Dr. Jessica Schackermann, Academic Director of the Arava Institute, recently co-published a paper in the academic journal Diversity on “The Contribution of Desert-Dwelling Bats to Pest Control in Hyper-Arid Date Agriculture.”
Agricultural produce is a major source of income in the southern Arava region, with dates being one of the primary crops produced. On date plantations, night-active moths are among the main threats to crop production. While pesticides do exist for the treatment of many insect pests, farmers are required to cease pesticide application at least 80 days prior to harvest, leaving dates vulnerable in the interim. According to Dr. Schackermann, crop loss from insect pests in the post-spraying period can be substantial. In addition, farmers report that some insect pests demonstrate resistance to certain pesticides.
In her latest research, Dr. Schackermann, who also has academic affiliations with Southern Arava R&D, sought to explore whether bats, whose natural diet consists entirely of insects, might serve as natural pest-control agents. Dr. Schackermann tested whether some of the 16 total bat species present in the region use date plantations for foraging, and whether they might be “persuaded” to do so more intensively by making date plantations more hospitable for them.
Dr. Schackermann and her colleagues recorded bat activity in data plantations across the southern Arava Valley and collected feces for DNA analysis to determine the presence of pest species in the bats’ diet. They found that 12 of the 16 species frequently used both conventional and organic date plantations as habitats for foraging, feeding on a variety of important date pests. To Schackermann, this points to a “win-win situation,” where bats provide bio-pest control services that benefit farmers, while at the same time the plantations serve as a supportive home for bats, whose populations are dwindling worldwide.
Some bats eat their body weight in insect pests on a nightly basis, so the benefit to farmers can be quite significant. In order to attract bats, farmers must ensure that their plantations are suitable on two key parameters, Dr. Schackermann noted. First, bats need water. In fact, the very first thing bats do when they wake up each night (bats are nocturnal) is drink. However, bats drink in flight (i.e. they don’t stop on the ground to drink), so it is important that the water source be unimpeded in at least two opposite directions, like a landing strip. The second way that plantations can be optimized for bat habitation is by providing a suitable roost. Schackermann believes that the bats found in the plantations mostly roosted in nearby caves, since bats prefer spacious accommodations that are cooler than the ambient temperature. If date farmers provide suitably spacious and insulated bat houses on premises, something Schackermann is working on as the next phase of her research, she surmised that even more bats would frequent the plantations.
