Conservation Biology Department, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico.
Marine Ecology Department, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico.
PLoS One. 2022 Jul 6;17(7):e0270129. doi: 10.1371/journal.pone.0270129. eCollection 2022.
Humans frequently interact with Pacific harbor seals (Phoca vitulina richardii) at Punta Banda Estuary, Baja California, Mexico, due to the high incidence of recreational activities people undertake there. The immediate effect of these interactions is that seals flush to the water, reducing their time on land and, probably, increasing their energy expenditure. On-land observations were used to study the impact of different sources of disturbance on seal behavior and evaluate their effect on the amount of time dedicated to nursing over three pupping seasons, (2015-2017), with 0.58-0.81 disturbance events/hour recorded over the entire sampling period. Terrestrial vehicles were the source with the highest disturbance rate (number of disturbance events/h), followed closely by pedestrians. However, the proportion of seals affected was highest when pedestrians were the disturbance source. Recovery events (seals hauling out after flushing) occurred after 34% of disturbance events, after less than half of which the same number of hauled-out seals as there were prior to the disturbance were observed. Recovery time varied among the years studied, of which 2017 saw the longest recovery time. In addition, pedestrians were the disturbance source with the longest recovery time. Given that resting on land is essential for pup survival, which depends on both the establishment of the mother-pup bond from birth and its maintenance throughout nursing, flushing behavior may have significant implications for the entire colony during the nursing season. We recorded a decrease in nursing duration, which did not return to the same level even after recovery and the resumption of nursing. Terrestrial vehicles were found to be the disturbance source that shortened nursing events most significantly.
人类经常在墨西哥下加利福尼亚州的班达角河口（Punta Banda Estuary）与太平洋港海豹（Phoca vitulina richardii）互动，因为人们在那里进行的娱乐活动很多。这些互动的直接影响是海豹被驱赶回水中，减少了它们在陆地上的时间，并且可能增加了它们的能量消耗。在陆地上的观察被用来研究不同干扰源对海豹行为的影响，并评估它们对三个繁殖季节（2015-2017 年）中哺乳时间的影响，整个采样期间每小时记录 0.58-0.81 个干扰事件。陆地车辆是干扰率最高（干扰事件数/小时）的干扰源，紧随其后的是行人。然而，当行人是干扰源时，受影响的海豹比例最高。在 34%的干扰事件后发生了恢复事件（海豹在驱赶后浮出水面），在不到一半的干扰事件后，观察到浮出水面的海豹数量与干扰前相同。恢复时间在研究的年份中有所不同，其中 2017 年的恢复时间最长。此外，行人是干扰源，恢复时间最长。由于在陆地上休息对幼崽的生存至关重要，而幼崽的生存取决于从出生时建立的母子关系及其在哺乳期间的维持，驱赶行为可能对整个繁殖季节的海豹群体产生重大影响。我们记录到哺乳时间的减少，即使在恢复和重新开始哺乳后，也没有恢复到相同的水平。陆地车辆被发现是缩短哺乳时间最显著的干扰源。
