Heart-leaved Plantain Recovery Strategy Executive Summary
This document provides a summary of the management plan for Heart-leaved Plantain, a species of special concern. It advises the ministry on ways to ensure healthy numbers of the species return to Ontario.
Prepared by Jarmo V. Jalava and John D. Ambrose
The Heart-leaved Plantain (Plantago cordata) is a perennial herb that was first designated endangered in Ontario in 1985 because there are only two extant populations and they are limited by narrow habitat tolerance and ongoing habitat degradation. The global range originally extended across North America from Ohio, Ontario, Michigan and Minnesota, south to the southeastern United States, but the species is now extremely localized. The Canadian distribution has been reduced from seven historical populations to two extant locations near southern Lake Huron.
The extant Ontario Heart-leaved Plantain populations are found in rocky or gravely calcareous beds of shallow, slow moving clear streams or wet depressions. These streams or depressions are found in and shaded by relatively undisturbed low wet deciduous forests where ephemeral creeks flow in the spring and after heavy rains. Moisture is generally always present above or just below the soil surface. The species is limited by its specialized habitat requirements, the dynamic nature and limited availability of its habitat and its low reproductive output, high seedling mortality rate, limited dispersal ability and low genetic variation. Ontario populations are potentially threatened by removal of riparian vegetation, hydrological changes, degraded water quality, tree harvesting, munitions removal from a former military training area, collection for food and medicinal uses, invasive plant species and herbivory by invertebrates.
The recovery goal is to recover a self-sustaining, viable population of Heart-leaved Plantain in Ontario. This will involve population viability analyses to determine if and the degree to which extant populations need to be enhanced, as well as the number and extent of additional populations that will need to be established in the species' historical range in southern Ontario. In order to meet this goal, the following protection and recovery objectives are recommended.
- Protect and manage habitat at extant sites in Ontario.
- Determine the size and number of extant sites (area of occupancy and area of extent), site quality, population health and population trends through inventory and regular monitoring.
- Address key knowledge gaps relating to minimum viable population size, habitat requirements and prioritization of threats.
- Where feasible, improve the viability of Heart-leaved Plantain in Ontario by establishing populations at historical and other sites where suitable recovery habitat exists or can be restored.
- Promote awareness and stewardship of Heart-leaved Plantain to First Nations, land managers, private landowners, municipalities and other key stakeholders.
It is recommended that the area occupied by the plants be prescribed as habitat in a regulation, as well as an area of habitat surrounding the occupied area that is extensive enough to protect water quality and essential hydrological processes, allow for potential dispersal and population expansion, and maintain necessary moisture and light regimes. Specifically, the area prescribed should be a composite area delineated using the following three criteria: (i) a buffer of 120 m from the outer limits of a population; (ii) a minimum buffer of 30 m along the watercourse and its tributaries upstream from a population; and (iii) the limit of the Ecological Land Classification community (ecosite) within which a population occurs.
Although historical sites were probably extirpated primarily due to habitat loss, there nevertheless appears to be suitable unoccupied habitat within its range in Ontario. It is therefore recommended that the habitat regulation be flexible enough to include sites for which introduction or reintroduction is planned. It should be noted that the species may spread through the dispersal of seeds or propagules downstream during flood events in the riparian habitats it occupies. The habitat regulation should therefore also allow for the inclusion of newly colonized sites. It is also recommended that populations cultivated for domestic or medicinal uses be excluded from the habitat regulation.