Meeting Abstract
P3.123 Monday, Jan. 6 15:30 Comparative Performance of an Endemic Oahu snail (Auriculella sp.) in Native versus NonNative Host Plants HOWARD, C.A.K*; HOLLAND, B.S.; University of Hawaii at Manoa; University of Hawaii at Manoa cierrah@hawaii.edu
Although Hawaiian snails generally occur only on native plants, a single population has been observed in nonnative ginger and jasmine. We tested laboratory performance (survival and reproduction) on different plant species for an endemic Hawaiian snail, in 3 phases, each run for a period of 3 months. In Phase I, groups of 10 Auriculella sp. were placed in five cages. In two (native cages) we placed native plants, ohia (Metrosideros polymorpha) and i’e i’e (Freycinetia arborea), while the other two treatment cages (nonnative cages) contained nonnative plants white ginger (Hedychium coronarium) and jasmine (Cestrum nocturnum). A fifth cage was set as a control with both native and nonnative plants plus cultured leaf fungus. Cages were regularly cleaned, vegetation replaced, and eggs counted. To compare reproduction and survival of juveniles from different host plants, eggs were collected, and incubated at two different temperatures. Incubation time, hatch rate, and survival of juveniles from native versus nonnative cages were recorded. In Phase II, host plant composition of native and nonnative cages was reversed, to account for variation in fecundity. In Phase III we tested performance on different individual host plants by separation into four cages, each with a single host plant (ohia, i’e i’e, ginger, or jasmine). We then tested for statistically significant differences among treatments. Preliminary results suggest that snails in native cages produced about 20 times more eggs than those in nonnative cages, innate variation in fecundity did not account for differential reproductive output observed, and jasmine is a superior host plant than ginger. Our results have implications for conservation of rare Hawaiian snails, including captive propagation strategies.
