Deer Yard Lake is managed for Walleye, and has historically supported high numbers of small, slow-growing Walleye. Walleye were still abundant in 2013. Although the 2013 gill net catch was the lowest ever observed for Deer Yard Lake it still exceeded the normal range for similar lakes in the state. The mean weight of Walleye sampled in 2013 was low for the this lake type, but was about average for the lake historically. Walleye growth had been slow; fish attained a length of just 8.7 in at the end of their third year compared to a mean of 10.3 in for similar lakes in the Grand Marais area. The slow growth of Walleye in Deer Yard Lake can be attributed to the lack of high-quality forage within the system, and competition for macroinvertebrates from a dense White Sucker population. However, Deer Yard Lake may have the potential to produce an occassional trophy Walleye as was seen in the 2013 assessment.
White Sucker also remained abundant in Deer Yard Lake in 2013. Most of the White Sucker collected in 2013 were too large to serve as forage for any but the largest Walleye in the lake. A few Golden Shiners were sampled in 2013, in small-mesh trap nets. Deer Yard Lake is also known to support small numbers of Creek Chub and Brook Stickleback.