Field foot patrols effectiveness for wildlife protection in a large vegetal mosaic Kafue National Park (22,400 km2) was assessed for two successive periods of different duration. The relationship between patrol days spent in the field by patrol teams and resultant outcomes was determined. Using trained patrol scout teams, field data was recorded on prescribed patrol forms. Prosecution data was populated into database and analysed for their spatial coverage. Study findings showed that 2 to 8 day foot patrols were more effective than protracted patrols. By changing field patrol duration the Wildlife Agency significantly reduced events of “serious and minor offences” and saved at least 46.67% of its conservation funds for foot patrols. Most of the offenders (69.13%) of environmental crimes originated from adjacent areas to the Park. It was proposed that wildlife managers explore and implement effective pragmatic foot patrols on site specific basis. In addition, it was postulated that community based conservation programmes in peripherals of Kafue National Park, if strengthened, could greatly contribute to biodiversity conservation. Future studies would be required to further investigate drivers of environmental crimes, elucidating attitudes of poachers and reasons for their involvement in illegal wildlife trade vis-a-vis local demands of natural products. Key words: Environmental crimes, effectiveness, community based conservation, Kafue National Park, Zambia.