Migration statistics and animal biometrics for mule deer that migrated long-distances (2011–2020), Wyoming, USA

Billions of animals migrate to track seasonal pulses in resources. Optimally timing migration is a key strategy, yet the ability of animals to compensate for phenological mismatches en route is largely unknown. We studied a population of mule deer (Odocoileus hemionus) in Wyoming that lack reliable cues on their desert winter range, causing them to start migration 70 days ahead to 52 days behind the wave of spring green-up. By adjusting movement speed and stopover use, however, individual deer arrive at the summer range within an average 6-day window. Late migrants move 2.5 times faster and spend 72% less time on stopovers than early migrants, which allows them to catch the green wave. Ungulates, and potentially other migratory species, possess cognitive abilities to recognize where they are in space and time relative to key resources. Such behavioral capacity may allow migratory taxa to maintain foraging benefits amid rapidly changing phenology.

数十亿动物通过迁徙追踪资源的季节性脉动。精准把控迁徙时机是一项关键生存策略，然而动物在迁徙途中补偿物候失配的能力，目前仍未得到广泛探明。我们对怀俄明州的一处骡鹿（Odocoileus hemionus）种群展开了研究：该种群的沙漠越冬栖息地缺乏可靠的环境线索，导致其迁徙启动时间相较于春季返青浪潮，存在提前70天至滞后52天的差异。但通过调整行进速度与中途停歇行为，个体骡鹿最终抵达夏季栖息地的时间偏差仅为平均6天的窗口。与早出发的迁徙个体相比，晚出发的个体行进速度快2.5倍，中途停歇耗时减少72%，这使得它们能够追上春季返青的浪潮。有蹄类动物，乃至其他潜在的迁徙物种，具备认知能力，能够识别自身相对于关键资源的时空位置。这种行为能力或能让迁徙类群在快速变化的物候背景下，仍能维持觅食收益。