Data - Leech removal is not the primary driver of basking behavior in a freshwater turtle

Leaving the water to bask (usually in the sun) is a common behavior for many freshwater turtles, with some species also engaging in “nocturnal basking.” Ectoparasite removal is an obvious hypothesis to explain nocturnal basking and has also been proposed as a key driver of diurnal basking. However, the efficacy of basking, day or night, to remove leeches has not been experimentally tested. Therefore, we examined the number of leeches that were removed from Krefft’s river turtles (Emydura macquarii krefftii) after experimentally making turtles bask at a range of times of day, durations, and temperatures. Turtles had high initial leech loads, with a mean of 32.1 leeches per turtle. Diurnal basking under a heat lamp for 3 h at ~28°C significantly reduced numbers of leeches relative to controls. In diurnal trials, 90.9% of turtles lost leeches (mean loss of 7.1 leeches per turtle), whereas basking for 30 mins under the same conditions was not effective (no turtles lost leeches, and all turt...对于多数淡水龟而言，离水晒背（通常为日光浴）是常见行为，部分物种还会进行"夜间晒背"。去除体外寄生虫是解释夜间晒背行为的直观假说，同时也被视为驱动日间晒背的核心因素之一。然而，无论是日间还是夜间晒背，其去除水蛭的效果均未经过实验验证。为此，我们通过实验设置不同时段、时长与温度条件，让克雷夫特河龟（Krefft’s river turtle，Emydura macquarii krefftii）进行晒背，随后统计其体表脱落的水蛭数量。受试龟初始水蛭负载量较高，平均每只个体携带32.1只水蛭。与对照组相比，在约28℃的加热灯下进行3小时日间晒背，可显著减少龟体表的水蛭数量：在该日间晒背实验中，90.9%的受试龟出现水蛭脱落，平均每只龟脱落7.1只水蛭；而在相同条件下仅晒背30分钟则未产生效果（无龟出现水蛭脱落，且所有受试...