长哨 meaning in English

long whistle

Different whistles were compared to the dolphins behaviour and to the number of boats around them . it was determined that while socialising , dolphins are more talkative , that is , they whistled more often and the whistles were longer and more complicated
我们根据海豚的行为及围绕四周的船只数目去比较不同的哨叫声，发现中华白海豚在集体行动时更爱说话：意思是它们的哨叫频率更高时间更长哨叫模式亦更复杂！