WHALE OF A SHOW : BLUES, HUMPBACKS ARE STARS.

Byline: Bryan Winchell Special to the Daily News

While Baja-bound and Alaska-returning gray whales are the darlings of Southern California waters in winter and early spring, late spring and summer belong to the lesser-known humpback and blue whales, especially in the Santa Barbara Channel.

``Those are the two big stars of the summer season,'' said Alisa Schulman-Janiger, whale census director with the Los Angeles Chapter of the American Cetacean Society. ``We've had as many as 50 blues and 50 humpbacks in a single day. This has been going on fairly regularly for a few years now.''

The ``humpies'' and blues feed north of the Channel Islands, particularly from Santa Cruz to San Miguel islands. Humpbacks already have been sighted this season, news that came as a surprise to Schulman-Janiger because of their early arrival.

On a recent channel trip to catch the last, straggling gray whales, sightseers on a charter boat based here watched with fascination for more than an hour as two playful humpbacks frolicked about. An ACS whale census taker spotted a humpback off Point Vicente, on the Palos Verdes Peninsula, less than three weeks ago.

The whales are relatively new inhabitants of Southern California - showing up in great numbers only this decade, particularly in 1992 - and their numbers now represent a significant portion of the world's population. In fact, the chances of seeing a blue in the Santa Barbara Channel are better than anywhere else in the world, experts note. Of the 10,000 whales worldwide, 2,000 travel the coast of California and Mexico, and some 400 have inhabited the channel during the summer.

As for humpbacks, 700 of the world's 10,000 to 20,000 are found off the California, Oregon and Washington coasts, with up to 250 summertime residents in the channel.

Marine researchers point to an explosion in the concentration of krill - a small shrimplike creature whales feed on - in the channel as the best explanation for the sightings.

John Calambokidis, a humpback specialist with Olympia, Wash.-based Cascadia Research, said the currents along the California coast bring nutrient-rich waters to the surface, which is ideal for krill and small fish populations to flourish.

Because the currents are ever-changing, he explained, hot spots for blue and humpback whales move with the food. The Santa Barbara Channel has been scorching for the past five years.

``It's a krill machine,'' Fred Benko, captain of the Condor charter boat out of Santa Barbara, said of the 3- to 5-mile area off the northern faces of Santa Rosa and San Miguel islands.

Though the blues, which can measure to 100 feet, primarily stay in this area, the humpbacks are known to stretch farther east, off the shores of Santa Cruz and Anacapa islands, Schulman-Janiger said.

Another possible explanation for the increased sightings is that the worldwide population of the two species has increased slightly since hunting the mammals was restricted globally in the 1960s.

Whatever the reason, researchers and tourists from around the world flock to the region to get a glimpse of these behemoths.

Benko, who enjoys a summertime patronage of about 10,000 whale-watchers, said viewers are fortunate.

``In the history of the world, there are very few people who have had a chance to see blue whales in their natural habitat,'' Benko said.

It's quite a scene when they do.

``You hear people hooping and hollering; they get real excited when they see these big animals,'' Benko said.

The differences between the cetaceans are primarily size and movement.

The blue, which can travel up to 30 miles per hour, is the largest animal ever to inhabit the planet. ``It looks like an island going by,'' Schulman-Janiger said.

Blues are blue-gray in color, have a tall, straight spout of up to 30 feet, a small, curved dorsal fin located near the back of the body and usually travel in pairs.

Humpbacks are more acrobatic, sometimes thrusting all the way out of the water, a maneuver known as breaching. They measure 40 to 50 feet, are black on the dorsal side, travel in groups of up to five and usually lift their flukes upward, showing a black-and-white patterned underside that is distinctive to each animal.

Though the blues and humpbacks are the main attraction, 17 to 20 other whale species travel the channel, most notably minke, fin and killer whales, or orcas. In addition, sea lions and seals dot the islands and numerous types of dolphins play in the channel, sometimes with the whales.

If going, Schulman-Janiger recommends bringing binoculars, a camera, plenty of film, seasick medication, layers of clothing and a lot of patience. But there's a pretty good chance of witnessing the great cetaceans.

``We see humpbacks almost every day and blues a couple of times a week,'' Benko said. ``They come here to feed, so they stay several weeks. I'm convinced they recognize the boat, because when we move into the area and shut off the engine they come over to see us.''

CAPTION(S):

3 Photos

Photo: (1-2-3--color) A humpback whale showing its fluke s, above, passes in review while a breaching humpback is on the left and a group of common dolphins are on the right. Late spring and summer are when humpback and blue whales can be seen in profusion north of the Channel Islands, particularly from Santa Cruz to San Miguel islands.

(1,3) Alisa Schulman-Janiger / Special to the Daily News

(2) Hugh Ryono / Special to the Daily News