Carnival Cruise Lines has reported net income of $41.6 million on revenues of $284.7 million for its second quarter, ending May 31, 1989, compared to $52 million on revenues of $158.7 million for the same quarter in 1988.

Net income for the six months ended May 31, 1989 was $87.9 million on revenues of $516.4 million compared to net income of $98 million on revenues of $311.6 million for the same period in 1988.

In a prepared statement, Carnival attributed the lower earnings in the second quarter to the seasonality of Holland America Line and its affiliated companies, which Carnival acquired in January of this year. According to Carnival, HAL's volume of business is greatest during the summer tourist season in Alaska and particularly in the third quarter.

Carnival reported that revenues increased in the latest three months by 79 percent and for the first half of its fiscal year by 66 percent, because of the additional capacity provided by the cruise ships of HAL and its affiliates; the opening of the first phase of Carnival's Crystal Palace Resort and Casino in Nassau; and the acquisition of the Cable Beach Hotel adjacent to the casino last December.

In its second quarter, Carnival achieved an average occupancy level of 106.8 percent, carrying 205,405 passengers. This is a 38 percent increase compared to the second quarter last year.

For the first six months, the company achieved a fleetwide occupancy level of 106.6 percent, carrying 382,236 passengers, up 33 percent from the same period last year. Though passenger counts were up dramatically, Carnival attributed the decline in overall occupancy levels to the lower occupancy levels traditionally achieved by HAL and Windstar vessels, which Carnival said is customary for companies operating in the premium segment of the market.

Based on numbers of passengers carried, Carnival claims to the largest cruise line in the world. The combined company fleets of Carnival, HAL and Windstar are comprised of 14 ships operating in Alaskan waters, the Caribbean, South Pacific and the Mediterranean. In addition, three 2,050 vessels are under construction for Carnival at Wartsila in Finland, scheduled for delivery in 1990, '91 and '92. There are also rampant rumors of negotiations that have Carnival placing a three-ship order for HAL with Fincantieri.