Melanoides tuberculata (Müller, 1774) food preference when grazing on

Vaucheria geminata, Melosira varians and Oscillatoria found in Volusia Blue Spring

Shantinique “Kionna” GravesMentor: Dr. Work

http://ts3.mm.bing.net/th?id=H.4929270748479614&w=266&h=181&c=7&rs=1&pid=1.7

Exotic/Invasive species• What is an exotic species?

– Any plant or animal species that has been introduced into an area where they do not naturally occur. Termed: Non-native ("U.S. Fish & Wildlife Service.")

– Invasions of ecosystems by exotic species are increasing, especially in aquatic ecosystems (Byers, 2000)

http://www.aquaesfera.org/atlas/d/5686-4/Melanoides-tuberculata-12.jpg

Exotic/Invasive species• Impact

– Predation – exotic crab prey on native snail (Edgell and Rochette, 2008)

– Competition – invasive snail outcompeted native, aiding in invasion (Byers, 2000)

– Indirect effects – looked at all invasive species as a whole, where you can get total eradication, tolerance, consideration of being a “new” species and overall enrichment to ecosystems: helpful or harmful (Walther, Gian-Reto, et al., 2009) • Nutrient recycling• Selective grazing

Melanoides tuberculata

• Phylum: Mollusca– Class: Gastropoda

• Family: Thiaridae– Genus: Melanoides

• Common names: Red-rimmed melania or Malaysian trumpet snail (aquarium trade)

• Freshwater snail that burrows• Colonizing behavior (mostly asexual and

ovoviviparous) + longevity = successful invasion

https://taxo4254.wikispaces.com/file/view/Features%20of%20snail.jpg/530277828/501x271/Features%20of%20snail.jpg

https://taxo4254.wikispaces.com/file/view/Anatomy%20of%20combined.jpg/529987378/510x331/Anatomy%20of%20combined.jpg

Occurrences• M. tuberculata is originally a native to tropical and subtropical regions

of Africa and Asia (Wingard et al. 2008; Clench, 1969; Neck, 1985). They became exotic through release from the aquarium trade, in which they were imported for in the early 1930’s.

Black = present, Blue = widespread, Red = localized, Green = distributed within a country, Yellow = few reports of being occasionally seenhttps://taxo4254.wikispaces.com/file/view/Global%20distribution%20of%20MT.jpg/530325582/616x332/Global%20distribution%20of%20MT.jpg

http://nas2.er.usgs.gov/viewer/GetStaticMap.aspx?region=us&width=700&height=450&layer=na%20gl%20bnds%20sts%20rivers%20shuc6%20shuc8%20snativehuc%20maptitle%20logo%20legend%20copy&maptitle=Melanoides%20tuberculata%20&speciesid=1037

It was first spotted in the United States in Arizona in the 1950's (Murray, 1971; Dundee, 1974). They are very successful in Florida and Texas (Benson and Neilson, 2014).

Purpose

• Impact of exotic species– Predation– Competition– Indirect effects

• Nutrient recycling• Selective grazing

Volusia Blue Spring State Park• M. tuberculata likes to live

in areas humans inhabit• Prefer areas that have

slow or stagnant flow• Cause for concern:

– Exotic– Host for parasitic flukes

(liver and lung)– Effect on the biological

landscape (ecosystem)

Volusia Blue Spring algal bloomshttps://encrypted-tbn0.gstatic.com/images?

q=tbn:ANd9GcTjuInHokHTHDY20q-GJoOS9i7xSWjIcPrdfOBB2sqigpHjreT8LA

https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRqCBXiSZhvR4XbMPukyH6n2hWo4eDk7weRkBvRlvIYBHAJaFML

http://www.landcareresearch.co.nz/__data/assets/image/0019/62272/melosira3.jpg

https://microscopesandmonsters.files.wordpress.com/2013/09/browney_melosira_1.jpg

http://pages.vassar.edu/viva/files/2013/08/IMG_6156.jpg

http://oceandatacenter.ucsc.edu/PhytoGallery/images_AM/Freshwater/oscillatoria3.jpg

Grazing• It is an aquatic herbivorous snail that feeds

on benthic and epiphytic algae– Mainly eat algae, such as microalgae

(diatoms)– Can also eat detritus and organic particles that

are deposited on the sediments (detritivore) (Subda Rao and Mitra, 1982)

– Generalist?

Hypothesis• Does M. tuberculata have a

food preference for one of the dominant algae found in Volusia Blue Springs State Park?

• We hypothesized that M. tuberculata would have a food preference for Vaucheria geminata.

Methods

Statistical analysis• One-way ANOVA with Tukey multiple

comparisons to compare algal weight loss between treatments

Results• M. tuberculata had a food preference

– for Vaucheria geminata

Figure 1. Overall average algae wet weight loss after the experiment Snails: p < 0.0001, Algae: p < 0.0001, Interaction: p =0.033

Does preference change with type of algae present?

• We wanted to know if placement mattered among the algae

• With and without snails

Figure 2. Vaucheria algal wet weights compared to Melosira and Oscillatoria with and without snails.

P = 0.541 Not Statistically Significant

Figure 3. Melosira algal wet weights compared to Vaucheria and Oscillatoria with and without snails

P < 0.0001 Statistically Significant

Figure 4. Oscillatoria algal wet weights compared to Vaucheria and Melosira with and without snails

P < 0.24 Not Statistically Significant

Discussion• Does M. tuberculata have a food

preference for one of the algae found in Volusia Blue Springs State Park?– Supported

• Interesting finding:– Placement in treatments was important

Discussion Cont.• Placement was important

– Vaucheria was the most eaten and placement did not matter

– Oscillatoria was the least eaten and placement did not matter

– However, placement mattered when it came to Melosira• More Melosira was consumed when

Oscillatoria was present than Vaucheria

Future research• Do they eat other types of algae?• Growth on different types of algae• Patterns of algal growth and proximity

of Melanoides to different taxa• Competition?• Larger sample size

Acknowledgements• Stetson Biology Department• Dr. Work• Friends & Family• Blue Spring State Park

Work cited

Benson, A.J., and M.E. Neilson. (2014) Melanoides tuberculata. USGS Nonindigenous Aquatic Spesies Database, Gainesville, Fl. http://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=1037 Revision Date: 2/28/2013 (Accessed 14 March 2014)

Byers, J.E. (2000) Competition between Two Estuarine Snails: Implications for Invasions of Exotic Species. Ecology 81(5): 1225-1239

Clench, W.J. (1969) Melanoides tuberculata (Muller) in Florida. Nautilus 83: 72Dundee, D.S., (1974) Catalog of introduced mollusks of eastern North America (north of Mexico). Sterkiana 55: 1-37Edgell, T.C. and Rochette, R. (2008) Differential snail predation by an exotic crab and the geography of shell-claw covariance in

the Northwest Atlantic. Evolution 62(5): 1216-1228Murray, H.D., (1971) The introduction and spread of thiarids in the Unites States. The Biologist 53(3): 133-135Neck, R.W. (1985) Melanoides tuberculata in extreme southern Texas. Texas Conchologist 21(4): 150-152"U.S. Fish & Wildlife Service." FAQs. N.p., n.d. Web. 06 Apr. 2015.Walther, Gian-Reto, et al. (2009) "Alien species in a warmer world: risks and opportunities." Trends in ecology & evolution

24(12): 686-693.Wingard, G.L., Murray, J.B., Schill, W.B., Phillips, E.C. (2008) "Red-Rimmed Melania (Melanoides tuberculatus) - A Snail in

Biscayne National Park, Florida - Harmful Invader or Just a Nuisance?" USGS United States Geological Survey http://pubs.usgs.gov/fs/2008/3006/pdf/fs2008-3006.pdf (Accessed 13 February 2014)

Questions?