ML Macadamia Orchards LP swung to a loss in the fourth quarter from a profit in the same period a year earlier mainly because of higher production costs and interest expenses, the company reported today.

The Hilo-based macadamia grower lost $1 million during the October-through-December period, compared with a profit of $96,000 in the fourth quarter of 2009.

Macadamia nut sales rose to $7 million in the fourth quarter from $5.4 million a year earlier. However, the cost to produce the nuts rose to $7.3 million from $4.9 million a year earlier. For all of 2010 nut sales were virtually unchanged from 2009 at $12.2 million pounds.

The fourth quarter capped a year in which a drought in the Kau region caused macadamia nut yields there to fall by 4 million pounds, or 31 percent. That was partially offset by higher hields in the Keeau region, additional production from newly acquired orchards and a slightly higher average nut price, the company said. ML Macadamia lost $1.5 million in 2010 after recording a profit of $195,000 in 2009.