逆戟鲸或虎鲸具有世界性分布，并且已经记录或建议了几个不同的种群或类型。三到五种类型的逆戟鲸可能截然不同，足以被视为不同的种族、亚种，甚至可能是物种（参见物种问题）。iuCn在 2008年报告说，“该属的分类学显然需要重新审视，很可能o. orca将在未来几年内分裂成许多不同的物种或至少是亚种。”尽管不同虎鲸群的生态独特性存在很大差异，这使得简单的类型区分变得复杂。长期以来，人们认为不同地区的食哺乳动物虎鲸可能是密切相关，但基因检测驳斥了这一假设。
北部海域
北太平洋
1970年代和 80年代加拿大和美国西海岸的研究确定了以下三种类型：
驻留（食鱼）逆戟鲸：弯曲的背鳍是驻留雌性的典型特征。
居民：这些是东北太平洋沿岸水域中最常见的三种种群。居民的饮食主要包括鱼类，有时还包括鱿鱼，他们生活在称为豆荚的复杂而有凝聚力的家庭群体中。女性居民的特征是具有圆形的背鳍尖端，终止于尖角。他们始终访问相同的区域。不列颠哥伦比亚省和华盛顿常驻种群是世界上研究最深入的海洋哺乳动物之一。常驻虎鲸可分为至少三个不同的社区；阿拉斯加北部、南部和南部.阿拉斯加南部常驻虎鲸分布于阿拉斯加东南部至科迪亚克群岛，数量超过 700只。这些鲸鱼由两个杂交氏族组成，它们以声音叫声区分，并且它们的活动范围重叠。北部居民社区居住在从阿拉斯加东南部到温哥华岛的沿海和内陆水域。它由三个部族和16个群组成，共有 300多头逆戟鲸。南部居民社区通常栖息在不列颠哥伦比亚省南部和华盛顿的内陆水域，但也可以在温哥华岛、华盛顿、俄勒冈和加利福尼亚的外海发现。它们由一个氏族和三个豆荚组成，数量不到 80只，被列为濒危物种。
transient or Biggs：这些逆戟鲸的饮食几乎完全由海洋哺乳动物组成.他们和居民住在同一地区，但两人互相避开。暂住者通常以小团体形式旅行，通常由两到六只动物组成，并且与居民相比，它们的家庭纽带不那么牢固。瞬变以较少变化和不太复杂的方言发声。与居民相比，雌性瞬变的特征是更多的三角形和尖背鳍。背鳍周围的灰色或白色区域，被称为“马鞍斑”，在居民身上通常含有一些黑色。然而，瞬变的马鞍斑块是实心的且均匀的灰色。瞬变沿海岸广泛漫游；在阿拉斯加南部和加利福尼亚州都发现了一些个体。瞬态也被称为Biggs orca以纪念鲸鱼学家 ic testing has refuted this hypothesis.
northern waters
north pacific
research off the west coast of Canada and the united states in the 1970s and 1980s identified the following three types:
resident (fish-eating) orcas: the curved dorsal fins are typical of resident feurs froasional sightings of larger groups of up to 200. Little is known about their habits， but they are genetically distinct frour off the galapagos islands. orcas sighted in hawaiian waters ur throughout the waters of Australia， new zealand and papua new guinea. they are sighted year round in new zealand waters， while off Australia， they are seasonally concentrated off the northwest， in the inshore waters of ningaloo reef， and the southwest， at the Breic evidence shows that the orcas of new zealand， and northwest and southwest Australia form three distinct populations. new zealand orcas mainly prey on sharks and rays.
Antarctic
Around 25，000 orcas are estimated around the Antarctic， and four types have been documented. two dwarf species， named orcinus nanus and orcinus glacialis， were described during the 1980s by soviet researchers， but most cetacean researchers are skeptical about their status， and linking these directly to the types described below is difficult.
some examples of variations in orcas
type A or Antarctic orcas look like a “typical“ orca， a large， black-and-white form with a medium-sized white eye patch， living in open water and feeding mostly on minke whales.
type B1 or pack ice orcas are smaller than type A. it has a large white eye patch. most of the dark parts of its body are medium grey instead of black， although it has a dark grey patch called a “dorsal cape“ stretching back from its forehead to just behind its dorsal fin. the white areas are stained slightly yellow. it feeds mostly on seals. type B1 orca are abundant between Adelaide island and the mainland Antarctic peninsula.
type B2 or gerlache orcas are morphologically similar to type B1， but smaller. this ecotype has been recorded feeding on penguins and seals， and is often found in the gerlache strait.
type C or ross sea orcas are the smallest ecotype and live in larger groups than the others. its eye patch is distinctively slanted forwards， rather than parallel to the body axis. Like type B， it is primarily white and medium grey， with a dark grey dorsal cape and yellow-tinged patches. its only observed prey is the Antarctic cod.
type d or sub-Antarctic orcas were first identified based on photographs of a 1955 mass stranding in new zealand and six at-sea sightings since 2004. the first video record of this type was made in 2014 between the kerguelen and Crozet islands， and again in 2017 off the coast of Cape horn， Chile. it is recognizable by its small white eye patch， narrower and shorter than usual dorsal fin， bulbous head (similar to a pilot whale)， and smaller teeth. its geographic range appears to be circumglobal in sub-Antarctic waters between latitudes 40°s and 60°s. Although its diet is not determined， it likely includes fish， as determined by photographs around longline vessels， where type d orcas appeared to be preying on patagonian toothfish (dissostichus eleginoides).
types B and C live close to the ice， and diatoms in these waters may be responsible for the yellowish colouring of both types. mitochondrial dnA sequences support the theory that these are recently diverged separate species. more recently， plete mitochondrial sequencing indicates the types B and C be recognized as distinct species， as should the north pacific transients， leaving the others as subspecies pending additional data. Advanced methods that sequenced the entire mitochondrial genome revealed systematic differences in dnA between different populations. A 2019 study of type d orcas also found them to be distinct from other populations and possibly even a unique species.