The splake (Salvelinus namaycush X Salvelinus fontinalis) is a hybrid of two fish species resulting from the crossing of a male brook trout (Salvelinus fontinalis) and a female lake trout (Salvelinus namaycush). The name itself is a portmanteau of speckled trout (another name for brook trout) and lake trout, and may have been used to describe such hybrids as early as the 1880s. Hybrids of the male lake trout with the female brook trout (the so-called "brookinaw") have also been produced, but are not as successful.
The intrageneric hybrid is of the genus Salvelinus and, hence, is most properly known as a char or charr. In some locales, the fish is referred to as the wendigo. Although the hybrid is genetically stable and is, theoretically, capable of reproducing, splake reproduction is extremely rare, for behavioural reasons, outside the hatchery environment. The only known natural reproduction has occurred in five lakes in Algonquin Provincial Park in Ontario, Canada and, in each case, only a handful of progeny were produced. Because splake typically do not reproduce, they are used as a sport fish in many lakes across the US. Fisheries managers are able to control populations numbers due to the extremely poor spawning success rate.
The fish possess characteristics of both parent species. Splake exhibit higher growth rates than either parent species and can attain 46 cm (18 in) in length only two years after being planted as fingerlings (i.e., at 2½ years of age). By way of contrast, lacustrine brook trout would approach 25 cm (10 in) in length at a similar age and similarly aged lake trout would be expected to be less than 40 cm (16 in) long.
Splake are considered "easier to catch" than other salmonids and often live longer and fare better in certain situations. Hence, splake are well suited for stocking in a variety of coldwater lakes and ponds. The maximum size is about 9 kg (20 lb), but fish over 4 kg (9 lb) are rare and are considered trophies.