Thursday, November 1, 2012

Humbling

  

The lingering spout of a Humpback Whale (Megaptera novaeanglieae) at Cordell Bank on 26 October 2012.  [A Black-footed Albatross is heading left above the horizon.]

We saw a few humpbacks and several Blue Whales offshore, and a couple of Gray Whales very close to Bodega Head.

Humpback Whale spouts have a bushy shape and reach ~2.5-3 meters high (8-10 feet).  Humpbacks may blow 4-8 times at 15-90 second intervals before a deeper dive.  Dives may last 3-15 minutes, or up to 40 minutes.
 
Humpbacks often appear black.   One individual revealed its arching back and knobby dorsal fin (next photo).  


I'm often asked how to tell Humpback Whales and Gray Whales apart.  To my eye, the spouts are fairly similar.  Gray Whale spouts are also bushy and reach up to 3-4 meters high (10-13 feet).  They average 3-6 blows at 15-30 second intervals before deeper dives, and their dives may last 3-10 minutes or up to 25 minutes. 

To compare, here are two pictures the first is a pair of Humpback Whale spouts from 26 October and the second is a Gray Whale spout seen from Bodega Head on 5 September.

If you see a spout like this, keep watching for the color of the back,  whether there is a dorsal fin, and if the flukes are lifted above the water.

- Humpbacks appear black, while Grays appear gray

- Humpbacks have dorsal fins, while Grays lack them

- Both species may lift their flukes about the surface when taking deeper dives, but Humpbacks lift them more frequently than Grays 

- Humpback flukes are broader, with pointed tips and a serrated edge, while Gray Whale flukes are more compact and rounded with a convex edge

- Gray Whales are often seen very close to shore, while Humpbacks are more common offshore


No matter what species you see or where you see them, it's always humbling to be in the presence of whales.


P.S.  The facts about spouts and dives came from one of my favorite field guides: Whales, Dolphins, and Other Marine Mammals of the World by Hadoram Shirihai and Brett Jarrett (2006).

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