They actually rely on their daylight vision and cannot fly during the night with no moonlight.

实际上，它们依靠的是昼视觉，在没有月光的夜晚则无法飞行。

youdao

Owls often fly out at night. They can catch mice.

猫头鹰通常在晚上飞到外面觅食。它们会抓老鼠。

youdao

CH-47s pilots in Iraq were told to fly only at night.

在伊拉克的CH-47飞行员被告知只在夜间飞行。

youdao

The bats fly to nearby river valleys to feed on night-flying insects.

VOA: special.2011.04.11

With the help of Chiara Cirelli, who also works at the University of Wisconsin, Dr Tononi has created a mutant fruit fly that sleeps only two or three hours a night. (A normal fly sleeps between eight and 14 hours.) The mutation itself is in a gene for a nerve-cell protein of a type known as an ion channel.

ECONOMIST: Memory formation

Some fly by night piece of space junk that doesn't even have a name?

NPR: A Down-to-Earth View of the Planet Debate

The aircraft had the bat-wing insignia of her son's unit, the "Vampires" -- so-called because they usually fly at night.

CNN: Families of captured pilots wait, hope