Apple snails

Pomacea spp.


  • A genus of freshwater snail inhabiting marshes, swamps, ditches, irrigation canals, ponds, and lakes
  • Prefers water bodies lined with vegetation and with muddy bottoms
  • It can tolerate polluted waters with low oxygen levels
  • Pomacea canaliculata and Pomacea maculata are the most documented Pomacea species
  • It is difficult to differentiate between Pomacea species without DNA analysis
  • Apple snails have a thin, smooth, globose shell, growing 3-8cm in diameter
  • Shell colour varies from yellow-brown to dark chestnut with some having dark spiral bands
  • Shell whorls are rounded, with deep channels between them
  • The snail has four tentacles with only two long and one short tentacle visible
  • It has a long extendable siphon on the left side for surface breathing
  • Fully grown females are larger than males
  • Egg masses are laid just above the waterline on plant material, logs, walls, or rocks
  • Masses can contain more than 1000 brightly coloured eggs that get lighter as they are about to hatch
  • Eggs hatch after 2 weeks, with hatchling shells around 2mm in diameter
  • After 45 days, juveniles become fully grown and can reproduce
  • During dry periods it can survive in the soil for more than 5 months, until water is present
Origin and Worldwide Distribution
  • Native to South and Central America, including the Caribbean
  • One species is native to Florida, USA
  • Introduced across Southeast and east Asia, the USA, and the Ebro Delta in Spain
  • Sold as pets through the aquarium trade in Northern Ireland, Great Britain and Ireland.
Potential or Known Impacts
  • Considered one of the most invasive invertebrates of waterways and irrigation systems
  • They have a broad diet, consuming large amounts of aquatic vegetation, altering ecosystems
  • Loss of vegetation increases water nutrient concentrations, phytoplankton biomass and water turbidity
  • They can reduce native snail biodiversity through predation and competition
  • Act as a vector for parasites that can cause human diseases
Is it found in Northern Ireland?
  • It is not currently present in Northern Ireland
How could it get here?
  • Introductions would most likely be a result of the deliberate or accidental release of individuals kept illegally in aquariums
Management/Methods for Prevention
  • Prevention via enforcing the Plant Health (Official Controls and Miscellaneous Provisions) Regulations (Northern Ireland) 2020 ensuring that the genus Pomacea is not introduced to Northern Ireland
  • Reporting any sightings so that Rapid Response can be instigated
Current Legislative Position
  • The genus Pomacea is listed on the list of Union quarantine pests
  • It is illegal to have them on sale in Northern Ireland, whereas they are not illegal to sell in Great Britain
  • This requires extra vigilance on aquarium products being shipped from G.B. to N.I.
  • Under the Plant Health (Official Controls and Miscellaneous Provisions) Regulations (Northern Ireland) 2020 it is an offence to introduce or cause the spread of the genus Pomacea
For further queries, you can contact the Invasive Non Native Species (INNS) Team in the Northern Ireland Environment Agency on 028 9056 9558 or Email:  
An article published by CABI in August 2022 - The life cycle of the golden apple snail  
Invasive Species Northern Ireland

Invasive Species Northern Ireland