加州Santa Monica海湾鳍足类的生态学(英文)

Pinniped ecology in Santa Monica Bay, California

研究了加州Santa Monica海湾鳍足类的生态学。从1997-2007年乘船调查了277次,发现海狮(Zalophus californianus)是最常见的动物(89 %,见到的次数为1393次) ,其次是港海豹(Phoca vitulina richardsi, 8 %,n=131)和北象海豹(Mirounga angustirostris, 1 %,n=15)。在29 %的遇见次数(观察到瓶海豚205次)中,发现海狮(偶尔也发现港海豹)与瓶鼻海豚集群(Tursiops truncatus) ;短喙真海豚(Delphinus delphis)与长喙真海豚(D·capensis)在53 %的遇见次数(遇见真海豚次数n=155)中,发现短喙真海豚(Delphinus delphis)与长喙真海豚(D·capensis)集群;一般在沿岸水域(离岸边距离<500 m)见到海狮和港海豹,但在整个海湾也能见到,表现出这两个物种对海底峡谷的偏爱。北象海豹仅见于近海,主要在海底峡谷附近。经常看到海狮、港海豹和北象海豹游动(50 %,n=728)、进行热调节(14 %,n=205)、以及取食(3·2 %,n=47) ,但几乎见不到有社会性活动(0·21 %,n=3)

We investigated pinniped ecology at sea in Santa Monica Bay, California. Animals were studied during 277 boat-based surveys conducted in 1997 - 2007 documenting that California sea lion Zalophus californianus was the most observed species （89 % , n sightings = 1393）, followed by harbor seal （Phoca vitulina richardsi; 8 % , n sightings = 131 ）, and northern elephant seal （Mirounga angustirostris; 1% , n sightings = 15）. Sea lions, and occasionally harbor seals, were found in aggregations with bottlenose dolphins Tursiops truncatus in 29% of the sightings （n bottlenose dolphin sightings = 205）, sbort-boaked common dolphins Delphinus delphis and long-beaked common dolphins D. capensis in 53% of the sightings （n common dolphins = 155）. Sea lions and harbor seals were regularly observed in coastal waters （ 〈 500 m from shore） but also in the entire bay, with both species showing a preference for submarine canyons. Northern elephant seals were only seen in offshore waters and mostly in proximity of the canyons. The three species were frequently observed traveling （50% , n = 728）, thermoregulating （14% , n = 205）, and feeding （3.2%, n = 47） but rarely socializing （0.21%, n = 3）. This is the first long-term study on at-sea distribution, occurrence, frequency and behavior of pinnipeds in Santa Monica Bay