1NPS Alaska Regional Office, Alaska SeaGrant; firstname.lastname@example.org
2NPS Skagway National Historic Park; email@example.com
3NPS Skagway National Historic Park; firstname.lastname@example.org
In late April of 2017 gulls, bald eagles, and harbor seals, and a few intrepid scientists congregated near the outlet of the Taiya River. Located near Skagway Alaska, the Taiya River flows from the Coastal Mountains, through Klondike Gold Rush National Historical Park (hereafter Klondike Gold Rush), and into a large estuary delta near the former Gold Rush town of Dyea. On this mild spring day, humans and wildlife alike were eagerly awaiting the same natural phenomenon- the arrival of a small, silvery, unassuming fish known by many names.
Sometimes called hooligan or candlefish, but most often referred to as Eulachon (Figure 1), Thaleichthys pacificus, is an anadromous smelt. These fish grow and feed in the cold waters of the North Pacific before returning to rivers in late winter or early spring to reproduce. Much like salmon, Eulachon are fundamentally semelparous, or reproduce once and die shortly thereafter (Clarke et al. 2007). Iteroparous (spawn more than once) individuals exist in some populations at unknown frequencies (Willson et al. 2016). Adult Eulachon generally spawn at 2-5 years old (Willson et. al. 2006). While spawning is reported to take place at a wide range of temperatures 0oC -10oC in different river systems, with run timing occurring in earlier in warm years (Willson et al. 2006), raising concern about predicted changes in river temperatures.