Cecilia Hélène, Arnoux Sandie, Picault Sébastien, Dicko Ahmadou, Seck Momar Talla, Sall Baba, Bassène Mireille, Vreysen Marc, Pagabeleguem Soumaïla, Bancé Augustin, Bouyer Jérémy, Ezanno Pauline
INRAE, Oniris, BIOEPAR, 44300 Nantes, France.
Cirad, INRAE, ASTRE, University of Montpellier, Montpellier, France.
Proc Biol Sci. 2021 Feb 10;288(1944):20202810. doi: 10.1098/rspb.2020.2810. Epub 2021 Feb 3.
Spatio-temporally heterogeneous environments may lead to unexpected population dynamics. Knowledge is needed on local properties favouring population resilience at large scale. For pathogen vectors, such as tsetse flies transmitting human and animal African trypanosomosis, this is crucial to target management strategies. We developed a mechanistic spatio-temporal model of the age-structured population dynamics of tsetse flies, parametrized with field and laboratory data. It accounts for density- and temperature-dependence. The studied environment is heterogeneous, fragmented and dispersal is suitability-driven. We confirmed that temperature and adult mortality have a strong impact on tsetse populations. When homogeneously increasing adult mortality, control was less effective and induced faster population recovery in the coldest and temperature-stable locations, creating refuges. To optimally select locations to control, we assessed the potential impact of treating them and their contribution to the whole population. This heterogeneous control induced a similar population decrease, with more dispersed individuals. Control efficacy was no longer related to temperature. Dispersal was responsible for refuges at the interface between controlled and uncontrolled zones, where resurgence after control was very high. The early identification of refuges, which could jeopardize control efforts, is crucial. We recommend baseline data collection to characterize the ecosystem before implementing any measures.
时空异质的环境可能导致意想不到的种群动态。我们需要了解有利于大规模种群恢复力的局部特性。对于病原体媒介，如传播人类和动物非洲锥虫病的采采蝇，这对于制定目标管理策略至关重要。我们利用实地和实验室数据建立了一个采采蝇年龄结构种群动态的时空机制模型。该模型考虑了密度和温度依赖性。所研究的环境是异质的、破碎的，且扩散受适宜性驱动。我们证实温度和成虫死亡率对采采蝇种群有强烈影响。当均匀增加成虫死亡率时，在最冷和温度稳定的地点，控制效果较差且诱导种群更快恢复，从而形成了避难所。为了优化选择控制地点，我们评估了处理这些地点的潜在影响及其对整个种群控制的贡献。这种异质控制导致种群数量类似地减少，但个体分布更分散。控制效果不再与温度相关。扩散导致在控制区和未控制区之间的界面形成避难所，在这些地方控制后种群复苏非常高。尽早识别可能危及控制努力的避难所至关重要。我们建议在实施任何措施之前收集基线数据以表征生态系统。
