Networks of global bird invasion altered by regional trade ban

Assessing the ecological and societal impacts of alien parrots in Europe using a transparent and inclusive evidence-mapping scheme

Globally, the number of invasive alien species (IAS) continues to increase and management and policy responses typically need to be adopted before conclusive empirical evidence on their environmental and socioeconomic impacts are available. Consequently, numerous protocols exist for assessing IAS impacts and differ considerably in which evidence they include. However, inclusive strategies for building a transparent evidence base underlying IAS impact assessments are lacking, potentially affecting our ability to reliably identify priority IAS. Using alien parrots in Europe as a case study, here we apply an evidence-mapping scheme to classify impact evidence and evaluate the consequences of accepting different subsets of available evidence on impact assessment outcomes. We collected environmental and socioeconomic impact data in multiple languages using a “wiki-review” process, comprising a systematic evidence search and an online editing and consultation phase. Evidence was classified by parrot species, impact category (e.g. infrastructure), geographical area (e.g. native range), source type (e.g. peer-review), study design (e.g. experimental) and impact direction (deleterious, beneficial and no impact). Our comprehensive database comprised 386 impact entries from 233 sources. Most evidence was anecdotal (50%). A total of 42% of entries reported damage to agriculture (mainly in native ranges), while within Europe most entries concerned interspecific competition (39%). We demonstrate that the types of evidence included in assessments can strongly influence impact severity scores. For example, including evidence from the native range or anecdotal evidence resulted in an overall switch from minimal-moderate to moderate-major overall impact scores. We advise using such an evidence-mapping approach to create an inclusive and updatable database as the foundation for more transparent IAS impact assessments. When openly shared, such evidence-mapping can help better inform IAS research, management and policy.

Mediterranean versus Atlantic monk parakeets Myiopsitta monachus: towards differentiated management at the European scale

BACKGROUND

The monk parakeet Myiopsitta monachus (Boddaert), native to South America, is an invasive species in several European countries, causing crop damage and potential negative impacts on wildlife. Only Spain and Great Britain have regulations to control monk parakeets, thus fast growth and spread of populations are likely to occur on a wide scale. The aims of this research are to update information on the distribution and population size of monk parakeets in Europe, assess whether differences in population growth or spread rate exist between populations, and provide recommendations to decision-makers.

RESULTS

Our study estimates that there are 23 758 monk parakeets in the wild, across 179 municipalities in eight European Union (EU) countries; 84% of these municipalities hold between 1 and 100 monk parakeets. All countries with a representative historical record are experiencing exponential growth of monk parakeets. Mediterranean countries are experiencing higher exponential growth, spread rate and faster colonization of new municipalities than Atlantic countries.

CONCLUSIONS

We recommend that EU Mediterranean countries consider declaration of the monk parakeet as invasive alien species of regional concern, and develop coordinated efforts to monitor and manage the species, taking advantage of the low population sizes in most municipalities. © 2019 Society of Chemical Industry.

Risks of Biological Invasion on the Belt and Road

China's Belt and Road Initiative (BRI) is an unprecedented global development program that involves nearly half of the world's countries [1]. It not only will have economic and political influences, but also may generate multiple environmental challenges and is a focus of considerable academic and public concerns [2-6]. The Chinese government expects BRI to be a sustainable development, paying equal attention to economic development and environmental conservation [7]. However, BRI's high expenditure on infrastructure construction, by accelerating trade and transportation, is likely to promote alien species invasions [5], one of the primary anthropogenic threats to global biodiversity [8]. BRI countries may have different susceptibilities to invasive species due to different financial and response capacities [9]. Moreover, these countries overlap 27 of 35 recognized global biodiversity hotspots [10]. Identifying those areas with high-invasion risks, and species with high invasive potentials within BRI countries, is therefore of vital importance for the sustainable implementation of the BRI, and the development of early, economical, and effective biosecurity strategies [11]. In response, we present here a comprehensive study to evaluate invasion risks by alien vertebrates within BRI. We identified a total of 14 invasion hotspots, the majority of which fall along the six proposed BRI economic corridors, with the proportion of grid cells in invasion hotspots 1.6 times higher than other regions. Based on our results, we recommend the initiation of a project targeting early prevention, strict surveillance, rapid response, and effective control of alien species in BRI countries to ensure that this development is sustainable.

Dealing in deadly pathogens: Taking stock of the legal trade in live wildlife and potential risks to human health

Zoonotic diseases cause millions of deaths every year. Diseases such as Ebola, severe acute respiratory syndrome (SARS), and avian influenza cause economic losses at the global level and jeopardize diplomatic relations between countries. As wildlife are the source of at least 70% of all emerging diseases and given the on-going concerns associated with wildlife trade as a disease transmission mechanism, we provide a 'global snapshot' of the legal trade in live wild animals and take stock of the potential health risks that it poses to global human health. Our analysis showed that 11,569,796 individual live wild animals, representing 1316 different species were exported from 189 different countries between 2012 and 2016. China was the largest exporter of live mammals (with 98,979 animals representing 58.7% of global trade). Nicaragua was the largest exporter of live amphibians (with 122,592 animals representing 53.8% of global trade). South Africa was the largest exporter of live birds (with 889,607 animals representing 39.2% of global trade). Peru was the largest exporter of live reptiles (with 1,675,490 animals representing 18.8% of global trade). Our analysis showed that mostly the USA and other high-income countries, the largest importers, drive the live animal trade. High-income countries and not the countries where wildlife diseases and pathogens are more likely to occur reported almost all of the disease reports to the World Organisation for Animal Health. Based on our findings, we discuss how maximising trade bans; working on human behaviour change and improving regulatory efforts to improve surveillance will decrease the risk of future pandemics, epidemics and outbreaks.

Models of alien species richness show moderate predictive accuracy and poor transferability

Robust predictions of alien species richness are useful to assess global biodiversity change. Nevertheless, the capacity to predict spatial patterns of alien species richness remains largely unassessed. Using 22 data sets of alien species richness from diverse taxonomic groups and covering various parts of the world, we evaluated whether different statistical models were able to provide useful predictions of absolute and relative alien species richness, as a function of explanatory variables representing geographical, environmental and socio-economic factors. Five state-of-the-art count data modelling techniques were used and compared: Poisson and negative binomial generalised linear models (GLMs), multivariate adaptive regression splines (MARS), random forests (RF) and boosted regression trees (BRT). We found that predictions of absolute alien species richness had a low to moderate accuracy in the region where the models were developed and a consistently poor accuracy in new regions. Predictions of relative richness performed in a superior manner in both geographical settings, but still were not good. Flexible tree ensembles-type techniques (RF and BRT) were shown to be significantly better in modelling alien species richness than parametric linear models (such as GLM), despite the latter being more commonly applied for this purpose. Importantly, the poor spatial transferability of models also warrants caution in assuming the generality of the relationships they identify, e.g. by applying projections under future scenario conditions. Ultimately, our results strongly suggest that predictability of spatial variation in richness of alien species richness is limited. The somewhat more robust ability to rank regions according to the number of aliens they have (i.e. relative richness), suggests that models of aliens species richness may be useful for prioritising and comparing regions, but not for predicting exact species numbers.