Camera traps reveal elephant crop-use behaviour in Udzungwa Mountains National Park, Tanzania
What is it about?
We used camera traps placed on elephant trails from forest to farms to study the age-sex structure and behaviour of crop using elephants near Udzungwa Mountains National Park, Tanzania. We identified 48 unique bulls aged 10-29 years over the four-year study period. Our study provides further evidence of a male bias in crop use, as well as variability among males in the frequency of crop use. Similar to a previous study in Amboseli, Kenya (Chiyo et al. 2011), we find that a large number of bulls are likely to be occasional crop-users, and a smaller number are likely to be repeat users. As in Kibale, Uganda (Chiyo & Cochrane 2005) and Amboseli, Kenya (Chiyo et al. 2011), we find that older, reproductive bulls are more likely to engage in repeat crop-use. As in Kibale but not Amboseli, we find that some crop-users are young bulls of dispersing age.
Why is it important?
Our study has implications for methods used to mitigate crop losses to elephants. Given the large number of crop-users in a small area of farmland, most of whom were occasional crop users, lethal control of crop-using elephants is costly and unlikely to be an effective long-term strategy for reducing crop losses. Lethal control also carries other risks, such as misidentifying individuals and eliminating older, reproductive males. We also show that camera trapping is a useful tool for studying crop-use behaviour, and is complementary to other methods such as crop-loss enumeration.