First Choice Holidays will capitalise on travellers' growing adventurousness by buying Quark Expeditions - the only firm to offer polar ice-breaker trips. A trading update yesterday said First Choice sales for the coming summer season were little changed in its mainstream division, but were up 24% in its specialist unit. Increased air passenger duty and fuel costs and investment in two more long-haul planes would result in lower margins for the 2006/07 winter season. First Choice, seeking a merger with TUI's tourism division, said it continued to see good acquisition opportunities.