Interdaily water temperature variations were studied at a known spawning site of European grayling (Thymallus thymallus) in the Große Mühl River, Austria. Spawning activity was visually observed from a bridge where spawners were counted and their activity/behaviour documented twice a day. The spawning of grayling was documented for a temperature range of 7.8–11.5°C. Analysis of the collected data showed that spawning activity increases significantly when water temperatures rise during a day. In addition, the results showed a significant response in the relative water temperature increase, which was +3.5°C on average; however, the absolute temperature between periods of non-activity and spawning activity exhibited no significant differences.

中文翻译：

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由日间水温变化驱动的欧洲鳟鱼 (Thymallus thymallus) 的产卵活动：案例研究 Gr. 米尔河/奥地利

在奥地利 Große Mühl 河的一个已知的欧洲鳟鱼 ( Thymallus thymallus )产卵地点研究了日间水温变化。从桥上目视观察产卵活动，在那里对产卵者进行计数并每天记录两次它们的活动/行为。在 7.8-11.5°C 的温度范围内记录了鲑鱼的产卵。对收集到的数据的分析表明，当一天中水温升高时，产卵活动会显着增加。此外，结果显示相对水温升高有显着响应，平均为+3.5°C；然而，非活动期和产卵活动期之间的绝对温度没有显着差异。