Data for: Beyond simple habituation: Anthropogenic habitats influence the escape behavior of spur-winged lapwings in response to both human and non-human threats
Cite this dataset
Bar-Ziv, Michael; Sofer, Aran; Gorovoy, Adel; Spiegel, Orr (2022). Data for: Beyond simple habituation: Anthropogenic habitats influence the escape behavior of spur-winged lapwings in response to both human and non-human threats [Dataset]. Dryad. https://doi.org/10.5061/dryad.ns1rn8px7
Habitat development may affect wildlife behavior, favoring individuals or behaviors that cope better with perceived threats (predators). Bolder behaviors in human-dominated habitats (HDH; e.g., urban and rural settlements) may represent habituation specifically to humans, or a general reduction in predator-avoidance response. However, such carry-over effects across threat types (i.e., beyond humans) and phases of the escape sequence have not been well studied to date. Here we investigated escape behaviors of a locally common wader species, the spur-winged lapwing (Vanellus spinosus). We assayed their flight initiation distance (FID) and subsequent escape behaviors in agricultural areas and in HDH. We found that lapwings in HDH were bolder, and that the difference was manifested in several phases of the predator-avoidance sequence (shorter FIDs, shorter distances fled, and a higher probability of escape by running vs. flying). When re-approached (by an observer) after landing, lapwings in HDH were also more repetitive in their FID than those in other habitats. To determine whether this apparent bolder behavior in HDH areas is merely a consequence of habituation to humans or represents a broader behavioral change, we introduced an additional threat type – a remotely-operated taxidermic jackal (“Jack-Truck”). Finding bolder responses in the HDH to the human threat alone (and not to the Jack-Truck) could have supported the habituation hypothesis. In contrast, however, we found a bolder response in the HDH to both threat types, as well as a correlation between their FIDs across different sites. These bolder behaviors suggest that HDH impose a broader behavioral change on lapwings, rather than just simple habituation. Overall, our findings demonstrate how FID trials can reveal strong behavioral carry-over effects of HDH following human and non-human threats, including effects on the subsequent phases of escaping the predator. Further, FID assays may reveal consistent behavioral types when assessed under field conditions, and offer a direct way to differentiate among the various poorly understood and non-mutually exclusive mechanisms that lead to behavioral differences among organisms in HDH. The mechanistic perspective is essential for understanding how rapid urbanization impacts wildlife behavior, populations, and the range of behaviors within them, even in species apparently resilient to such environmental changes.
Research approach: Our approach was based on initiating escape behavior via an FID (flight initiation distance) approach, using either a human observer or a simulated jackal as the potential threat. We used binoculars (Nikon monarch 5, 10x42), to search for a candidate Spur-winged lapwings (*Vanellus spinosus*). Only calm individuals were tested, starting ~30-100 meters from the bird, depending on local conditions. We compared three habitats and tested the whole sequences of escape behaviors performed by the focal bird in response to simulated threats.
The human threat was always simulated by the same observer (MBZ, lead author), similarly dressed, approaching the bird at a regular and continuous walking speed (~1 m/s). A second observer remained in a hidden area (a car in our case) to assist with data collection. These trials took place between February 2019 to March 2020.
The non-human threat was a taxidermic juvenile jackal (height ~40 cm) mounted on top of a camouflaged remotely controlled vehicle with off-road ability (Traxxas summit 56076-4, 50x30 cm, "Jack-Truck"). The trial employed the same protocol as described above, but with both observers remaining behind, to minimize their impact. We conducted Jack-Truck trials in all three habitat types. Trials were done during November 2019 to March 2020.
If the focal bird, following its initial escape, landed within a reachable point we performed a second FID of the same threat type immediately after the first one.
We used a laser rangefinder (Nikon Aculon 6x20) for all distance measurements (in meters, ensuring accuracy through three consecutive measurements) and corrected using triangular compass calculation for the Jack-Truck location in the relevant trials. Data was collected within Epicollect5.
All models were constructed with the "lme4" package in R environment (Bates et al. 2014; RStudio Team 2020).
Repeatability was tested with a Gaussian distribution in the rptR package in R environment (Stoffel et al. 2017).
Israel Science Foundation, Award: 396\20