Objetivos. Establecer la presencia y prevalencia de parásitos nematodos Strongylida en Achatina fulica en el Valle del Cauca, especialmente los nematodos que son potencialmente patogénicos para los humanos. Materiales y métodos. Individuos de A. fulica fueron colectados en nueve ciudades del Valle del Cauca, Colombia. Los nematodos fueron identificados mediante inspección directa de los individuos, estos se separaron de los tejidos y el mucus, luego, los nematodos se lavaron en solución salina, y fijaron en solución AFA caliente. Se montaron placas en glicerina para observar al microscopio. Resultados. La prevalencia general de parásitos nematodos fue 35% en 2013. La ciudad con mayor prevalencia durante 2013 fue Cartago (60%), seguido de Buenaventura (42.9%) y Cali (33%), mientras que en 2014 fue Cali (30%) y Buenaventura (30%). Los nematodos Strongylida registrados fueron clasificados en tres géneros: Angiostrongylus (prevalencia 14.7%), Aelurostrongylus (2.6%), y Strongyluris (2.6%). La ciudad con la mayor cantidad de positivos para Angiostrongylus fue Cali durante 2014 y Buenaventura con Aelurostorngylus para el 2013. El género Strongyluris solo se reportó en Cali durante 2013, con una prevalencia del 11%. En cinco de las nueves ciudades evaluadas se registró la presencia de Angiostrongylus. Conclusiones. Tres géneros de nematodos Strongylida se reportaron en individuos de A. fulica en el Valle del Cauca durante 2013 y 2014. Por lo tanto, no debe subestimarse el papel de A. fulica y las especies de moluscos nativas en el ciclo de vida de estos parásitos.

The Giant African Snail (Lissachatina fulica) is one of the 100 world’s worst invasive species and has been recorded in the Neotropical region since the 1980s. Temperature and precipitation variables affect snail population density; however, these relationships have not been investigated for L. fulica on a regional scale. Here, we made the first description of variation in population density of L. fulica in the Neotropical region using a literature search, descriptive statistics, and a Principal Component Analysis (PCA). We found 22 studies covering 36 localities in six countries. The mean snail density was 11.55 ± 28.32 ind/m2, with the lowest value recorded in Cuba (0.0002 ind/m2) and the highest value recorded in Venezuela (150 ind/m2). These values were recorded between 21 % to 93 % of Human Footprint, 710 mm to 4438 mm of Annual Precipitation, 13 ºC to 27 ºC, Mean Temperature of the Coldest Quarter, and 3 ºC to 40 ºC of Temperature Seasonality. The PCA suggested that low densities can occur in various environmental conditions, whereas medium and high densities seem to appear in more specific climatic combinations. In conclusion, increased densities of Lissachatina fulica in the Neotropics seem to be influenced by climatic variations, especially the Mean Temperature of the Coldest Quarter and Annual Precipitation, supporting previous findings in the literature regarding the snail establishment. Future monitoring of this invasive species, performed at expanded spatial and temporal scales, may provide tools to establish a relationship between snail density values and impact.

The morphological characterisation of populations of exotic species is relevant for monitoring their impacts, as morphological traits are the first to react to environmental gradients. In Colombia, the giant African snail (Achatina fulica) has expanded across the country, occupying different habitats. We assessed the morphological variations of its shell in the cis- and trans-Andean regions of Colombia. We systematically and opportunistically collected snails at 12 locations in Colombia and applied geometric morphometric methods to analyse shell morphology variations. We found significant differences in A. fulica shell morphology, size, and allometry between cis- and trans-Andean regions. We also found differences in the frequencies of colour patterns, with pattern #2 being most frequent in the cis-Andean region and pattern #5 in the trans-Andean region. Results suggest that the shell morphology of A. fulica is an attribute that may respond to environmental, management or genetic differences between cis- and trans-Andean regions and that these differences should be considered in the design of management strategies across the country.

In Colombia, the control of giant African snail populations (Achatina fulica) has been enforced for the past eight years according to the Environmental, Housing, and Territorial Development Ministry (MAVDT from its initials in Spanish). During this period, the environmental authorities have carried out a series of campaigns for snail eradication and to raise awareness in the general community to involve it in the control of this invasive species. In order to inquire about the perception of the citizens of Cali, Colombia, have of the giant African snail and their role as primary stakeholders in the local control programs, a structured survey was done, and the dependency on the sociodemographic characteristics was established through Fisher’s exact test. 316 people took part in the survey; over 80% of the individuals recognized the giant African snail and their form of control, but over 90% of them did not participate in the control campaigns. The perception of the giant African snail varied noticeably with the respondents’ age and was independent of socio-economic and educational level. In conclusion, it was detected a solid dissociation between people and the actions carried out by the environmental authority. It is recommended to take into account people’s concept of invasive species control in other cities as a fundamental instrument in the construction of a more dynamic and inclusive control model.