Summary
Objective: Problems related to feral pigeons (Columba livia) in cities mainly result from their large numbers due to uncontrolled population
growth. The aim of this study was to evaluate whether endoscopic guided sterilization
affects the reproductive behavior of feral pigeons under experimental conditions,
with the intention of assessing this technique as a potential method for feral pigeon
population control. Materials and methods: Five groups of four pairs of feral pigeons each were studied from 8 weeks before,
to 7 weeks after sterilization. Both the male and female of the first pair of each
group were steri lized, in the second pair only the female and in the third pair only
the male was sterilized. The fourth pair acted as a control. All eggs laid were candled
to assess fertility. Results: Surgical sterilization had minimal effects on behavior and therefore seems not to
have impact on possible field application for population control. All pairs maintained
their pair bonds and continued to defend their nesting sites against other pigeons.
Only one female copulated with a foreign fertile male while her primary partner was
debilitated due to surgery, but returned to him as soon as he recovered. All eggs
laid more than 5 days after male sterilization were infertile, whereas all control
pairs had fertile eggs. Only one fertile clutch was produced, 5 days after the male’s
sterilization. Therefore it is assumed that males remain fertile for a limited period
of time. Conclusion: Endoscopic sterilization seems to be a promising method for field control of feral
pigeon populations and sterilization of the male only seems sufficient.
Keywords
Feral pigeons - reproductive behavior - endoscopic sterilization - population control
