中文摘要：

2013年10月—2014年3月,采用焦点动物法观察了小Tachybaptus ruficollis和凤头Podiceps cristatus的越冬潜水行为。小的平均潜水持续时间和暂停持续时间分别为（13.84 s±5.66 s）（n=1593）和（12.24 s±9.71 s）（n=1504）,凤头为（21.72 s±9.65 s）（n=793）和（17.88 s±11.68 s）（n=728）,均在越冬不同时期和昼间不同时段有所差异。小（1.13）和凤头（1.21）的潜水效率均较低,小的潜水效率更为稳定。2个物种中,仅小的暂停持续时间与前一次和后一次的潜水有极显著相关性。2种在潜水持续时间长及潜水效率高的时段均相似,但也产生了＂错峰＂等分化现象。本文还验证了潜水持续时间随体型增大而增长,温度下降会导致潜水效率下降等规律。

英文摘要：

From October 2013 to March 2014, the diving behaviors of little grebe Tachybaptus ruficollis and great crested grebe Podiceps cristatus were studied by focal-animal sampling method. The mean diving duration of P. cristatus （21.72 s ±9.65 s） （n =793） was longer than T. ruficollis （13.84 s±5.66 s） （n =1593）, so as the mean time at surface （17.88 s ± 11.68 s） （n =728） and （ 12.24 s ±9.71 s） （n = 1504）, respectively. Diving efficiency of T. ruficollis （1.13） was slightly lower than that of P. cristatus （1.21）, but more stable during the wintering period. For the two grebes, only surface duration of T. ruficollis was positively related to both duration of the preceding and the following diving. High values of diving duration and dive efficiency of the two grebes occurred in similar time but with different peak times. We also found that the diving dura-tion increased with the body size and the low temperature could cause a decline in diving efficiency.