November 13, 2023 — Prey animals often grapple with the challenge of finding secure breeding sites, but how they make those decisions is uncovered in a new research paper by Hebrew University of Jerusalem (HU) researchers.

The study led by Dr. Viraj Torsekar and Prof. Dror Hawlena, ecologists from the Hebrew University Department of Ecology, Evolution, and Behavior, delves into the intricate dynamics of burrow-site selection amidst looming predators, like scorpions. Published in the journal Biology Letters, it focused on desert Isopods (woodlice) (up to two centimeters long) in Israel’s Negev Desert, which are vital components of ecosystems, and contribute to the decomposition of organic matter.

This study aimed to investigate whether prey animals lean toward safer breeding sites over riskier ones when presented with a choice. It also explored how the preference for safety might differ among individuals with varying competitive abilities, especially when the costs of competing within their species outweigh the benefits of securing a safer breeding site.

“Our findings suggest that the landscape of fear, shaped by the presence of predators, influences the behavior of prey animals in intricate ways,” says Dr. Viraj Torsekar. “It’s not solely about safety; it’s about carefully weighing the costs and benefits of every decision, even when it pertains to fundamental choices like selecting a breeding site.”

The study found that larger females are more likely to occupy burrows than smaller females, regardless of whether these burrows were near or far from scorpion burrows. The researchers also found that larger females stayed longer in safer burrows and that smaller females tended to stay longer in riskier sites even in the absence of direct competition, implying a prudent burrow-site selection.

The study paves the way for a deeper understanding of the intricate ecological interactions between predators and prey, underscoring the significance of examining the subtleties of animal behavior within the delicate balance of nature.