Compensation policies seek to counterbalance biodiversity losses caused by development; however, their effectiveness is rarely tested. We examined U.S. Species Conservation Banks (SCBs) in California, a compensation program initiated 30 years ago. We quantified the effect of 59 SCBs (15,350 ha) on habitat extent using statistical matching methods. SCBs averted a small, yet significant, amount of habitat loss (62 ha) between 2001 and 2011. However, unexpectedly, SCBs also averted significant habitat gains (1,424 ha). It is not possible to determine if losses averted by SCBs equaled losses caused by development for which credits were sold (because records of the latter do not exist), but estimated averted gains were 35 times greater than averted losses. To improve practice, SCBs must be designed to achieve outcomes that are additional and avoid crowding out other programs incentivizing statewide conservation goals.

中文翻译：

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量化美国物种保护银行的栖息地损失和收益，以改善补偿政策并避免不良结果

补偿政策力求抵消发展引起的生物多样性损失；但是，它们的有效性很少得到测试。我们研究了加利福尼亚州的美国物种保护银行（SCB），这是30年前启动的一项补偿计划。我们使用统计匹配方法量化了59个SCB（15,350公顷）对栖息地范围的影响。在2001年至2011年之间，SCB避免了少量但显着的生境丧失（62公顷）。但是，出乎意料的是，SCB也避免了显着的生境增加（1,424公顷）。无法确定渣打银行避免的损失是否等于出售信贷所产生的发展所造成的损失（因为后者的记录不存在），但估计的避免收益是避免损失的35倍。为了提高实践水平，