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San Diego is known for its sun-filled weather and beautiful beaches. Anyone who visits or resides in this gorgeous city knows that it’s the perfect spot for whale and dolphin watching. Enjoy the best sightseeing on San Diego Bay with a professionally narrated tour of San Diego’s whale-watching hot spots. Join City Cruises San Diego on a Whale & Dolphin Watching Adventure as you search for Gray Whales, Blue Whales, Minke Whales, Fin Whales, dolphins, sea lions, marine birds, and much more. Get up close views of the bay’s wildlife as well as iconic landmarks from a new perspective. Onboard staff will provide live narration and details about the aquatic life and landmarks as you pass by for a memorable experience.
A great way to time your whale-watching adventure is to check out our Whale-Watching Naturalist Notes which include sightings and reports of whales, dolphins, and other birds and sea life. This blog-style report provides valuable insights that help future guests plan and enhance their experience. It can identify the best time for spottings, update on weather conditions, highlight active whale and dolphin species, and educate guests about local sea life.
瞭解聖地牙哥鯨魚
描述: 灰鯨的平均大小約為 11 至 15 米(36-50 英尺)長,重達 45,000 公斤(49.6 噸)。像其他鬚鯨一樣,雌性比雄性長得大。從上面看,灰鯨的身體兩端逐漸變細,呈深色石板色,可能看起來是斑駁的灰色。一般來說,老年鯨魚身上會出現如此多的藤壺和白色疤痕,以至於原始的石板顏色幾乎被掩蓋了。須板長不到 0.5 米(20 英寸),淡黃色至白色,有黃白色剛毛。口腔兩側通常有130到180個須板。喉嚨下側有兩到七個淺凹槽。灰鯨沒有背鰭,但有一個背駝峰,然後是背部後部的 8 到 14 個指關節(小凸起)。深缺口吸蟲寬約 3.7 米(10-12 英尺)。獨特的的心形打擊達到約3公尺(10英尺)的高度。
範圍:
灰鯨目前的活動範圍僅限於北太平洋東部。北太平洋西部也存在少於 100 頭灰鯨的種群,儘管其中一些鯨魚在北太平洋東部也被發現。歷史文獻和骨骼遺骸還表明,灰鯨以前生活在北大西洋,儘管它們在18世紀在大西洋被獵殺至滅絕。最近,在 2010 年和 2013 年,在大西洋發現了兩頭獨立的灰鯨;可能在那些年裡穿越一條新通航的西北航道。
遷移:
Gray whales spend the summer months in the Bering and Chukchi Seas and then leave for the breeding/calving lagoons along western Baja California, Mexico. They follow the longest migration route of any mammal on Earth, sometimes traveling nearly 16,000 to 22,530 km (10,000-14,000 miles) round trip. The southern migration begins in late September or early October. By December of most years, the first individuals pass along the California coast, with peak numbers passing by in early January. After their stay in the lagoons of Baja California, the whales begin their northward journey, starting in February and usually ending in late March. When migrating, gray whales generally stay within coastal waters. During the winter migration, they stay within 10 km (6 miles) of the shore. Mothers traveling north with their calves tend to travel even closer to the shore.
行為:
When traveling, a gray whale generally blows 3 to 5 times in 15 to 30-second intervals. Gray whales often raise their flukes out of the water before diving. Typical dives last 3 to 5 minutes, although a gray whale can stay submerged up to 15 minutes. During migration, gray whales swim at a 3 to 6 miles per hour (4.8–9.6 km/hr) speed. They are seen traveling by themselves, in pairs, or in small, loosely-organized groups. Gray whales are commonly seen breaching (launching out of the water and landing on their side with a splash), spy-hopping (peaking their head above the water for a look around) and lob-tailing/ tail slapping (slapping their flukes on the water with a loud splash).
繁殖:
灰鯨在八九歲時達到性成熟。交配主要局限於下加利福尼亞州西海岸的馬格達萊納灣、聖伊格納西奧瀉湖和斯卡蒙瀉湖,儘管它也經常發生在遷徙路線的南部。雌性在妊娠 12-13 個月後,兩年只生一次小牛。大多數灰鯨在下加利福尼亞州的瀉湖中分娩,儘管有些灰鯨在沿著南加州海岸向南旅行時分娩。像其他鯨類動物一樣,幼崽出生在水下,能夠立即游泳。犢牛至少在六個月的時間里依賴濃牛奶的飲食。它們在七到八個月時斷奶,儘管年輕的鯨魚可能會與母親一起多呆一年。
節食:
灰鯨是鬚鯨。灰鯨的上顎垂下沒有牙齒,而是 260 到 360 塊須(由角蛋白製成,與指甲和頭髮相同的材料)。灰鯨的大部分食物都是在北極的夏季獲得的。一小群灰鯨仍然在更遠的南方,以北加利福尼亞到阿拉斯加科迪亞克島的海岸為食。灰鯨的食物主要包括底棲兩棲動物(類蝦類甲殼類動物)和其他甲殼類動物,如成群的鳩鳥和中上層紅蟹,以及管蟲、蟹幼蟲和餌魚。為了覓食,灰鯨通常會側身打滾,吸一口含有大量獵物的泥土,然後通過鯨鬚將水和泥土排出。當它們在南方的繁殖地時,鯨魚大多會跑得很快,儘管眾所周知,它們會沿途吃零食。
捕食者:逆戟鯨(虎鯨)和人類。
保護狀況:19世紀的記錄顯示,在向南遷徙期間,每天有多達1000頭灰鯨經過聖地牙哥。在西海岸捕鯨者不受控制的捕獵之後,灰鯨幾乎瀕臨滅絕——事實上,它曾一度被認為已經滅絕。從1970年開始,該物種在東太平洋得到全面保護,其捕鯨前的種群規模在18,000至30,000之間取得了顯著的恢復。由於恢復,北太平洋東部灰鯨於1994年6月從瀕危物種名單中刪除。北太平洋西部的種群仍被列為「瀕危」。。
雖然東太平洋灰鯨目前沒有瀕臨滅絕或受到威脅,但它們偶爾會被活躍的和丟失或遺棄的漁具纏住。為了説明灰鯨和其他海洋動物,霍恩布洛爾游輪公司從可持續漁業中採購,用於其公共和私人餐飲遊輪,包括蒙特利灣水族館海鮮觀察計劃中標記為 「最佳選擇」的海鮮。您可以在家中、餐廳或度假時選擇使用可持續方法捕獲的海鮮來提供説明。
城市游輪邀請您進行一生的冒險
這些教育資訊是提供給城市游輪公司,供我們在 鯨魚和海豚觀賞冒險 中的客人與位於聖地牙哥巴爾博亞公園的聖地牙哥自然歷史博物館合作提供的。 (www.sdnhm.org)
原始發佈日期: June 16, 2019