Premium
Density Effects on the Survival, Growth Rate, and Metamorphosis of Rana Tigrina Tadpoles
Author(s) -
Dash Madhab C.,
Hota Ashok K.
Publication year - 1980
Publication title -
ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.144
H-Index - 294
eISSN - 1939-9170
pISSN - 0012-9658
DOI - 10.2307/1936818
Subject(s) - metamorphosis , biology , larva , population density , density dependence , bufo , population , ecology , zoology , growth rate , competition (biology) , tadpole (physics) , toad , demography , physics , particle physics , geometry , mathematics , sociology
Rana tigrina larvae were reared in isolation, at various densities and controlled food levels, and with Bufo melanostictus larvae in laboratory populations. Growth is sigmoid in isolated individuals and mass reaches a maximum just before metamorphosis. In laboratory populations, survival during the larval period was independent of initial population density, but the proportion of the population that successfully completed metamorphosis was a negative exponential function of density. This is interpreted as the result of the slower growth rate in high—density populations arising from the competition for food. The individuals in high—density populations with slower growth rate take a longer time to reach a threshold size and have a lower probability of completing metamorphosis. In higher densities, the threshold size for metamorphosis decreases in comparison to lower density populations.