I don't know where that name came from, Elaine. Perhaps the "namer" (is that a word?) had never seen an elk horn............
The picture is not a very good one, but those fronds are wavy and forked, but not as forked as the staghorn and they don't fork until the fronds grow large.
Since I have hundreds of tropical plants (how about 500+
) and am watering and fertilizing all the time, my staghorn and elkhorn ferns get fertilized along with the rest. I am using diluted fertilizer though, no more than 1/2 strength (weakly - weekly). I don't fertilize them in the fall or winter months.