The United States Fish and Wildlife Service has identified 23 species it says are now extinct. 美国鱼类和野生动物服务局已经确定了23种它已经灭绝的物种。 

The agency released a list Wednesday that includes 11 birds, eight freshwater mussels, two species of fish, a bat and a plant. Most of the species had been found in states in the southeastern U.S. Eleven species lived in Hawaii or Guam. 该机构周三发布了一份清单，其中包括11只鸟类，八个淡水贻贝，两种鱼，一只蝙蝠和一只植物。 大部分物种都在美国东南部的11种居住在夏威夷或关岛的州中。

Perhaps the best known species on the list is the ivory-billed woodpecker. There had been unconfirmed sightings of the bird over the past 20 years. That led to search operations in parts of Arkansas, Louisiana, Mississippi and Florida. But none of the woodpeckers were found. 名单上最著名的物种也许是象牙嘴啄木鸟。 在过去的20年中，鸟类尚未得到证实。 这导致了阿肯色州，路易斯安那州，密西西比州和佛罗里达部分的搜索行动。 但是找不到啄木鸟。 

Other species on the list had only been identified in the wild a few times and never seen again. One example is the flat pigtoe, a freshwater mussel found in Alabama and Mississippi. In such cases, the species likely started disappearing shortly after being discovered. 名单上的其他物种仅在野外发现了几次，再也没有见过。 一个例子是扁平的玉米饼，这是在阿拉巴马州和密西西比州发现的淡水贻贝。 在这种情况下，该物种很可能在被发现后不久就开始消失。

In declaring a species extinct, the Fish and Wildlife Service removes it from its Endangered Species Act (ESA). The purpose of the ESA is to call attention to species with the greatest need for protection. 在宣布一种物种灭绝的过程中，鱼类和野生动植物服务将其从其濒危物种法（ESA）中删除。 ESA的目的是引起人们对保护需求最大的物种的关注。 

The agency said the identifications came after officials carried out “rigorous” investigations based on “the best available science for each of these species.” The declarations will become final after a three-month public comment period. 该机构表示，这些识别是在官员们根据“这些物种中最佳科学的最佳科学”进行“严格”调查之后进行的。 在一个三个月的公开评论期之后，声明将成为最终的。 

All 23 species were thought to have at least a small chance of survival when added to the ESA list. Only 11 species have been previously removed because of extinction in the nearly half-century since the ESA was signed into law. 当将所有23种物种添加到ESA列表中时，所有23种至少都有很小的生存机会。 由于ESA被签署为法律以来，由于近半个世纪的灭绝，以前仅删除了11种。