During the week of October 20^th employees from the Columbia National Fish and Wildlife Conservation Office (NFWCO) refocused their efforts from pallid sturgeon to lake trout. Cliff Wilson, Joe McMullen, and Chris McLeland left the Missouri River behind to assist with lake trout spawning efforts at Sullivan Creek National Fish Hatchery, in Brimley, Mich. The hatchery is located only a few miles off the coast of Lake Superior. It is one of a few lake trout rearing facilities in the region. The facility holds approximately 25,000 lake trout of varying size classes and this year alone produced roughly 6.8 million eggs. The lake trout from this and previous years spawns were produced for stocking in all of the great lakes as well as some lakes in Canada were the species naturally occurred.

When we arrived at the hatchery the staff had been spawning lake trout for a while but still had hundreds waiting to spawn. When spawning begins in the fall it all occurs during a short period of time, so it is all hands on deck at the hatchery. We were given a short orientation on how to assist with the spawning, then we jumped right in with the staff.

The lake trout were sedated and the ripe (ready to spawn) females and males were separated. The females were squeezed to collect their bright orange eggs. After the eggs were collected in plastic trays the males were squeezed above the trays to fertilize the eggs with their milt. The fertilized eggs were then placed in a hatchery room where they are presently developing to produce lake trout for future stockings.

Lake trout are a native species to many lakes in the northern U.S. and Canada. They are a deep water, predatory species, which during the 1950’s was severely diminished due to over harvest. Today they struggle with parasites such as the exotic sea lamprey. The U.S. Fish and Wildlife Service maintains several lake trout hatcheries involved in producing fish to restore this species’ numbers in the wild. There are also many studies in progress dedicated to better understanding and protecting this species. This work meets the U.S. Fish and Wildlife Services’ objective of restoring declining native fish populations. 

Joe McMullen, Cliff Wilson, and Chris McLeland