Despite her commitments in France with Eurasian lynx, Marine has finally found some time to publish her research on black-backed jackal and caracal diet through the investigation of GPS location clusters that she compared with scat analysis. The article was published in the Journal of Zoology. She found that the GPS location cluster technique was suitable to study caracal diet on Karoo farmland but that it was not detecting the small prey components in jackal diet. So it’s better to collect and analyze scats as well if the goal is to get a full image of what jackals eat in this region. A finding that farmers know already was that both jackals and caracals on farms were found to kill livestock and not simply to scavenge on it. Interestingly though, that was not the case of jackals living in Anysberg Nature Reserve, even when those jackals explored the surrounding farmland! Anysberg jackals were not killing livestock when they left the protected area. We are not sure why it is the case but we hypothesized that these jackals might not readily consider livestock as a prey species. We know from a previous study we conducted on their diet through scat analysis that jackals eat a lot of small rodents and berries in Anysberg Nature Reserve (see that study here). Once they are on neighboring farmland, they might look for these same types of prey to feed on rather than for sheep. They also do not spend a lot of time on farmland. More research would need to be conducted to validate or invalidate this hypothesis though, and to study how long it would take for jackals to start eating sheep on those farms if they were staying there for a longer time. Regarding caracals on farmland, we found that adult males were preying more on livestock than young individuals or females.
Here is the abstract of the paper:
Studying the feeding ecology of mesopredators living on or adjacent to farmland is important as livestock predation fuels conflict between farmers and predators and between diverse stakeholders on how to best manage this conflict. Most dietary studies on elusive and heavily persecuted predators rely on indirect methods such as scat analysis, because direct observations of predation events are rare. Consequently, the proportion of livestock and other prey that was actively hunted vs. scavenged remains largely unknown. We used data from global positioning system collars affixed to black‐backed jackal (Canis mesomelas) and caracal (Caracal caracal) to locate potential feeding sites on farmland and a protected area and to attempt to determine whether prey had been killed or scavenged. We compared dietary estimates from prey items found at global positioning system location clusters (GLCs) with those obtained from scat analysis and investigated whether GLC analysis is a suitable method to determine mesocarnivore diet. The success rate of finding a kill site when investigating GLCs was significantly higher for caracal than for jackal. Only 16.2% and 4.7% of jackal and caracal GLCs, respectively, were classified as scavenging events. Livestock was the most frequently detected prey in both scats and GLCs on farmland but GLCs provided a higher estimate of sheep biomass than scats. Caracal GLCs revealed prey ranging in size from small to large, whereas jackal GLCs were only for medium and large prey categories. Adult male caracals predated significantly more on livestock than females and younger individuals. Collared jackals residing in the protected area never formed GLCs containing livestock remains on neighbouring farms. Together, GLCs and scat analyses provide a more complete understanding of mesopredators feeding ecology on farmland. We recommend that both methods are applied, particularly in regions where livestock predation and lethal management of predators are driving conflict between stakeholders.