An evaluation of chemical and physical defenses against fish predation in a suite of seagrass-associated ascidians

►We evaluated the palatability of five species of ascidians. ►Two solitary and one colonial ascidian species were unpalatable to fish. ►Organic extracts of the three unpalatable species did not cause feeding deterrence. ►Inorganic acids were not found to be deterrent to the fish. ►Tunic toughness may explain unpalatability of solitary species.