It was almost midnight and there was still plenty of sunlight; we were cold, wet and happy at the same time because we were at Walker Lake, a glacier-formed lake in the Arctic. While the float plane was approaching to the lake, the view was astonishing. The water was completely transparent in the shallows and a change to intense blue reflected the abrupt increase in depth at the end of the shelf. At first sight, it seemed a fishless lake due to the lack of activity at the surface, contradicting what we had read before about the lake fauna. Soon, our lures and flies showed the magic of the Arctic: lake trout were taking lures and flies of all sizes and colors, confirming the nonexistent fishing pressure in the lake.
Lake trout were large and beautiful with pale spots covering the body. The large mouth extending past margin of the eye was striking, which intimates the voracity of this char. To our surprise, the one trout whose stomach contents we examined had been eating terrestrial insects. This was a surprise because lake trout are best known as deep water predators on fish and shrimp. After leaving the lake, we continued to catch lake trout. The variability of the stomach contents (from aquatic macroinvertebrates, terrestrial ants, and voles) confirmed its omnivorous feeding habits and ravenous appetite. The trout were surprisingly abundant in the river, especially upstream from the confluence with the Pah River. Lake trout generally inhabit cold and deep lakes and complete their life cycle in lentic habitats; for example, this occurs in the well-studied populations of Lake Superior. I wonder if fish found in the Kobuk River conduct large spawning migrations in the fall to deep lakes, such as Walker Lake and Lake Selby; or perhaps they behave like stream resident fish and spawn and overwinter in deep pools that do not freeze solid during the harsh arctic winters. We observed that the stream lake trout had orange fins while the lake fish fins were pale.
Anyhow, it appeared that lake trout were thriving with healthy populations both in Walker Lake and in the Kobuk River.
