Joseph Richard Slevin (September 13, 1881 – February 17, 1957) was an American herpetologist and the second curator of herpetology at the California Academy of Sciences, with which he was affiliated for over 50 years.

The purpose of the voyage was to study the geology of the islands as well as collect plants, mollusks, insects, birds, mammals, and reptiles, and, as Van Denburgh wrote, "to spare no effort to secure specimens or remains of those races of the gigantic land tortoises which long had been thought extinct.

Biologists Thomas and Patricia Fritts, who later edited and published Slevin's field notes, write that although he was "first and foremost a collector of reptiles, he was also a conscientious naturalist who recorded observations in a manner uncharacteristic of the times.

[2][6] Biologist Vasco M. Tanner writes Slevin was largely responsible for collecting and preserving the more than 75,000 specimens housed in the academy by the time of his death.

[6] During World War I, Slevin served as a submarine commander in the Navy, and in 1928 succeeded Van Denbourgh as curator of academy herpetology collections.