but when the conditions are right as now
但如果条件允许譬如现在

Question

for at this stage they're flightless.
在这一阶段它们还不能飞
They find new feeding grounds by following the smell of sprouting grass.
它们循着萌发的草香寻找新的用餐场所
Normally it takes four weeks for hoppers to become adults,
一般说来若虫需要经过4周才能变成成虫
but when the conditions are right as now
但如果条件允许譬如现在
their development switches to the fast track.
它们的生长过程就会切换到快车道
As the vegetation in one place begins to run out
当一个地方的植物即将吃光时
the winged adults release pheromones - scent messages,
长着翅膀的成虫便释放出信息素即一些气味信号

来自《行星地球第一季第五集 Planet Earth S01E05 沙漠》第 308 行

but when the conditions are right as now 但如果条件允许 譬如现在