Dingle H. & Khamala C.P.M. (1972) Seasonal changes in insect abundance and biomass in an east African grassland with reference to breeding and migration birds. ARDEA 60 (3-4): 216-221

1) Sweep samples were taken of the insect fauna of the Athi Plains grasslands near Nairobi, Kenya. Samples were taken during both wet seasons and both dry seasons. 2) Some increase in insect numbers and a large increase in insect biomass occurred at the time of the 'long rains' in April-May. These data support Owen's contention that major fluctuations in insect faunas occur near the equator in East Africa. 3) It is not possible to ascertain whether fluctuations in insect numbers or biomass are in fact used as cues to trigger bird migration, but they are probably large enough to be so used. 4) Most savannah and dry country birds breed during the long rains; this breeding is correlated with a major increase in the availability of insect food.