Foraging Effects of the Invasive Alien Fish Pterygoplichthys on Eggs and First-Feeding Fry of the Native Clarias macrocephalus in Thailand

ABSTRACT Native to Latin America, the sailfi n armored catfi sh Pterygoplichthys has been introduced to Thailand for the ornamental fi sh industry. This invasive species has fl ourished in nature and may threaten aquatic resources, especially of indigenous freshwater fi sh due to its foraging activities. This study investigated the biological impacts of the sailfi n armored catfi sh on the eggs and the fi rst-feeding fry of the Thai native catfi sh, Clarias macrocephalus that are found in similar habitats. The results showed that small, medium and large Pterygoplichthys fed on up to 95% or more of native catfi sh eggs within 24 hr. Pterygoplichthys also consumed the fi rst-feeding fry of C. macrocephalus. The average consumption of fi rst-feeding fry by small, medium and large Pterygoplichthys was 26.3±7.2, 71.8±23.5 and 86.3±13.7%, respectively. These results clearly indicated that the consumption of the catfi sh eggs was much higher than for the fi rst-feeding fry primarily due to the fact that the eggs were immobile and accessible. In addition, the consumption rates of fi rst-feeding fry by the armored catfi sh were positively correlated with the size of Pterygoplichthys (correlation coeffi cient = 0.6238, P < 0.01). In conclusion, Pterygoplichthys can destroy the eggs and fi rst-feeding fry of the native catfi sh Clarias macrocephalus and has the potential to reduce the populations of Thai native fi sh species

A global-scale screening of non-native aquatic organisms to identify potentially invasive species under current and future climate conditions

The threat posed by invasive non-native species worldwide requires a global approach to identify which introduced species are likely to pose an elevated risk of impact to native species and ecosystems. To inform policy, stakeholders and management decisions on global threats to aquatic ecosystems, 195 assessors representing 120 risk assessment areas across all six inhabited continents screened 819 non-native species from 15 groups of aquatic organisms (freshwater, brackish, marine plants and animals) using the Aquatic Species Invasiveness Screening Kit. This multi-lingual decision-support tool for the risk screening of aquatic organisms provides assessors with risk scores for a species under current and future climate change conditions that, following a statistically based calibration, permits the accurate classification of species into high-, medium-and low-risk categories under current and predicted climate conditions. The 1730 screenings undertaken encompassed wide geographical areas (regions, political entities, parts thereof, water bodies, river basins, lake drainage basins, and marine regions), which permitted thresholds to be identified for almost all aquatic organismal groups screened as well as for tropical, temperate and continental climate classes, and for tropical and temperate marine ecoregions. In total, 33 species were identified as posing a 'very high risk' of being or becoming invasive, and the scores of several of these species under current climate increased under future climate conditions, primarily due to their wide thermal tolerances. The risk thresholds determined for taxonomic groups and climate zones provide a basis against which area-specific or climate-based calibrated thresholds may be interpreted. In turn, the risk rankings help decision-makers identify which species require an immediate 'rapid' management action (e.g. eradication, control) to avoid or mitigate adverse impacts, which require a full risk assessment, and which are to be restricted or banned with regard to importation and/or sale as ornamental or aquarium/fishery enhancement. Decision support tools AS-ISK Hazard identification Non-native species Risk analysis Climate changepublishedVersio

A global-scale screening of non-native aquatic organisms to identify potentially invasive species under current and future climate conditions

The threat posed by invasive non-native species worldwide requires a global approach to identify which introduced species are likely to pose an elevated risk of impact to native species and ecosystems. To inform policy, stakeholders and management decisions on global threats to aquatic ecosystems, 195 assessors representing 120 risk assessment areas across all six inhabited continents screened 819 non-native species from 15 groups of aquatic organisms (freshwater, brackish, marine plants and animals) using the Aquatic Species Invasiveness Screening Kit. This multi-lingual decision-support tool for the risk screening of aquatic organisms provides assessors with risk scores for a species under current and future climate change conditions that, following a statistically based calibration, permits the accurate classification of species into high-, medium- and low-risk categories under current and predicted climate conditions. The 1730 screenings undertaken encompassed wide geographical areas (regions, political entities, parts thereof, water bodies, river basins, lake drainage basins, and marine regions), which permitted thresholds to be identified for almost all aquatic organismal groups screened as well as for tropical, temperate and continental climate classes, and for tropical and temperate marine ecoregions. In total, 33 species were identified as posing a ‘very high risk’ of being or becoming invasive, and the scores of several of these species under current climate increased under future climate conditions, primarily due to their wide thermal tolerances. The risk thresholds determined for taxonomic groups and climate zones provide a basis against which area-specific or climate-based calibrated thresholds may be interpreted. In turn, the risk rankings help decision-makers identify which species require an immediate ‘rapid’ management action (e.g. eradication, control) to avoid or mitigate adverse impacts, which require a full risk assessment, and which are to be restricted or banned with regard to importation and/or sale as ornamental or aquarium/fishery enhancement.publishedVersio

Birds and the eutrophication of a system of small lakes

Brown Moss is a Site of Special Scientific Interest and a part of a RAMSAR site located within a small catchment area in North Shropshire. Despite its small size, it is important and has ostensibly high ecological values. It comprises a series of standing water bodies that are crucial natural habitats for rare aquatic plants and animals such as Luronium natans (Linnaeus) and Triturus cristatus (Laurenti). However, located within such small catchment area, Brown Moss may have been eutrophicated by nutrients from land use and other factors around the site and this can lead to reduction of importance and ecological values. Being waterfowl habitats, the pools may also have become affected by nutrient input from birds and aquatic macrophytes communities may have been damaged.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Measuring sustainability performance of rice cultivation in Thailand using Sustainable Rice Platform indicators

The sustainability level of current rice farming practices in Thailand was assessed based on in-field data from interviewing 2000 farmers covering six rice varieties and their different production systems. Data were collected on farmers’ characteristics and farming activities according to the 41 requirements of the Sustainable Rice Platform (SRP) standard. The SRP scores ranged from 53 to 81%, with the best performance by Khao Dawk Mali 105 cultivated in rainfed, organic production systems. The key success factors were linked to the formation of a farmer group resulting in very good performance on farm management, Integrated Pest Management, health and safety, and water use. The proposed 12 performance indicators (PIs) interconnected with the 41 requirements are considered appropriate to measure and monitor progress toward sustainable rice cultivation for policy makers. PIs for good governance, affordability of living costs, energy-use efficiency, and life satisfaction could potentially be added, considering the local context in relation to sustainable agriculture goals. The successful cases of SRP-certified rice farms and the benefits from SRP implementation should be conveyed to with other rice farmers to induce wider implementation. The SRP scores and PIs were useful to identify areas requiring priority interventions to make progress toward sustainability

Speaking their language – Development of a multilingual decision-support tool for communicating invasive species risks to decision makers and stakeholdersolders

Environmental changes due to non-native species introductions and translocations are a global concern. Whilst understanding the causes of bioinvasions is important, there is need for decision-support tools that facilitate effective communication of the potential risks of invasive non-native species to stakeholders. Decision-support tools have been developed mostly in English language only, which increases linguistic uncertainty associated with risk assessments undertaken by assessors not of English mother tongue and who need to communicate outcomes to local stakeholders. To reduce language-based uncertainty, the ‘ecology-of-language’ paradigm was applied when developing the Aquatic Species Invasiveness Screening Kit (AS-ISK), a decision-support tool that offers 32 languages in which to carry out screenings and communicate outcomes to stakeholders. Topics discussed include uncertainty related to language-specific issues encountered during the AS-ISK translation and the potential benefits of a multilingual decision-support tool for reducing linguistic uncertainty and enhancing communication between scientists, environmental managers, and policy and decision makers

Development and application of a multilingual electronic decision-support tool for risk screening non-native terrestrial animals under current and future climate conditions

Electronic decision-support tools are becoming an essential component of government strategies to tackle non-native species invasions. This study describes the development and application of a multilingual electronic decision-support tool for screening terrestrial animals under current and future climate conditions: the Terrestrial Animal Species Invasiveness Screening Kit (TAS-ISK). As an adaptation of the widely employed Aquatic Species Invasiveness Screening Kit (AS-ISK), the TAS-ISK question template inherits from the original Weed Risk Assessment (WRA) and related WRA-type toolkits and complies with the ‘minimum requirements’ for use with the recent European Regulation on invasive alien species of concern. The TAS-ISK consists of 49 basic questions on the species’ biogeographical/historical traits and its biological/ecological interactions, and of 6 additional questions to predict how climate change is likely to influence the risks of introduction, establishment, dispersal and impact of the screened species. Following a description of the main features of this decision-support tool as a turnkey software application and of its graphical user interface with support for 32 languages, sample screenings are provided in different risk assessment areas for one representative species of each of the main taxonomic groups of terrestrial animals supported by the toolkit: mammals, birds, reptiles, amphibians, annelids, insects, molluscs, nematodes, and platyhelminths. The highest-scoring species were the red earthworm Lumbricus rubellus for the Aegean region of Turkey and the New Zealand flatworm Arthurdendyus triangulatus for Croatia. It is anticipated that adoption of this toolkit will mirror that of the worldwide employed AS-ISK, hence allowing to share information and inform decisions for the prevention of entry and/or dispersal of (high-risk) non-native terrestrial animal species – a crucial step to implement early-stage control and eradication measures as part of rapid-response strategies to counteract biological invasions