Semen production of the American kestrel

Abstract

In 1975, semen was collected by massage from 18 randomly selected captive male American kestrels (Falco sparverius). The period of semen production extended for 103 days, beginning on March 19, while the mean duration of semen production was 73.6 days. Under natural light, semen production began at [Formula: see text] of daily light, peaked about [Formula: see text], and decline considerably around June 21 at [Formula: see text]. Weather factors, i.e., temperature, barometric pressure, did not significantly (P > 0.05) affect semen collections or quality.The following means were calculated: semen volume, 12 μl; sperm concentration, 31 000/mm3; sperm count per ejaculate, 416 000; motility score, 78%; contamination with epithelial debris and urates, 67%; and semen colour, very pale to pale amber.The following significant (P < 0.05) correlations were found: body weight with semen volume (0.48) and sperm count per ejaculate (0.54); egg fertility with sperm count per ejaculate (0.65); semen volume with sperm count per ejaculate (0.84) and sperm motility (0.54); sperm count per ejaculate with sperm concentration (0.78); and sperm motility with sperm concentration (0.59) and sperm count per ejaculate (0.75).