 30 years) in the C. gigas reproductive niche and optimal thermal conditions for early life stage development. Main conclusions We demonstrated that the poleward expansion of the invasive species C. gigas is related to global warming and increase in phytoplankton abundance. The combination of mechanistic bioenergetics modelling with in situ and satellite environmental data is a valuable framework for ecosystem studies. It offers a generic approach to analyse historical geographical shifts and to predict the biogeographical changes expected to occur in a climate-changing world.

Evaluation of the antioxidant activity and antitumor activity of marine invertebrates extracts

Dissertação de Mestrado, Biologia Marinha, Faculdade de Ciências e Tecnologias, Universidade do Algarve, 2014

The history of the introduction of the giant river prawn, Macrobrachium cf. rosenbergii (Decapoda, Palaemonidae), in Brazil: new insights from molecular data

The giant river prawn, Macrobrachium cf. rosenbergii, is one of the most cultivated freshwater prawns in the world and has been introduced into more than 40 countries. In some countries, this prawn is considered an invasive species that requires close monitoring. Recent changes in the taxonomy of this species (separation of M. rosenbergii and M. dacqueti) require a re-evaluation of introduced taxa. In this work, molecular analyses were used to determine which of these two species was introduced into Brazil and to establish the geographic origin of the introduced populations that have invaded Amazonian coastal waters. The species introduced into Brazil was M. dacqueti through two introduction events involving prawns originating from Vietnam and either Bangladesh or Thailand. These origins differ from historical reports of the introductions and underline the need to confirm the origin of other exotic populations around the world. The invading populations in Amazonia require monitoring not only because the biodiversity of this region may be affected by the introduction, but also because admixture of different native haplotypes can increase the genetic variability and the likelihood of persistence of the invading species in new habitats.

Measuring the Impact of Melaleuca quinquenervia Biochar Application on Soil Quality, Plant Growth, and Microbial Gas Flux

Biochar has been heralded a mechanism for carbon sequestration and an ideal amendment for improving soil quality. Melaleuca quinquenervia is an aggressive and wide-spread invasive species in Florida. The purpose of this research was to convert M. quinquenervia biomass into biochar and measure how application at two rates (2% or 5% wt/wt) impacts soil quality, plant growth, and microbial gas flux in a greenhouse experiment using Phaseolus vulgaris L. and local soil. Plant growth was measured using height, biomass weight, specific leaf area, and root-shoot ratio. Soil quality was evaluated according to nutrient content and water holding capacity. Microbial respiration, as carbon dioxide (CO2), was measured using gas chromatography. Biochar addition at 5% significantly reduced available soil nutrients, while 2% biochar application increased almost all nutrients. Plant biomass was highest in the control group, p2 flux decreased significantly in both biochar groups, but reductions were not long term.

Non-indigenous Japanese oyster drill Pteropurpura (Ocinebrellus) inornata (Récluz, 1851) (Gastropoda: Muricidae) on the south-west coast of Portugal

The Japanese oyster drill or rock snail Pteropurpura (Ocinebrellus) inornata (Récluz, 1851), a marine mollusc, belonging to the family Muricidae, is reported from Portugal for the first time. This non-indigenous species, most likely introduced accidentally from French oyster rearing areas into mainland Portugal, has been regularly sampled in shellfish-culture and nearby environments in Sagres, Algarve, Southwest Portugal since 2005–2008. Detailed studies are urgently needed in order to assess whether or not it has become an invasive species due to a range expansion beyond its point of initial introduction. Outputs should provide information to decision-makers to predict and limit further spread which might result in biodiversity loss and negative economical consequences in locally species-rich areas.

Age and growth of the smooth hammerhead shark, Sphyrna zygaena, in the Eastern Equatorial Atlantic Ocean, using vertebral sections

The smooth hammerhead shark Sphyrna zygaena (Sphyrnidae) is regularly caught as bycatch in pelagic longline fisheries, but is one of the least studied of all pelagic sharks. Recently, ICCAT (International Commission for the Conservation of Atlantic Tunas) issued recommendations underlining the need for more studies on the life history parameters of this and other pelagic shark species. To this end, the age and growth of S. zygaena were studied in the Eastern Equatorial Atlantic Ocean, in an area where growth parameters were not yet available for this species. Data from 139 specimens, caught between June and September 2009, ranging in size from 136 to 233 cm fork length (FL), were analysed. Preliminary trials were carried out to assess the most efficient growth band enhancement technique. These indicated that sectioning the vertebrae into 500 μm sections followed by staining with crystal violet produced the best results. Growth models were fitted using the traditional von Bertalanffy growth equation and a modification of this equation using a known size at birth. Growth models were compared using the Akaike information criterion (AIC). The von Bertalanffy growth equation seemed to be the most adequate model to describe growth in this species, with resulting growth parameters of L inf = 272 cm FL, k = 0.06 year for males and L inf = 285 cm FL, k = 0.07 year for females. In the first four years of life, S. zygaena grows 25 cm per year on average, but its growth slows down in later life. Future stock assessment models should incorporate these age and growth parameters for species management and conservation.

The role of anglers' perceptions and habits in biological invasions: perspectives from the Iberian Peninsula

Anglers are a recognized vector for invasive fauna, with both intentional and accidental introductions reported worldwide. * The purpose of this study was to investigate the Iberian freshwater angler's habits and perceptions related to biological invasions, using an international and bilingual survey in Spain and Portugal. * The results showed that anglers from both countries cover great distances to fish, and that they commonly visit several places and fish during consecutive days, representing a major risk for invasions. Yet, anglers' activity patterns throughout the year are not constant: the summer months involve more intense activity and, hence, entail higher risk. * In both countries, the preferred fish species were invasive, and their introductions were reported more often than native species, with motivations being country-dependent. * The use of live bait was not frequent, but sometimes invasive species were used and the release of unused bait in the water was reported very frequently. * Most anglers recognize that introductions have environmental impacts and that anglers have an active role in intentional introductions. However, only a minority is aware of the angler's role in accidental transportation of invasive species. * These findings on anglers' behaviour patterns and perceptions may be used to model invasion risks and also improve monitoring and awareness programmes led by government agencies.

Hovenia dulcis (uva-do-japão) no sul do Brasil: invasão, cultura e alteração da paisagem.

Resumo: Em virtude dos impactos ambientais causados, as espécies exóticas invasoras (EEl's) tem se tornado foco de muitos estudos nas Ciências Biológicas. Entretanto, muitas EEl's tem a sua presença não evitada em novos ambientes, pois o homem e, muitas vezes, o principal vetor de dispersão, especial mente de espécies de plantas invasoras. Neste trabalho, e discutida a hipótese de uma forte influencia cultural na introdução/expansão da uva-do-Japão nesta região e o problemático cenário de invasão da espécie no sul do Brasil. Palavras-chave: espécies exóticas invasoras (EEl's); alteração da paisagem; Hovenia dulcis (uva-do-japão); cultura. Abstract: Invasive species (IS) have become focus on many studies in Biological Sciences because of environmental damages. However, the presence of lAS's is not prevented in new areas, because humans are often the main vector of dispersion, especially invasive plant species. In this work, the hypothesis of a strong cultural influence is discussed on the introduction/expansion of Japanese raisin tree in this region and the problematic scenario of invasion in southern Brazil. Keywords: invasive species (IS's); landscape changes; Hovenia dulcis ; (Japanese raisin tree); culture.

The role of angler’s perceptions and habits in biological invasions: Perspectives from Iberian Peninsula

1. Anglers are a recognized vector for invasive fauna, with both intentional and accidental introductions reported worldwide. 2. The purpose of this study 2. The purpose of this study was to investigate the Iberian freshwater angler’s habits and perceptions related to biological invasions, using an international and bilingual survey in Spain and Portugal. 3. The results showed that anglers from both countries cover great distances to fish, and that they commonly visit several places and fish during consecutive days, representing a major risk for invasions. Yet, anglers’ activity patterns throughout the year are not constant: the summer months involve more intense activity and, hence, entail higher risk. 4. In both countries, the preferred fish species were invasive, and their introductions were reported more often than native species, with motivations being country-dependent. 5. The use of live bait was not frequent, but sometimes invasive species were used and the release of unused bait in the water was reported very frequently. 6. Most anglers recognize that introductions have environmental impacts and that anglers have an active role in intentional introductions. However, only a minority is aware of the angler’s role in accidental transportation of invasive species. 7. These findings on anglers’ behaviour patterns and perceptions may be used to model invasion risks and also improve monitoring and awareness programmes led by government agencies.

Plantas invasoras no sul de Portugal: uma abordagem biogeográfica

As espécies invasoras são uma das principais ameaças à biodiversidade causando impactes ecológicos, económicos e nos serviços dos ecossistemas. O conhecimento conjunto da dinâmica das séries de vegetação e da ecologia das plantas invasoras é uma ferramenta útil na recuperação ecológica de áreas invadidas e na prevenção de invasões. Este trabalho tem como objectivo principal averiguar a relação entre a distribuição das plantas invasoras e as comunidades vegetais terrestres do Sul de Portugal. Para tal, fez-se corresponder a distribuição de nove plantas invasoras selecionadas com as séries de vegetação e territórios biogeográficos, em 60 quadrículas com 1 Km2. A Província Lusitana-Andaluza Costeira revelou-se a mais invadida, com predomínio de Acacia dealbata, Acacia longifolia e Opuntia maxima no potencial climatófilo de sobreiral psamófilo; A. longifolia dominou no potencial edafoxerófilo de zimbral de Juniperus turbinata e A. dealbata e Arundo donax no potencial edafo-higrófilo de freixial. Com base nos resultados, estabeleceram-se áreas prioritárias para intervenção; INVASIVE PLANTS IN SOUTHERN PORTUGAL A BIOGEOGRAPHICAL APPROACH Abstract: Invasive species are one of the main threats to biodiversity worldwide and are responsible for negative impacts at ecological, economic and ecosystem services level. Complementarity between vegetation series dynamics and invasive plants ecology knowledge is essential to address ecological restoration and to prevent invasions. The main goal of this work is to investigate the relationship between invasive plants distribution and terrestrial plant communities of Southern Portugal. Fieldwork was conducted in 60 1 Km2 sampling plots and a correspondence was made between nine selected invasive plants and the vegetation series and the biogegraphic units The Andalusian-Lusitanian Coastal province was the most invaded biogeographic unit and revealed the dominance of Acacia dealbata, Acacia longifolia and Opuntia maxima in the cork oak psammophilous series; A. longifolia dominated in the maritime turbinate juniper edapho-xerophilous series and A. dealbata and Arundo donax in the ash edaphohygrophilous groves potential. Based on the results, priority areas for intervention were defined.

Recovering Functional Integrity in Pastures Dominated by an Invasive Grass Species

Exotic grasses have been introduced in countries worldwide for pasture improvement, soil stabilisation and ornamental purposes. Some of these introductions have proven successful, but many have not (Cook & Dias 2006). In Australia, the Commonwealth Plant Introduction Scheme was initiated in 1929, and over-time introduced more than 5000 species of grasses, legumes and other forage and browse plants (Cook & Dias 2006). Lonsdale (1994) suggested that, in tropical Australia, 13% of introductions have become a problem, with only 5% being considered useful for agriculture. Low (1997) suggested that 5 out of 18 of Australia's worst tropical environmental weeds were intentionally introduced as pasture grasses. The spread and dominance of invasive grass species that degrade the quality of pastures for production can impact significantly on the livelihoods of small proprietors. Although Livestock grazing contributes only a small percentage to the world's GDP (1.5%), maintaining the long-term stability of this industry is crucial because of the high social and environmental consequence of a collapse. One billion of the world's poor are dependent on livestock grazing for food and income with this industry occupying more than 25% of the world's land base (Steinfeld et al. 2006). The ling-term sustainability of livestock grazing is also crucial for the environment. A recent FAO report attributed livestock production as a major cause of five of the most serious environmental problems: global warming, land degredation, air and water pollution, and the loss of biodiversity (Steinfeld et al. 2006). For these reasons, finding more effective approaches that guide the sustainable management of pastures is urgently needed. In Australia more than 55% of land use is for livestock grazing by sheelp and/or cattle. This land use dominate in the semi-arid and arid regions where rainfall and soil conditions are marginal for production (Commonwealth of Australia 2004). Although the level of agriculture production by conglomerates is increasing, the majority of livestock grazing within Australia remains family owned and operated (Commonwealth of Australia 2004). The sustainability of production from a grazed pasture is dependent on its botanical composition (Kemp & Dowling 1991, Kemp et al. 1996). In a grazed pasture, the dominance of an invasive grass species can impact on the functional integrity of the ecosystem, including production and nutrient cycling; wwhich will in turn, affect the income of proprietors and the ability of the system to recover from disturbance and environmental change. In Australia, $0.3 billion is spent on weed control in livestock production, but despite this substantial investment $1.9 billion is still lost in yield as a result of weeds (Sinden et al. 2004). In this paper, we adaprt a framework proposed for the restoration of degraded rainforest communities (Lamb & Gilmour 2003, Lamb et al. 2005) to compare and contrast options for recovering function integrity (i.e. a diverse set of desirable plant species that maintain key ecological processes necessary for sustainable production and nutrient cycling) within pasture communities dominated by an invasive grass species. To do this, we uase a case-study of the invasion of Eragrostis curvula (Africal lovegrss; hereafter, Lovegrass), a serious concern in Australian agricultural communities (Parsons and Cuthbertson 1992). The spread and dominance of Lovegrass is a problem because its low palatability, low nutritional content and competitiveness affect the livelihood of graziers by reducing the diversity of other plant species. We conclude by suggesting modifications to this framework for pasture ecosystems to help increase the effiency of strategies to protect functional integrity and balance social/economic and biodiversity values.

Priority threat management of invasive animals to protect biodiversity under climate change

Climate change is a major threat to global biodiversity, and its impacts can act synergistically to heighten the severity of other threats. Most research on projecting species range shifts under climate change has not been translated to informing priority management strategies on the ground. We develop a prioritization framework to assess strategies for managing threats to biodiversity under climate change and apply it to the management of invasive animal species across one-sixth of the Australian continent, the Lake Eyre Basin. We collected information from key stakeholders and experts on the impacts of invasive animals on 148 of the region's most threatened species and 11 potential strategies. Assisted by models of current distributions of threatened species and their projected distributions, experts estimated the cost, feasibility, and potential benefits of each strategy for improving the persistence of threatened species with and without climate change. We discover that the relative cost-effectiveness of invasive animal control strategies is robust to climate change, with the management of feral pigs being the highest priority for conserving threatened species overall. Complementary sets of strategies to protect as many threatened species as possible under limited budgets change when climate change is considered, with additional strategies required to avoid impending extinctions from the region. Overall, we find that the ranking of strategies by cost-effectiveness was relatively unaffected by including climate change into decision-making, even though the benefits of the strategies were lower. Future climate conditions and impacts on range shifts become most important to consider when designing comprehensive management plans for the control of invasive animals under limited budgets to maximize the number of threatened species that can be protected.

Predicting risk and benefit a priori in biological control of invasive plant species: a systems modelling approach

While the method using specialist herbivores in managing invasive plants (classical biological control) is regarded as relatively safe and cost-effective in comparison to other methods of management, the rarity of strict monophagy among insect herbivores illustrates that, like any management option, biological control is not risk-free. The challenge for classical biological control is therefore to predict risks and benefits a priori. In this study we develop a simulation model that may aid in this process. We use this model to predict the risks and benefits of introducing the chrysomelid beetle Charidotis auroguttata to manage the invasive liana Macfadyena unguis-cati in Australia. Preliminary host-specificity testing of this herbivore indicated that there was limited feeding on a non-target plant, although the non-target was only able to sustain some transitions of the life cycle of the herbivore. The model includes herbivore, target and non-target life history and incorporates spillover dynamics of populations of this herbivore from the target to the non-target under a variety of scenarios. Data from studies of this herbivore in the native range and under quarantine were used to parameterize the model and predict the relative risks and benefits of this herbivore when the target and non-target plants co-occur. Key model outputs include population dynamics on target (apparent benefit) and non-target (apparent risk) and fitness consequences to the target (actual benefit) and non-target plant (actual risk) of herbivore damage. The model predicted that risk to the non-target became unacceptable (i.e. significant negative effects on fitness) when the ratio of target to non-target in a given patch ranged from 1:1 to 3:2. By comparing the current known distribution of the non-target and the predicted distribution of the target we were able to identify regions in Australia where the agent may be pose an unacceptable risk. By considering risk and benefit simultaneously, we highlight how such a simulation modelling approach can assist scientists and regulators in making more objective decisions a priori, on the value of releasing specialist herbivores as biological control agents.