# Integrating Indoor Hibernation into the Italian Outdoor Snail Farming System: A Potential Solution for Colder Climates

## TL;DR

This study explores using indoor hibernation in Italian snail farming to improve survival in colder climates.

## Contribution

The study adapts indoor hibernation practices to the Italian outdoor snail farming system to reduce winter mortality.

## Key findings

- Micro shelters reduced labor time for snail collection compared to hand-picking.
- Indoor hibernation with proper insulation improved survival rates compared to poorly insulated spaces.
- Most snail deaths were due to environmental factors, not predation.

## Abstract

Farms operating under the Italian outdoor snail farming (IOSF) system use the Mediterranean snail Cornu aspersum as the primary commercial species. Winter hibernation is a critical phase for productivity; however, outdoor survival rates remain a major challenge in farms located in colder regions. This two-year study aimed to adapt indoor hibernation—a practice typically associated with (semi-)intensive snail farming—to the IOSF system as a strategy to mitigate the high mortality rates associated with the sole use of Lutrasil frost cloth (LFC) for overwintering protection. Semiempirical field experiments were conducted across three commercial farms, testing different hibernation scenarios. Results demonstrated that micro shelters significantly reduced the labor time for snail collection compared to hand-picking. Post-hibernation weight loss varied among farms, with significantly higher losses observed in poorly insulated hibernation spaces, although post-purging values remained relatively uniform. The vast majority of snails survived indoor hibernation, yet inadequate thermal insulation yielded significantly higher mortalities despite comparable hibernation durations. Most deaths were attributed to environmental factors rather than predation. The present findings offer practical guidance for snail breeders in regions with colder winters, supporting the integration of indoor hibernation as a viable alternative in IOSF system farms.

(1) Background: Hibernation in Lutrasil-covered enclosures led to elevated mortality rates for Cornu aspersum on Romanian farms. This two-year study evaluated the feasibility of adapting indoor hibernation technology to the Italian outdoor snail farming (IOSF) system as a solution for overwintering mature C. aspersum snails. (2) Methods: Body weight, survival rates, and mortality factors during key hibernation phases (purging and overwintering) were monitored in three commercial snail farms using different hibernation scenarios. Labor efficiency was evaluated, comparing the use of micro shelters vs. hand-picking for snail collection. We analyzed post-purging/post-hibernation weight loss and mortality in hibernation spaces with and without proper thermal insulation. Mortality causes were also investigated. (3) Results: Using micro shelters significantly reduced labor time for snail collection. Weight loss during purging, but not during overwintering, were similar between groups. Post-hibernation survival ranged from 69% to 79% for comparable hibernation durations. Significantly lower survival was associated with significantly higher weight loss and using hibernation spaces with minimal thermal insulation. Predators exerted a very limited effect on post-hibernation survival, with most death appearing to be related to environmental causes. (4) Integrating indoor hibernation into the IOSF system is a promising strategy for the successful rearing of C. aspersum in colder climates.