Old Tom (c. 1860s/1895 – September 1930) was a male orca (killer whale) who cooperated with and assisted whalers in the port of Eden, New South Wales, on the southeast coast of Australia.

Old Tom was believed to be the leader of a pod of orcas which helped the whalers by herding baleen whales into Twofold Bay.

[5] Old Tom measured 22 feet (6.7 m) and weighed 12,000 pounds (6 tons), with a 3.33 ft (1.01 m) skull and teeth about 5.31 inches (135 mm) long.

[6] They relied on traditional whaling techniques, such as row boats and hand harpoons, that did not disturb or put stress on the orcas with loud noise,[7] while also reducing operating costs.

[8] Eden, first established in 1842, is located 470 km (290 mi) south of Sydney in the greater area of Twofold Bay.

[6] This bond might have been established due to the whalers of the crew feeding Old Tom and other orcas fish while waiting for passing whales.

[7] The law of tongue dates back to indigenous Australian history, similarly to the food offering to the beowas by locals for generations.

[16] According to Davidson family history, Old Tom was known to them for 80 years and was present for the baleen whale migration seasons from the 1860s until his death in September 1930.

The Davidson family described Tom as an "athletic and skillful whale hunter", who would commonly be seen towing smaller fishing boats by their anchor line.

[6] Old Tom and his pod returned every winter during the migration seasons of baleen whales, from late May until early September.

[6] While the exact number of orcas in the pod is unknown, 21 were known by name, identified by their differences in dorsal fins:[6] Stranger, Jackson, Hooky, Humpy, Cooper, Typee, Big Ben, Young Ben, Kinscher, Jimmy, Sharkey, Charlie Adgery, Brierly, Albert, Youngster, Walker, Big Jack, Little Jack, Skinner, and Montague.

[6] Orcas utilize distraction shading and countershading as camouflage, as their distinctly contrasting and sharp edged markings visually break up their outlines making it difficult for panicked prey to easily determine their direction and orientation.

[15] The return of Old Tom alone to Twofold Bay has been interpreted as him returning to familiarity after losing the rest of his pod: locals believe the rest of Old Tom's pod was killed further north in Jervis bay by Norwegian whalers, unaware of the relationship between these orcas and the whalers.

[6] Additionally, a study published in October 2023 by Isabella Reeves et al., of Old Tom's genome and comparisons of his DNA to other orcas across the world suggests that neither Old Tom nor any of his pod left any confirmed descendants, suggesting that Eden's orcas were rendered locally extinct.

[20][21] Old Tom was found dead on 17 September 1930 by George Davidson in the southern part of Twofold Bay.

[9] Old Tom's fascination with mooring lines and towing boats into the open ocean, reflected by the half-circular pattern on his teeth, is documented in the Eden Killer Whale Museum.

Scientists determined that orca teeth naturally wear down over the span of their lifetime, resulting in exposed pulp cavities and abscesses.

[24][18] Filmmaker George McKee produced an ABC documentary, "Killers in Eden", in 2004 based on the story of the Davidsons, Old Tom and his pod.