Wildlife populations, especially in the tropics, have declined drastically in the past four decades and the trend was especially marked in low-income countries, according to a report released Wednesday by the World Wide Fund for Nature.

The WWF on Thursday cited its report to lobby the governments participating in the 10th Conference of the Parties to the Convention on Biological Diversity, or COP10, that starts next week in Nagoya to reach agreements promoting the preservation and fair use of biodiversity.

"COP10 is an important and critical meeting. We cannot afford Nagoya to be a failure," Gunter Mitlacher, one of the representatives of the international conservation group, said in Tokyo.