Cold-season challenges: Behavioral adaptations of invasive <i>Procambarus clarkii</i> to rapid water level decline and shelter availability

To examine the effects of seasonal temperature variations on the burrowing behavior of Procambarus clarkii during the coldest months (November and January), studies were conducted under simulated hydrological and shelter conditions − rapid water level reduction (RWLR) and constant water level (CWL), with or without artificial shelters (S or /NS). P. clarkii behavior was monitored with high-definition infrared cameras. The behavioral distribution of P. clarkii varied by treatment. RWLR-NS treatment exhibited higher burrowing activity in November (20.94%) than in January (13.59%), while the total burrow count remained constant ( n = 5). RWLR-S treatment showed lower activity (November: 3.90%, January: 5.24%), with burrow counts of 4 and 3. Burrowing activity in CWL-S was negligible, with rates of 0.11% in November and 0.15% in January, corresponding to a single burrow observed in January. In CWL-NS, no burrowing was detected in November, while a slight increase to 0.35% and one burrow was recorded in January. Despite seasonal cooling, temperature exhibited no significant effect on burrowing, highlighting the species' ability to sustain essential survival behaviors ( e.g. , burrow maintenance) even under winter water level reduction. These findings highlight the remarkable adaptability of P. clarkii , allowing it to persist in fluctuating hydrological conditions despite seasonal temperature variations.