COOPERATIVE ENDEAVOR ASSESSES APPLE SNAIL POPULATION ON PRIVATE LAND NORTH OF HOUMA

Release Date: 04/22/2008



The Louisiana Department of Wildlife and Fisheries (LDWF) and the Barataria-Terrebonne National Estuary Program (BTNEP) teamed up April 22 to remove apple snails and assess the level of infestation on a landowner's property a few miles west of Shriever.


Apple snails are an invasive aquatic species from South America.  They were first discovered in Louisiana in 2006 near Gretna and have since been found in several water bodies within the Barataria-Terrebonne Estuary. 


Apple snails cause damage to the marshes and swamps by out-competing native species for resources because of their large size, and the ability to quickly populate.  They consume large quantities of plant material, which damages native fish and other aquatic organisms habitats.  They are also an invasive species to Southeast Asia, and have become a major source of crop damage to rice farmers there.


Shriever resident and fisherman Douglas Rhodes first reported seeing the apple snail last winter.  The snails' presence was confirmed by Michael Massimi, the BTNEP's Invasive Species Coordinator in late January of this year.  "The apple snail could pose a real threat to the ecological balance of the Barataria-Terrebonne Estuary System," said Massimi.  "As the potential impacts are largely unknown, it is important to act quickly."


LDWF Aquatic Nuisance Species Coordinator Brac Salyers said, "Because of how fast this species could take hold, and the fact that we don't know the size of the problem we have right now, we'd rather act quickly than wait.  This effort is half removal and half finding out the size of this population.  If we find a lot more here than we think, we'll have to start immediately planning a much bigger removal."


Apple snails were most likely introduced into Louisiana through aquarium owner releases.  They have also been found in Florida and Texas.  They are among the largest freshwater snails with golden-yellow to dark brown shells and range from 2 to 4 inches across, with the largest one reaching 6 inches in diameter. 


Most people will only see their bright pink egg clusters of 200 to 600 eggs attached to trees or other structures just above the waterline.  Egg masses can simply be scraped off the structures and allowed to fall into the water where they become inundated with water and become infertile.


"The public can help us a lot by reporting any infestations they see, or removing the eggs themselves and dropping them in the water," said Salyers.  "The biggest problem with the aquarium trade business is that in most cases they don't inform the public of the potential problem of releasing these non-native species in the wild.  Properly disposing of non-native aquarium life forms would help prevent the spread of snails, fish and plants into Louisiana waterways."


If consumed raw, apple snails can possibly transmit many diseases, including a deadly parasite called rat lungworm, to humans and other mammals.  However, there is no risk of illness from touching egg masses or the shell, but gloves or other protective equipment should be used when removing the egg masses.



For more information, contact LDWF Aquatic Nuisance Species Coordinator Brac Salyers at 225-765-2641 or bsalyers@wlf.louisiana.gov;
or Contact BTNEP Invasive Species Coordinator Michael Massimi at 985-449-4714.


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