Roe Deer and Plant Phenology Nexus – Match or Mismatch?

Plasticity and factors driving parturition dates of ungulates is a topic that has been addressed in many studies. These factors potentially give us clues about a possible trophic mismatch between the timing of seasonal events and resources due to an earlier onset of phenological spring introduced by climate change. Particularly, roe deer (Capreolus capreolus L.), the most widespread and abundant ungulate in Central Europe, has been a species of great concern. As an income breeder, it must finance the energy-demanding end of gestation and lactation by currently available resources in spring. Yet, roe deer is the only artiodactyl species known to undergo embryonic diapause, a temporal suspension of embryonic development, for four to five months after mating in summer. Hence, it could potentially adjust the end of embryonic diapause to shifting environmental conditions to match the parturition of their offspring with the advancing greening in spring. Potentially resulting shifts in parturition timing in May and June are also of great interest to farmers as parturition and rearing of fawns coincide with annual spring mowing. Due to the fawns’ hiding strategy to protect themselves from natural predators, they often fall victim to approaching mowing machinery. Although farmers are legally obliged (in Germany) and are already untiringly searching meadows before mowing, not all fields can be searched simultaneously when mowing is constrained to short time windows due to periods of favourable weather for hay and silage production. Therefore, knowledge about the much-debated plasticity to environmental conditions in roe deer may provide helpful information for preventing accidental mowing death of fawns in spring by anticipating when most of the young and immobile fawns are forecasted to be present in the meadows and allocating targeted measures.