The Morrison Creek Lamprey Enigma

Morrison Creek lamprey (Lampetra richardsoni variety marifuga) is found in Morrison Creek, Vancouver Island. It is the only known representation of an intermediate phase between parasitic and non-parasitic lamprey. It is listed as endangered and requiring protection, but  studies have shown a possible decrease in abundance of >90% over the past 25 years. DNA analysis of Morrison Creek lamprey and western brook lamprey (L. richardsoni) in Morrison Creek indicated  they were indistinguishable. The same study showed that the two types differed from western brook lamprey and the river lamprey (L. ayresii) from other locations. To protect  Morrison Creek lamprey, it will be necessary to protect the aggregate of all Lampetra species in Morrison Creek, becoming a taxonomic issue. The taxonomy of the Morrison Creek lamprey is difficult, but  a taxonomic designation is needed to accommodate the difference in life histories of the two types in Morrison Creek and the DNA difference between these two types and either L. ayresii or L. richardsoni. The dilemma is that because the DNA variation among western brook lamprey is poorly understood, it is not possible to decide on the taxonomy of the two types in Morrison Creek despite the need for immediate protection.