Mollusca Archives - Eva Varga


September 27, 20134

Prior to our departure for holiday in China, we had enjoyed the new DreamWorks movie, Turbo. Snails were thereby on our mind and to the delight of the kiddos, we happened upon a few small garden variety in the ancient gardens of China and at the Panda Breeding Center in Chengdu.  In Yangshuo, we discovered what the locals called Duck Snails, a large freshwater snail belonging to the family Ampullariidae.  The more accepted common name is the Apple Snail, an aquatic gastropod mollusks with gills and an operculum.

apple snails

Field Studies

We first noted the presence of these snails because of the bright pink egg masses that we observed all over the shoreline of the Yu Long (Dragon) River. These egg masses are laid on solid surfaces up to about 20 inches above the water surface. An average clutch contains 200 to 600 eggs, with each egg measuring 0.9 to 1.4 mm in diameter. Soon thereafter, as the kids began to play in the river, we found adult snails in a variety of hues, ranging from creamy yellow to a light pink.

As amateur naturalists, we are not sure exactly what species we observed (Pomacea canaliculata or Pomacea insularum) – perhaps even multiple species.  Based upon our research, we are leaning towards P. canaliculata.  Even so, the kids enjoyed playing with them and watching them glide across the surface of the bamboo boat structure that was anchored near shore.

Sweetie expressed wanting to take them home and of course, I explained that this was not only illegal (customs would certainly not allow us to transport live animals back to the states) but it would also be negligent on our part and potentially environmentally catastrophic.

applesnails

Phylum Mollusca

When we returned home, I took advantage of their interest in the snails, to engage them in a little nature journaling.  I pulled out a few text books and had the photographs we had taken in Yangshuo available on the iPad.  Sweetie ran to her room and brought back one of the shells she had collected during our stay.  We then got about sketching and noting our observations in our journals.

As they worked, I read aloud a book that I had purchased years ago in Hawai’i, Beyond ‘Ohi’a Valley: Adventures in a Hawaiian Rainforest by Lisa Matsumoto.   The illustrations are very beautiful and the characters are very comical; the storyline tells about the native animals of Hawai’i and the impact of invasive, non-native species.  While discuss how similar problems could occur with the introduction of the apple snail – in fact, it is happening …

Pomacea canaliculata is native to temperate Argentina and northwards to the Amazon basin. Through human introduction, this applesnail has rapidly spread to Indonesia, Thailand, Cambodia, Hong Kong, southern China, Japan, Philippines, and Hawai’i. There are indications that they are invading Australia. In the 1980’s, channeled applesnails were introduced in Taiwan to start an escargot industry. This snail was originally imported under the name “golden snail” or “golden applesnail” for human consumption. However, the Asian escargot market never materialized and applesnails, that escaped or were released, ultimately came to cause extensive damage to rice fields. 

I’ve posted more pictures and information about Pomacea canaliculata onto Project Noah.  I encourage you to hop over if you are interested in learning more about Apple Snails.

Submitted to the Outdoor Hour Challenge Blog Carnival at Handbook of Nature Study.