Web updates are intermittent, not continuous, therefore some dynamic information such as legal status may not be absolutely current. Thayer's gulls are found near water. Direct mortality risk from zinc phosphide is low. However, damage may occur to kidney, lungs and liver. This is based on a physiological study done using Siberian ferrets.
Zinc phosphide is highly to extremely toxic to both mammals and birds.
All scavengers are at risk of primary poisoning and possibly secondary poisoning from zinc phosphide in meat baits. Hubbard, J.P. 1978. Revised checklist of the birds of New Mexico. 10 American Ornithology Union. Supplement to the Auk.