Cherry Birch Recovery Strategy Executive Summary
This document provides a summary of the recovery strategy for the Cherry Birch, which advises the ministry on ways to ensure healthy numbers of the species return to Ontario.
Prepared by Christopher Zoladeski and Kate Hayes
Cherry Birch is a medium-sized, deciduous tree, usually growing on moist, well-drained soils. There appears to be only one wild population in Canada, located in the Niagara Region of Ontario, west of St. Catharines. Despite several focused searches in natural habitats along the Lake Ontario shoreline and Niagara River valley, no additional Cherry Birch specimens have been found in this region. The nearest other population is located approximately 70 km east in New York State.
Cherry Birch is widespread in the eastern United States. Its range extends from the states of Maine, New Hampshire and Vermont, south through the Appalachian Mountains to northern Alabama and Georgia, with disjunct occurrences in Mississippi and western Kentucky.
In Ontario, Cherry Birch is thought to have always been a minor component of forests at its historical and extant locations; nonetheless, its population has declined by 72%, from 50 trees observed in 1967 to 14 trees in 2005. Presently, there are only two sites, in proximity to each other, together harbouring probably not more than 18 individuals, nearly half of them being seedlings planted on a residential lawn. At the location where young trees grow within a natural forest habitat, the individuals appear healthy and produce seeds, but the level of reproductive success is unknown.
Habitat loss and degradation, including shoreline erosion, are believed to be the greatest threat to the species' survival. The apparent inability of Cherry Birch to establish at new sites may be caused by genetic depression and loss of fitness, caused by inbreeding and long isolation from the main distribution range.
The recovery goal is to ensure continued persistence of Cherry Birch at known sites in Ontario with no further decline in population size in the short-term and an increase in population size in the long-term. The protection and recovery objectives are:
- maintain the extant population of mature trees with the number of individuals stable or increasing;
- monitor planted Cherry Birch saplings and seedlings, and investigate possibilities of transfer to natural habitat;
- identify, protect and restore potential suitable habitats and reintroduce populations where possible, particularly at historical sites; and
- gain an understanding of habitat requirements, genetics, life history and population trends.
The only major recovery action carried out recently has been the planting of several dozen seedlings, grown from seeds collected on-site within a residential lawn and adjacent forest.
The proposed approaches to recover Cherry Birch, in addition to stewardship, include monitoring the population of mature trees, monitoring planted seedlings, exploring the feasibility of transplanting the seedlings to nearby natural habitats, growing additional seedling stock at nursery facilities and initiating rigorous research of Cherry Birch genetics, population biology and habitat requirements.
It appears that the species may not require large habitat patches for its preservation however the minimum habitat size requirements are unknown at present. As a conservative approach, it is recommended that habitat patches of the specific forest type where naturally established Cherry Birch already grows as a tree or sapling, be prescribed as habitat in a habitat regulation.