Disclaimer:

The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.

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Common name: titan applesnail

Taxonomy: available through www.itis.gov

Identification: Large globular shaped shell.

Native Range: South America (Bolivia, Brazil, and Peru)

Alaska	Hawaii	Puerto Rico & Virgin Islands	Guam Saipan

Hydrologic Unit Codes (HUCs) Explained
Interactive maps: Point Distribution Maps

Ecology: Freshwater rivers.

Means of Introduction: Probable aquarium introduction.

Status: This is the only known area where this species is established in the United States (Rawlings et al. 2007).

Impact of Introduction: The impacts of this species are currently unknown, as no studies have been done to determine how it has affected ecosystems in the invaded range. The absence of data does not equate to lack of effects. It does, however, mean that research is required to evaluate effects before conclusions can be made.

Remarks: Research by Savaya-Alkalay et al. (2018) suggests that the development of all-male prawn populations of Macrobrachium rosenbergii has the potential as an biocontrol agent over hatchling and adult apple snails (Pomacea spp.). Medium-sized and large prawns (10–30 g) efficiently preyed on snails up to 15mm in size, while small prawns (up to 4 g) effectively consumed snail hatchlings.

References: (click for full references)

Rawlings, T. A., K. A. Hayes, R. H. Cowie, and T. M. Collins. 2007. The identity, distribution, and impacts on non-native apple snails in the continental United States. BMC Evolutionary Biology, http://www.biomedcentral.com/1471-2148/7/97.

Savaya-Alkalay, A., Ovadia, O., Barki, A., and A. Sagi. 2018. Size-selective predation by all-male prawns: implications for sustainable biocontrol of snail invasions. Biological Invasions 20:137–149.

Other Resources:
US Fish and Wildlife Service Ecological Risk Screening Summary for Pomacea haustrum

Author: Benson, A.J.

This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.