Niemi Marja, Nykänen Milaja, Biard Vincent, Kunnasranta Mervi
Department of Environmental and Biological Sciences University of Eastern Finland Joensuu Finland.
Natural Resources Institute Finland Joensuu Finland.
Ecol Evol. 2023 Jul 3;13(7):e10264. doi: 10.1002/ece3.10264. eCollection 2023 Jul.
Seasonal changes in diel haul-out patterns of the lacustrine Saimaa ringed seal () were studied using a combination of satellite telemetry and camera traps during 2007-2015. We found the haul-out activity patterns to vary seasonally. Our results show that during the ice-covered winter period before the seals start their annual molt, the peak in haul-out generally occurs at midnight. Similarly, during the postmolt season of summer and autumn when the lake is free of ice, the haul-out is concentrated in the early hours of the morning. In contrast, over the spring molting period, Saimaa ringed seals tend to haul out around the clock. The spring molt is also the only period when a slight difference in haul-out behavior between the sexes is observed, with females having a haul-out peak at nighttime while the males have a less visible diel pattern. According to our results, the diel haul-out patterns of Saimaa ringed seals are similar to the ones of marine ringed seals. Gathering information on haul-out activity is important in order to safeguard the natural patterns of Saimaa ringed seals in areas that are prone to disturbance from human activities.
2007年至2015年期间，利用卫星遥测和相机陷阱相结合的方法，对湖泊型塞马环斑海豹（）的昼夜上岸模式的季节性变化进行了研究。我们发现上岸活动模式随季节变化。我们的研究结果表明，在海豹开始年度换毛之前的冰封冬季，上岸高峰通常出现在午夜。同样，在夏季和秋季的换毛后季节，当湖面无冰时，上岸集中在凌晨时分。相比之下，在春季换毛期，塞马环斑海豹倾向于全天上岸。春季换毛也是唯一观察到两性上岸行为略有差异的时期，雌性在夜间有上岸高峰，而雄性的昼夜模式不太明显。根据我们的研究结果，塞马环斑海豹的昼夜上岸模式与海洋环斑海豹的相似。收集上岸活动信息对于保护塞马环斑海豹在容易受到人类活动干扰地区的自然模式非常重要。
