We develop an averaging method, based on a modified Haar wavelet technique, for identifying when transient features occur in a time signal. We call this method the seaweed method and use it to identify different stages of bean beetle embryo maturation. We use randomized simulations to evaluate the seaweed method for accuracy and precision at different levels of noise. Our results support the efficacy of the seaweed method as a means for analyzing time-lapse photographs of bean beetle embryos and a wide variety of other time signals.