The importance of understanding altitudinal variation in biodiversity protection has witness less patronage in sub–Sahara Africa. The physiognomy of Okwangwo Range, Cross River National Park, Nigeria is highly variable; rich in plants and animals. This study evaluates the influence of altitudinal variation on wildlife with focus on avifauna. Three distinct elevation zones were delineated: low, mid and high elevation. Time–species count method was used in obtaining data on bird species. The study employed analysis of variance (ANOVA) to analyze the differences in bird richness along the low, mid high altitudes. Result obtained show that the calculated–F value (10.19) is greater than the critical–F value (3.35) at 0.05 significant levels. This implies that there is a significant difference in bird species richness along the altitudinal zones of the study area.  The observed percentage representation of exclusiveness of bird species richness along the altitudes in the study area was in the following order: exclusive to low altitude only, 3.33 per cent; exclusive to mid altitude only, 5.24 per cent; and exclusive to high altitude only, 36.19 per cent. Also, exclusive to  both high and mid altitudes only, 9.05 per cent; exclusive to both mid and low altitudes only, 25.24 per cent; exclusive to both high and low altitudes, 0.95 per cent; and exclusive to high, mid, and low altitudes together, 20 00 per cent. This suggests important conservation implication: the entire range need equal conservation attention.