Cognitive flexibility, the ability to modify one’s decision rules to adapt to a new situation, has been extensively studied in many species. In fish, though, data on cognitive flexibility are scarce, especially in the wild. We studied a lekking species of cichlid fish in Lake Tanganyika, Aulonocranus dewindti. Males create sand bowers as spawning sites and maintain them by removing any objects falling into it. In the first part of our experiment, we investigated the existence of spontaneous decision rules for the maintenance of the bowers. We showed that if a snail shell and a stone are placed in their bower, fish prefer to remove the shell first. In the second phase of our experiment, we took advantage of this spontaneous decision rule to investigate whether this rule was flexible. We tested five individuals in a choice against preference task, in which the fish had to modify their preference rule and remove the stone first to be allowed to then remove the shell and have a clean bower. While there was no overall trend towards flexibility in this task, there was variation at an individual level. Some individuals increased their preference for removing the shell first, deciding quickly and with little exploration of the objects. Others were more successful at choosing against preference and showed behaviours suggesting self-regulatory inhibition abilities. Bower-building cichlids could therefore be a promising model to study cognitive flexibility, and other aspects of animal cognition in the wild.

认知灵活性，即修改决策规则以适应新情况的能力，已在许多物种中得到广泛研究。然而，对于鱼类来说，关于认知灵活性的数据很少，尤其是在野外。我们研究了坦噶尼喀湖中的一种慈鲷鱼，Aulonocranus dewindti。雄性会建造沙亭作为产卵地，并通过清除落入其中的任何物体来维护它们。在实验的第一部分，我们研究了维护凉亭的自发决策规则的存在。我们发现，如果将蜗牛壳和一块石头放在它们的凉亭里，鱼更喜欢先去除蜗牛壳。在我们实验的第二阶段，我们利用这个自发决策规则来研究这个规则是否灵活。我们在一项针对偏好的选择任务中测试了五个个体，其中鱼必须修改它们的偏好规则并首先移除石头，然后才能移除外壳并拥有一个干净的凉亭。虽然这项任务没有总体上趋于灵活性的趋势，但个体层面上存在差异。有些人更倾向于首先去除外壳，他们很快就做出了决定，而且很少对物体进行探索。其他人则更成功地做出反对偏好的选择，并表现出表明自我调节抑制能力的行为。因此，凉亭丽鱼科鱼可能是研究认知灵活性和野生动物认知其他方面的有前途的模型。