Life history parameters as indicators of growth rate in three salp populations

A strong correlation exists between individual growth rate andfive life history parameters in the fast growing salp Thaliademocratica. The five parameters are number of aggregate budsper chain; body size of reproductive solitaries; the ratio ofaggregate offspring to their solitary parents; the solitaryto aggregate ratio; and the relative proportions of juvenilesand adults in the solitary generation. Correlation coefficientsaveraging 0.68 and ranging up to 0.85 were found between theestimates of these parameters in 37 samples of salp blooms takenover 15 years in the western Pacific and eastern Indian oceans.Growth rate, estimated previously in 12 of these samples, alsocorrelated strongly with each of the five parameters with coefficientsranging from 0.88 to 0.96. After analysis of partial correlationswe selected parameters to form regression equations with growth.These equations are excellent indicators of growth in the sequentiallysampled salp populations. Because of the significant correlationbetween the parameters in a wider range of samples, they arealso likely to be indicators of growth in general salp populations.