Generalists rarely are considered for classical biocontrol because their broad feeding habits are expected to make non-target impacts inevitable. This assumes an increase in overall ecological risk with increasing number of feeding connections. With the goal of inspiring fresh consideration of the safety of exotic biocontrol agents for classical biocontrol, we present a selective review of the impacts of nine particularly-well-studied exotic natural enemies ranging from relative specialists to generalists. Surprisingly, non-target effects could be particularly strong for relative specialists that attacked just a few natives, but were often widespread but weak for the broadest generalists. This appeared to reflect relatively strong apparent competition and density-dependence for the narrow feeders, versus broadly diffuse net effects for the broader feeders. Overall, we suggest a sole focus on specialists in classical biocontrol might be an unreliable means to reduce ecological risk. Additional research is needed to fully compare the net direct and indirect effects of generalists and specialists across food webs, following classical biocontrol releases.

多才多艺的人很少被视为经典的生物防治方法，因为他们的广泛进食习惯有望使非目标性影响不可避免。假定随着饲养连接数量的增加，总体生态风险也会增加。为了启发人们重新考虑外来生物防治剂在经典生物防治中的安全性，我们对九种经过特别研究的外来自然敌人（从相关专家到通才）的影响进行了选择性综述。出乎意料的是，对于只攻击少数几个本地人的相对专家而言，非目标的影响可能会特别强，但对于最广泛的通才来说，这种影响通常很普遍，但较弱。这似乎反映了狭窄喂食器的相对强烈的表观竞争和密度依赖性，与更广泛的馈线的广泛分散净效应相比。总体而言，我们建议仅关注经典生物防治专家可能是降低生态风险的不可靠方法。在经典的生物防治措施发布之后，还需要进行其他研究来全面比较通才和专家在整个食物网上的直接和间接净作用。