Tigertail Glacier begins at an elevation of about 2,850 feet (869 m) in the Sargent Icefield on the Kenai Peninsula and flows generally northeast for 3.3 miles (5.3 km), terminating 0.2 miles (0.3 km) from the western shore of Nassau Fjord, a northern arm of Icy Bay in western Prince William Sound, about 36 miles (58 km) east-northeast of Seward and 36 miles (58 km) south-southeast of Whittier, Alaska. Named in 1909 by George W. Perkins, it takes its name from the larger Tiger Glacier about 3 miles (4.8 km) to the southwest. Nassau Fjord is about 4 miles (6.5 km) long and includes the Chenega Glacier, which terminates at tidewater, and the Princeton and Tigertail glaciers, which terminate on shore. The bedrock exposed by the retreating glaciers is part of one of the world’s largest accretionary complexes, the Southern Margin composite terrane, formed by several component groups. The rocks surrounding Prince William Sound belong to the Valdez Group, which developed during the Late Cretaceous (about 100 million to 66 million years ago) and the Orca Group, which developed from the late Paleocene to the middle Eocene (about 60 to 40 million years ago). Separated by the Johnstone Bay Fault—roughly aligned with the axis of Icy Bay—the Valdez Group lies to the west and the Orca Group to the east. Both comprise similar sedimentary rocks: mostly graywacke sandstone, siltstone, mudstone, slate, and some conglomerate. Structures such as graded bedding, crossbedding, and ripple marks, along with flute, groove, and load casts, indicate deposition by turbidity currents.

The first account of glaciers in Icy Bay dates to 1789, when Nathaniel Portlock visited Prince William Sound. Though fog prevented him from seeing the glacier front, he encountered large amounts of drift ice and heard the distant rumbling of calving ice. The first visual description came in 1794, when Lieutenant Joseph Whidbey, on the Vancouver Expedition, mapped the ice front across Icy Bay near the entrance to Nassau Fjord. Samuel Applegate‘s explorations aboard the private schooner Nellie Juan in 1887 brought the western coast of Prince William Sound into sharper focus; though he never published his narrative, George Davidson studied and summarized it, producing the earliest map referencing many of the sound’s glaciers. An 1898 army expedition led by Captain Edwin F. Glenn found the glacier in Icy Bay in roughly the same position as Whidbey had recorded. In 1908 Ulysses S. Grant and Daniel F. Higgins navigated 10 miles (16 km) into the bay and noted separate ice streams in Nassau Fjord. The following year, George W. Perkins—a wealthy industrialist and partner of J.P. Morgan—leased the SS Yucatan, a flagship of the Alaska Steamship Company, to bring 18 family members to Alaska to view the Guggenheim family‘s holdings. His party named and photographed the Princeton, Nassau, and Tigertail glaciers, as well as Nassau Fjord. In 1910 Ralph S. Tarr and Lawrence Martin, on a National Geographic Society-funded expedition, found the ice fronts unchanged from the previous year and studied vegetation in Icy Bay, finding trees 24 to 32 inches (61–81 cm) in diameter with annual rings indicating ages of 110 to 120 years.

Tigertail Glacier lies in the northwestern part of Nassau Fjord, about 0.5 miles (0.8 km) south of the Chenega Glacier terminus. During the most recent major ice advance in southern Alaska, roughly 10,000 years ago, many glaciers reached their maximum extent. A minor advance began around 1300 AD, when the Princeton Glacier merged with the Chenega and Tigertail glaciers and advanced to the mouth of Nassau Fjord. Core samples extracted in 1957 from trees beyond the terminal moraine at the fjord’s mouth indicated the ice front had not exceeded that position since at least 1675 AD. The coalesced Princeton-Chenega-Tigertail ice front held at the mouth of Nassau Fjord until roughly 1857–82. Between 1898 and 1908, the Chenega Glacier retreated more than 2 miles (3.2 km), reopening Nassau Fjord and separating the glaciers into individual ice streams. Since 1908, Tigertail Glacier has lost volume and retreated from tidewater. A small glacier covering 1,728 acres (700 ha), it is confined between the narrow walls of a steep valley; its terminus is now relatively stable and has receded less than 330 feet (100 m) since 1908. Read more here and here. Explore more of Tigertail Glacier and Nassau Fjord here: