This study aimed to verify the effectiveness of rescue apparatus, that can capture crabs using external stimuli such as food and electricity, without relying on divers. In this study, a microcomputer-based controller and an IC-device-based controller were developed, and spot inspection was conducted using 20 modules and 30 sea urchin removal modules. Accordingly, 58, 18, 17, and 74 sea urchins were introduced in the first, second, third and fourth experiments, respectively. The result of evaluating the lure of each removal mechanism, based on the catch per unit effort, with an electrical stimulus was 1.1 (32/10), with a feeding stimulus was 3.4 (100/29), and with electrical and feeding stimuli was 3.5 (35/10).