Wildlife Research Unit (UIRCP), Universidad de Córdoba, Córdoba, Spain.
Biology and Ethology Unit, Universidad de Extremadura, Cáceres, Spain.
PLoS One. 2022 Dec 1;17(12):e0278367. doi: 10.1371/journal.pone.0278367. eCollection 2022.
Body condition for reproduction in capital breeders such as the red deer (Cervus elaphus) is mostly determined by their stored energy reserves. Thus, environmental conditions and resource availability may affect reproductive performance and breeding success. In warm Mediterranean regions, current climate change is driving to a hotter and drier scenario that is expected to affect the biology and dynamics of many populations. We examined the impact of these local climate variations on red deer body condition and the relationship with female reproductive phenology and breeding success. We used satellite information of landscape vegetation along with a 22-year data series of direct field behavioural observations during the rutting season in Doñana National Park (SW Spain). We analyzed faecal nitrogen content (FN) from faeces collected during the rut. We found that poor vegetation availability in drier years was related to worse body condition of deer (measured by FN) and a delay in the rutting season, which associated with lower reproductive rates (measured by the proportion of females with calves observed the next year). We also evidenced an interesting interaction between environmental conditions in consecutive years on the timing of breeding season, with timing of breeding being more delayed when previous year resource availability was high and many females bred, and the consecutive one was poor, so females hardly recovered condition and the rut occurred later. These findings highlight the carry-over effect of reproduction in capital breeders and the potential impact of climate-change conditions on red deer breeding.
繁殖期资本种畜（如马鹿）的身体状况主要由其储存的能量储备决定。因此，环境条件和资源可用性可能会影响繁殖性能和繁殖成功率。在地中海温暖地区，当前的气候变化正导致气候变得更加炎热和干燥，预计这将影响许多种群的生物学和动态。我们研究了这些局部气候变化对马鹿身体状况的影响，以及与雌性繁殖物候和繁殖成功率的关系。我们使用了多纳纳国家公园（西班牙西南部）在发情季节进行的 22 年直接野外行为观察数据系列以及景观植被的卫星信息。我们分析了发情期间从粪便中收集的粪便氮含量（FN）。我们发现，干旱年份植被的可利用性较差与鹿的身体状况较差（由 FN 测量）和发情季节的延迟有关，这与繁殖率较低（由第二年观察到的带小牛的雌性比例测量）有关。我们还证明了连续几年环境条件对繁殖季节时间的有趣相互作用，当前一年资源可用性高且有许多雌性繁殖时，繁殖时间会更延迟，而连续一年资源可用性较差，因此雌性几乎无法恢复身体状况，发情期会推迟。这些发现强调了资本种畜繁殖的延续效应，以及气候变化条件对马鹿繁殖的潜在影响。
