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Suppression of established populations of invasive alien species can be a complex and expensive process, which is frequently unsuccessful. The Asian clam, Corbicula fluminea (Müller, 1774), is considered a high impact invader that can adversely alter freshwater ecosystems and decrease their socioeconomic value. To date, C. fluminea continues to spread and persist within freshwater environments worldwide, despite repeated management attempts to prevent dispersal and suppress established populations. As extensive C. fluminea beds can often become exposed during low-water conditions, the direct application of hot or cold thermal shock treatments has been proposed as suitable mechanism for their control. Further, mechanical substrate disturbance may enhance the efficacy of thermal shock treatments by facilitating exposures to multiple layers of buried clams. In the present study, we advanced these methods by assessing combined applications of both hot and cold thermal shock treatments for control of C. fluminea, using steam spray (≥100 °C; 350 kPa), low- or high-intensity open-flame burns (~1000 °C) and dry ice (−78 °C). In a direct comparison of raking combined with hot thermal shock applications, both steam and high-intensity open-flame treatments tended to be most effective, especially following multiple applications. In addition, when hot thermal treatments are followed by a final cold shock (i.e. dry ice), steam treatments tended to be most effective. Further, when dry ice was applied either alone or prior to an application of a hot shock treatment, substantial if not complete C. fluminea mortality was observed. Overall, this study demonstrated that combined applications of hot and cold thermal shock treatments, applied following the disruption of the substrate, can substantially increase C. fluminea mortality compared to separate hot or cold treatments.

Suppression of established populations of invasive alien species can be a complex and expensive process, which is frequently unsuccessful. The Asian clam, Corbicula fluminea (Müller, 1774), is considered a high impact invader that can adversely alter freshwater ecosystems and decrease their socioeconomic value. To date, C. fluminea continues to spread and persist within freshwater environments worldwide, despite repeated management attempts to prevent dispersal and suppress established populations. As extensive C. fluminea beds can often become exposed during low-water conditions, the direct application of hot or cold thermal shock treatments has been proposed as suitable mechanism for their control. Further, mechanical substrate disturbance may enhance the efficacy of thermal shock treatments by facilitating exposures to multiple layers of buried clams. In the present study, we advanced these methods by assessing combined applications of both hot and cold thermal shock treatments for control of C. fluminea, using steam spray (≥100 °C; 350 kPa), low- or high-intensity open-flame burns (~1000 °C) and dry ice (−78 °C). In a direct comparison of raking combined with hot thermal shock applications, both steam and high-intensity open-flame treatments tended to be most effective, especially following multiple applications. In addition, when hot thermal treatments are followed by a final cold shock (i.e. dry ice), steam treatments tended to be most effective. Further, when dry ice was applied either alone or prior to an application of a hot shock treatment, substantial if not complete C. fluminea mortality was observed. Overall, this study demonstrated that combined applications of hot and cold thermal shock treatments, applied following the disruption of the substrate, can substantially increase C. fluminea mortality compared to separate hot or cold treatments.

Suppression of established populations of invasive alien species can be a complex and expensive process, which is frequently unsuccessful. The Asian clam, Corbicula fluminea (Müller, 1774), is considered a high impact invader that can adversely alter freshwater ecosystems and decrease their socioeconomic value. To date, C. fluminea continues to spread and persist within freshwater environments worldwide, despite repeated management attempts to prevent dispersal and suppress established populations. As extensive C. fluminea beds can often become exposed during low-water conditions, the direct application of hot or cold thermal shock treatments has been proposed as suitable mechanism for their control. Further, mechanical substrate disturbance may enhance the efficacy of thermal shock treatments by facilitating exposures to multiple layers of buried clams. In the present study, we advanced these methods by assessing combined applications of both hot and cold thermal shock treatments for control of C. fluminea, using steam spray (≥100 °C; 350 kPa), low- or high-intensity open-flame burns (~1000 °C) and dry ice (−78 °C). In a direct comparison of raking combined with hot thermal shock applications, both steam and high-intensity open-flame treatments tended to be most effective, especially following multiple applications. In addition, when hot thermal treatments are followed by a final cold shock (i.e. dry ice), steam treatments tended to be most effective. Further, when dry ice was applied either alone or prior to an application of a hot shock treatment, substantial if not complete C. fluminea mortality was observed. Overall, this study demonstrated that combined applications of hot and cold thermal shock treatments, applied following the disruption of the substrate, can substantially increase C. fluminea mortality compared to separate hot or cold treatments.

Since 2016, the European Union (EU) has required Member States to prevent, control and eradicate selected invasive alien species (IAS) designated as Species of Union Concern. To improve these conservation efforts, online information systems are used to convey IAS information to the wider public, often as a means to bolster community-based environmental monitoring. Despite this, both the conformity and quality of information presented amongst online databases remain poorly understood. Here, we assess the harmonisation and educational potential of four major IAS databases (i.e., conformity of information and information quality, respectively): CABI, EASIN, GISD and NOBANIS. All databases were interrogated for information concerning 49 IAS of Union Concern. For each species, information presented within the evaluated databases was scored in relation to several key topics: morphological identification; EU distribution; detrimental impacts; control options; and the use of source material citations. Overall, scores differed significantly among databases and thus lacked harmonisation, whereby CABI ranked significantly highest based on the combined scores for all topics. In addition, CABI ranked highest for the individual topics of species identification, impacts, control options, and for the use of citations. EASIN ranked highest for species distribution data. NOBANIS consistently ranked as the lowest scoring database across all topics. For each topic, the highest scoring databases achieved scores indicative of detailed or highly detailed information, which suggests a high educational potential for the information portrayed. Nevertheless, the extent of harmonisation and quality of information presented amongst online databases should be improved. This is especially pertinent if online databases are to contribute to public participatory monitoring initiatives for IAS detection.

Since 2016, the European Union (EU) has required Member States to prevent, control and eradicate selected invasive alien species (IAS) designated as Species of Union Concern. To improve these conservation efforts, online information systems are used to convey IAS information to the wider public, often as a means to bolster community-based environmental monitoring. Despite this, both the conformity and quality of information presented amongst online databases remain poorly understood. Here, we assess the harmonisation and educational potential of four major IAS databases (i.e., conformity of information and information quality, respectively): CABI, EASIN, GISD and NOBANIS. All databases were interrogated for information concerning 49 IAS of Union Concern. For each species, information presented within the evaluated databases was scored in relation to several key topics: morphological identification; EU distribution; detrimental impacts; control options; and the use of source material citations. Overall, scores differed significantly among databases and thus lacked harmonisation, whereby CABI ranked significantly highest based on the combined scores for all topics. In addition, CABI ranked highest for the individual topics of species identification, impacts, control options, and for the use of citations. EASIN ranked highest for species distribution data. NOBANIS consistently ranked as the lowest scoring database across all topics. For each topic, the highest scoring databases achieved scores indicative of detailed or highly detailed information, which suggests a high educational potential for the information portrayed. Nevertheless, the extent of harmonisation and quality of information presented amongst online databases should be improved. This is especially pertinent if online databases are to contribute to public participatory monitoring initiatives for IAS detection.

Control strategies for established populations of invasive alien species can be costly and complex endeavours, which are frequently unsuccessful. Therefore, rapid-reaction techniques that are capable of maximising efficacy whilst minimising environmental damage are urgently required. The Asian clam (Corbicula fluminea Müller, 1774), and the zebra mussel (Dreissena polymorpha Pallas, 1771), are invaders capable of adversely affecting the functioning and biodiversity of freshwater ecosystems. Despite efforts to implement substantial population-control measures, both species continue to spread and persist within freshwater environments. As bivalve beds often become exposed during low-water conditions, this study examined the efficacy of steam-spray (≥100 °C, 350 kPa) and open-flame burn treatments (~1000 °C) to kill exposed individuals. Direct steam exposure lasting for 5 min caused 100% mortality of C. fluminea buried at a depth of 3 cm. Further, combined rake and thermal shock treatments, whereby the substrate is disturbed between each application of either a steam or open flame, caused 100% mortality of C. fluminea specimens residing within a 4-cm deep substrate patch, following three consecutive treatment applications. However, deeper 8-cm patches and water-saturated substrate reduced maximum bivalve species mortality rates to 77% and 70%, respectively. Finally, 100% of D. polymorpha specimens were killed following exposure to steam and open-flame treatments lasting for 30 s and 5 s, respectively. Overall, our results confirm the efficacy of thermal shock treatments as a potential tool for substantial control of low-water-exposed bivalves. Although promising, our results require validation through upscaling to field application, with consideration of other substrate types, increased substrate depth, greater bivalve densities, non-target and long-term treatment effects.

Since 2016, the European Union (EU) has required Member States to prevent, control and eradicate selected invasive alien species (IAS) designated as Species of Union Concern. To improve these conservation efforts, online information systems are used to convey IAS information to the wider public, often as a means to bolster community-based environmental monitoring. Despite this, both the conformity and quality of information presented amongst online databases remain poorly understood. Here, we assess the harmonisation and educational potential of four major IAS databases (i.e., conformity of information and information quality, respectively): CABI, EASIN, GISD and NOBANIS. All databases were interrogated for information concerning 49 IAS of Union Concern. For each species, information presented within the evaluated databases was scored in relation to several key topics: morphological identification; EU distribution; detrimental impacts; control options; and the use of source material citations. Overall, scores differed significantly among databases and thus lacked harmonisation, whereby CABI ranked significantly highest based on the combined scores for all topics. In addition, CABI ranked highest for the individual topics of species identification, impacts, control options, and for the use of citations. EASIN ranked highest for species distribution data. NOBANIS consistently ranked as the lowest scoring database across all topics. For each topic, the highest scoring databases achieved scores indicative of detailed or highly detailed information, which suggests a high educational potential for the information portrayed. Nevertheless, the extent of harmonisation and quality of information presented amongst online databases should be improved. This is especially pertinent if online databases are to contribute to public participatory monitoring initiatives for IAS detection.

Control strategies for established populations of invasive alien species can be costly and complex endeavours, which are frequently unsuccessful. Therefore, rapid-reaction techniques that are capable of maximising efficacy whilst minimising environmental damage are urgently required. The Asian clam (Corbicula fluminea Müller, 1774), and the zebra mussel (Dreissena polymorpha Pallas, 1771), are invaders capable of adversely affecting the functioning and biodiversity of freshwater ecosystems. Despite efforts to implement substantial population-control measures, both species continue to spread and persist within freshwater environments. As bivalve beds often become exposed during low-water conditions, this study examined the efficacy of steam-spray (≥100 °C, 350 kPa) and open-flame burn treatments (~1000 °C) to kill exposed individuals. Direct steam exposure lasting for 5 min caused 100% mortality of C. fluminea buried at a depth of 3 cm. Further, combined rake and thermal shock treatments, whereby the substrate is disturbed between each application of either a steam or open flame, caused 100% mortality of C. fluminea specimens residing within a 4-cm deep substrate patch, following three consecutive treatment applications. However, deeper 8-cm patches and water-saturated substrate reduced maximum bivalve species mortality rates to 77% and 70%, respectively. Finally, 100% of D. polymorpha specimens were killed following exposure to steam and open-flame treatments lasting for 30 s and 5 s, respectively. Overall, our results confirm the efficacy of thermal shock treatments as a potential tool for substantial control of low-water-exposed bivalves. Although promising, our results require validation through upscaling to field application, with consideration of other substrate types, increased substrate depth, greater bivalve densities, non-target and long-term treatment effects.

Control strategies for established populations of invasive alien species can be costly and complex endeavours, which are frequently unsuccessful. Therefore, rapid-reaction techniques that are capable of maximising efficacy whilst minimising environmental damage are urgently required. The Asian clam (Corbicula fluminea Müller, 1774), and the zebra mussel (Dreissena polymorpha Pallas, 1771), are invaders capable of adversely affecting the functioning and biodiversity of freshwater ecosystems. Despite efforts to implement substantial population-control measures, both species continue to spread and persist within freshwater environments. As bivalve beds often become exposed during low-water conditions, this study examined the efficacy of steam-spray (≥100 °C, 350 kPa) and open-flame burn treatments (~1000 °C) to kill exposed individuals. Direct steam exposure lasting for 5 min caused 100% mortality of C. fluminea buried at a depth of 3 cm. Further, combined rake and thermal shock treatments, whereby the substrate is disturbed between each application of either a steam or open flame, caused 100% mortality of C. fluminea specimens residing within a 4-cm deep substrate patch, following three consecutive treatment applications. However, deeper 8-cm patches and water-saturated substrate reduced maximum bivalve species mortality rates to 77% and 70%, respectively. Finally, 100% of D. polymorpha specimens were killed following exposure to steam and open-flame treatments lasting for 30 s and 5 s, respectively. Overall, our results confirm the efficacy of thermal shock treatments as a potential tool for substantial control of low-water-exposed bivalves. Although promising, our results require validation through upscaling to field application, with consideration of other substrate types, increased substrate depth, greater bivalve densities, non-target and long-term treatment effects.

Invasive alien species (IAS) are a significant and growing problem worldwide. In Europe, some aspects of IAS have been addressed through existing legal instruments, but these are far from sufficient to tackle the problem comprehensively. The FINS II Conference considered the relevance of Top 20 IAS issues (Top 10 threats and opportunities) for Europe determined at the 1st Freshwater Invasiveness – Networking for Strategy (FINS I) conference held in Ireland in 2013. Using a similar format of sequential group voting, threats from FINS I (lack of funding, of awareness and education; poor communication) and several new threats (lack of lead agencies, of standardized management and of common approach; insufficient monitoring and management on private property) were identified by 80 academics, applied scientists, policy makers and stakeholders from 14 EU and three non-EU countries (including 10 invited speakers) during four workshop break-out sessions (legislation remit in both EU/non-EU countries; best management and biosecurity practice for control; data management and early warning; pathways of introductions and citizen science). Identified opportunities include improved cooperation and communication, education and leadership to enhance public awareness and stakeholder participation, systems establishment for early detection, rapid response, monitoring and management of IAS using standardised methods of data collection, storage and usage. The sets of threats and opportunities identified underline the importance of international cooperation on IAS issues in communication, education and funding as priorities, as well as in standardization of legislation, control methods and best practise of research.

Invasive alien species (IAS) are a significant and growing problem worldwide. In Europe, some aspects of IAS have been addressed through existing legal instruments, but these are far from sufficient to tackle the problem comprehensively. The FINS II Conference considered the relevance of Top 20 IAS issues (Top 10 threats and opportunities) for Europe determined at the 1st Freshwater Invasiveness – Networking for Strategy (FINS I) conference held in Ireland in 2013. Using a similar format of sequential group voting, threats from FINS I (lack of funding, of awareness and education; poor communication) and several new threats (lack of lead agencies, of standardized management and of common approach; insufficient monitoring and management on private property) were identified by 80 academics, applied scientists, policy makers and stakeholders from 14 EU and three non-EU countries (including 10 invited speakers) during four workshop break-out sessions (legislation remit in both EU/non-EU countries; best management and biosecurity practice for control; data management and early warning; pathways of introductions and citizen science). Identified opportunities include improved cooperation and communication, education and leadership to enhance public awareness and stakeholder participation, systems establishment for early detection, rapid response, monitoring and management of IAS using standardised methods of data collection, storage and usage. The sets of threats and opportunities identified underline the importance of international cooperation on IAS issues in communication, education and funding as priorities, as well as in standardization of legislation, control methods and best practise of research.

Globally, Invasive Alien Species (IAS) are considered to be one of the major threats to native biodiversity, with the World Conservation Union (IUCN) citing their impacts as ‘immense, insidious, and usually irreversible’. It is estimated that 11% of the c. 12,000 alien species in Europe are invasive, causing environmental, economic and social damage; and it is reasonable to expect that the rate of biological invasions into Europe will increase in the coming years. In order to assess the current position regarding IAS in Europe and to determine the issues that were deemed to be most important or critical regarding these damaging species, the international Freshwater Invasives - Networking for Strategy (FINS) conference was convened in Ireland in April 2013. Delegates from throughout Europe and invited speakers from around the world were brought together for the conference. These comprised academics, applied scientists, policy makers, politicians, practitioners and representative stakeholder groups. A horizon scanning and issue prioritization approach was used by in excess of 100 expert delegates in a workshop setting to elucidate the Top 20 IAS issues in Europe. These issues do not focus solely on freshwater habitats and taxa but relate also to marine and terrestrial situations. The Top 20 issues that resulted represent a tool for IAS management and should also be used to support policy makers as they prepare European IAS legislation.

Globally, Invasive Alien Species (IAS) are considered to be one of the major threats to native biodiversity, with the World Conservation Union (IUCN) citing their impacts as ‘immense, insidious, and usually irreversible’. It is estimated that 11% of the c. 12,000 alien species in Europe are invasive, causing environmental, economic and social damage; and it is reasonable to expect that the rate of biological invasions into Europe will increase in the coming years. In order to assess the current position regarding IAS in Europe and to determine the issues that were deemed to be most important or critical regarding these damaging species, the international Freshwater Invasives - Networking for Strategy (FINS) conference was convened in Ireland in April 2013. Delegates from throughout Europe and invited speakers from around the world were brought together for the conference. These comprised academics, applied scientists, policy makers, politicians, practitioners and representative stakeholder groups. A horizon scanning and issue prioritization approach was used by in excess of 100 expert delegates in a workshop setting to elucidate the Top 20 IAS issues in Europe. These issues do not focus solely on freshwater habitats and taxa but relate also to marine and terrestrial situations. The Top 20 issues that resulted represent a tool for IAS management and should also be used to support policy makers as they prepare European IAS legislation.