德国一家动物园表示，他们的六只雄性同性恋企鹅仍然不和从瑞典来的同类雌性交配。

这家动物园位于德国北部城市不来梅港，动物园主管海克·许克说，问题是雌性洪堡企鹅向来很害羞，不会主动接近雄性。

许克说："瑞典企鹅不会主动出击。"

去年，动物园为了让雄性交配，引进了雌性企鹅，以防止洪堡企鹅灭绝。

许克说，去年她对他们的做法很乐观，认为将会获得成功。因为动物园管理员有一次看到，一只雌性企鹅成功地"分开"了一对雄性企鹅。

这家动物园里有10只雄性企鹅，其中六只非常喜欢和同性呆在一起，成了三对同性恋伴侣。

"转变"企鹅的性倾向，让他们和异性交配的做法引发了同性恋权利组织的强烈反对。

这家动物园星期三在它的网站上发表声明，反驳同性恋组织近日对他们的批评。

声明中说："这些企鹅中哪怕能组成一对异性伴侣，顺利生下一个蛋，长成一只小企鹅，我们也会很高兴的。"

"但是，我们当然也同意两只同性企鹅在一起，我们不是强调要异性恋，我们去年就曾在这一问题上被谴责。"

Six gay penguins at a German zoo are still refusing to mate with females of the species flown in from Sweden in 2005, the zoo said.

The problem was that the female Humboldt penguins have proven too shy in their advances, the director of the zoo in the northern port city of Bremerhaven said.

"The Swedes will not make the first move," Heike Kueck said.

The females were flown in last year in a bid to bring the males to mate and help save the Humboldt species from extinction.

Kueck said last year she was optimistic the initiative would be successful because zoo keepers had noticed that at one point a female penguin had managed to cause a couple of males to "separate".

The zoo has 10 male penguins of which six have shown strong signs of preferring male company and formed couples among themselves.

The initiative to "turn" the penguins and make them mate had prompted a furious response from gay rights groups.

In a statement posted on its Internet website, the zoo on Wednesday sought to defend itself from fresh criticism.

"We will be delighted if the penguins form even one heterosexual couple and manage to produce first an egg, and then a little one," it said.

"But of course we accept the male couples that have formed and we are not trying to enforce heterosexuality, as we were accused of doing last year."