SAMARKAND, Uzbekistan— Governments today adopted critical international trade protections for hornbills and songbirds, two groups of birds suffering steep declines due to rampant illegal and unsustainable trade.

The measures passed at the 20th Conference of the Parties to the Convention on International Trade in Endangered Species of Wild Fauna and Flora, or CITES.

“The governments at CITES deserve major credit for passing these proposals, which offer essential protections to African hornbill species and other birds that are truly on the brink,” said Chris R. Shepherd, a senior conservation advocate at the Center for Biological Diversity. “Without international regulations and controls, there are simply no mechanisms to confront the organized criminal networks driving this crisis.”

Eight African nations successfully proposed listing seven African hornbill species in the genera Bycanistes and Ceratogymna. Sporting large upper beaks, or mandibles, these iconic birds are increasingly targeted for their heads, sold internationally as curios, and to a lesser extent, for traditional uses across the region. Several species have already vanished from much of their historical range and are teetering on the edge of extinction. The listing in Appendix II of CITES means exporting countries must now ensure that trade is sustainable.

Hornbills are essential seed dispersers, shaping and sustaining Africa’s forests. Their distinctive breeding system, in which females and chicks are sealed inside tree cavities for safety, makes them extremely vulnerable. When males are killed during this period, entire nesting attempts collapse, leaving females and young to starve, trapped inside the tree.

The nations at CITES also adopted proposals to list six species of Sporophila songbirds. The critically imperiled great-billed seed-finch, Sporophila maximiliani, received the highest level of protection under Appendix I with a full ban on trade. Five additional seed-finches will be included in Appendix II with trade controls. Persistent global demand for these birds in the songbird trade has pushed the great-billed seed-finch dangerously close to extinction. The birds are used in songbird competitions and as pets.

“Globally, the illegal and unsustainable trade in birds is accelerating, threatening more species every year,” Shepherd said. “Listing these birds is a vital first step, but we’ll need effective enforcement and strong public support to make the protections meaningful.”