Using camera traps to study the age–sex structure and behaviour of crop-using elephants Loxodonta africana in Udzungwa Mountains National Park, Tanzania

Abstract

26Crop losses from elephants are one of the primary obstacles to the coexistence of 27 elephants and people and one of the contributing causes to elephant population 28 decline. Understanding if some individuals in an elephant population are more likely 29 to forage on crops, and the temporal patterns of elephant visits to farms, is key to 30 mitigating the negative impacts of elephants on farmers. We used camera traps as a 31 novel technique to study elephant crop foraging behaviour in farmland adjacent to 32 the Udzungwa Mountains National Park in southern Tanzania from October 2010 to 33 August 2014. Camera traps placed on elephant trails into farmland captured 34 elephants on 336 occasions over the four-year study period. We successfully 35 identified individual elephants from camera trap images for 126 of these occasions. 36All individuals detected on the camera traps were independent males, and we 37 identified 48 unique bulls aged between 10 and 29 years. Two-thirds of the bulls 38 identified were detected only once by camera traps over the study period, a pattern 39 that also held during the last year of study when camera trapping effort was 40 continuous. Our findings are consistent with previous studies that found that adult 41 males are more likely to adopt high-risk feeding behaviours such as crop foraging, 42 though young males dispersing from maternal family units also consume crops in 43 Udzungwa. Our study found a large number of occasional crop-users (32 of the 48 44 bulls identified) and a smaller number of repeat crop-users (16 out of 48), suggesting 45 that lethal elimination of crop-using elephants is unlikely to be an effective long-term 46 strategy for reducing crop losses from elephants. 47 48

All-Male Groups in Asian Elephants: A Novel, Adaptive Social Strategy in Increasingly Anthropogenic Landscapes of Southern India

“…4). Information on elephant age, sex, group size, group composition and musth state was collected and individual identification carried out, simultaneously across these locations using photographs obtained 48–51 . These cameras covered a gradient of forest fragmentation and human use within the study area (Srinivasaiah N.M., Sinha, A., Vaidyanathan, S. & Sukumar, R. unpublished data) and were operational both during the day and at night, ensuring spatio-temporal coverage.…”

Using very high-resolution satellite imagery and deep learning to detect and count African elephants in heterogeneous landscapes

“…Censuses can be carried out without concern for human safety providing an ability to survey previously inaccessible areas. For example, in the case of the Emperor penguin, new colony locations were detected in a pan-continental survey of the Antarctic coast [7,13]. Additionally, cross border areas can be surveyed without requiring multiple national civil aviation permissions.…”

“…Various methods are used for conducting population counts e.g. line transect surveys [4], dung and track counts [5], bio-acoustic monitoring [6], camera trap [7] and aerial surveys [8], among others.…”

Using camera traps and digital video to investigate the impact of Aethina tumida pest on honey bee (Apis mellifera adansonii) reproduction and ability to keep away elephants (Loxodonta africana cyclotis) in Gamba, Gabon

“…As interspecies interactions are not easy to visually observe and study especially in the forested tropical environment, camera traps and digital video (CT&DV) might prove useful in such contexts especially with regard to elephants (Chaiyarat et al, 2015;Ngama et al, 2016;Smit et al, 2017;Ngama et al, 2018). That is why we decided to use these devices to study bees (Apis mellifera adansonii (Latreille, 1804)) and forest elephants (Loxodonta africana cyclotis Matschie 1900) interactions.…”