Grey seals have become an important part of the ecosystem in the southern North Sea over the last 50 years. However, little is known about their spatial utilization of the German North Sea, especially in relation to the dispersal and behaviour of grey seal pups after weaning. We investigated these little-known aspects by recording the movements of 11 grey seal pups born at the largest German colony for 1–9 months after leaving the colony between 2015 and 2017. The individuals moved widely throughout the southern North Sea, including some individuals that moved far along the Danish coast or to Dutch and UK waters. A point process modelling approach revealed that pups increased their distance to Helgoland during the first 70 d at sea. The frequency of inferred foraging behaviour increased until week 7 and decreased afterwards, whereas fast travelling behaviour increased throughout the whole study period. These findings reflect the transition from naive to more experienced pups, with gradual increases in foraging effort, range and efficiency to account for their increasing energy demands for survival and growth. This study provides the first characterization of the dispersal, behaviour, and spatial utilization of recently weaned grey seal pups in the southern North Sea, which profoundly extents our knowledge of an increasingly important top predator in that area.

中文翻译：

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最近断奶的灰海豹幼崽在北海南部的广泛分布

在过去的50年中，灰海豹已成为北海南部生态系统的重要组成部分。但是，对于它们在德国北海的空间利用知之甚少，尤其是在断奶后灰海豹幼崽的扩散和行为方面。我们记录了2015年至2017年离开德国殖民地1到9个月后出生在德国最大殖民地的11只灰海豹幼崽的运动，从而调查了这些鲜为人知的方面。这些个体在北海南部的广泛移动，包括一些沿丹麦海岸或荷兰和英国海域走得很远。点过程建模方法显示，幼仔在海上的前70天增加了它们与Helgoland的距离。推断的觅食行为的频率增加到第7周，此后减少，而在整个研究期间，快速旅行行为有所增加。这些发现反映了从幼稚到经验丰富的幼犬的转变，随着觅食努力，范围和效率的逐步提高，可以解释它们对生存和生长的不断增长的能量需求。这项研究提供了北海南部最近断奶的灰海豹幼崽的扩散，行为和空间利用的第一个特征，这深刻地扩展了我们对该地区日益重要的顶级捕食者的了解。