An examination of the distribution, habitat and genetic and physical characteristics of Fundulus diaphanus, the banded killifish, in Newfoundland and Labrador

Abstract

The banded killifish, Fundulus diaphanus, belongs to the family Fundulidae. One of two fundulids in Newfoundland (the other is the brackish water dweller, the mummichog, F. heteroclitus ), the banded killifish inhabits freshwater habitats. Located in 7 known localities across insular Newfoundland, most coastal in nature, the distribution of F. diaphanus is scattered and disjunct. The Indian Bay population record is an eastern range extension from the previous such record at Freshwater Pond on the Burin Peninsula and is the only northeast insular record of the species. While suitable habitat, generally described as the sandy or muddy shallows of freshwater lakes with abundant submerged aquatic vegetation, is fairly common, interior lakes may be unreachable due to steep river gradients. Preliminary enzymatic electrophoretic analysis indicated very little variation among the Newfoundland populations and a mainland population near the type locality. Classic morphometric analysis illustrated slight variations among populations but few consistent trends in variation. Previously designated as vulnerable (special concern) in 1989 by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), this project culminated with a re-designation of the special concern status in May 2003 after a review of the first status report compiled solely on the Newfoundland populations of the species. While the current analysis provided little evidence to treat the Newfoundland populations as a separate species or subspecies, the disjointed distribution and few confirmed localities where they occur are causes for concern and were key contributors to the species being designated as of special concern in Newfoundland.