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What is an Important Bird Area?
An
Important Bird Area (IBA)
is a site providing essential
habitat for one or more species
of breeding or non-breeding
birds. These sites may contain
threatened species, endemic
species, species representative
of a biome, or highly exceptional
concentrations of birds.
The
goals of the Canadian IBA
program are to:
- identify a network of sites that conserve the natural diversity of Canadian bird species;
- ensure the conservation of sites through partnerships of local stakeholders who develop and implement appropriate on-the-ground conservation plans.
This plan helps direct and shape stewardship initiatives that are being planned by the South Okanagan Similkameen Conservation Program such that Yellow-breasted Chats are included in these initiatives.
The
Osoyoos Oxbows IBA
The core of the Osoyoos Oxbows IBA (CABC261N) encompasses the South Okanagan Wildlife Management Area (SOWMA). Presently the riparian areas of the IBA support 20% of the BC population of Yellow-breasted Chats; a population that is listed as critically imperilled in BC and nationally threatened. Other noteworthy riparian species that are present at this site include Western Screech Owl and Lewis's Woodpecker. The upland portions of the IBA are also home to a range of other provincially significant species including Lark Sparrow, Grasshopper Sparrow, and Bobolink. Several provincially and nationally significant mammal and herptile species also occur within the IBA. While the IBA is a core area for Yellow-breasted Chat conservation, it is widely acknowledged that for this species to persist in BC, conservation activity will have to occur throughout its historical range.
Why
the Yellow-breasted Chat deserves
conservation attention?
It is widely believed that the BC population of Yellow-breasted Chats is being slowly reduced through habitat destruction and as a result, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) has designated this population as an endangered species. The construction of dykes and canals to control flooding is one of the main causes of the loss of suitable Yellow-breasted Chat habitat. In addition, the development (clearing) of the valley bottoms of South Okanagan and Similkameen Valleys for agriculture, orchards, and urban development has also resulted in a significant decrease in the availability of suitable riparian habitat. The maintenance of the current population, let alone restoring it to its historical level, is dependent on a number of factors including stewardship on private lands, the alteration of management practices on provincial Crown land, including the SOWMA, and BC Provincial Parks, and habitat acquisition.
Current
Conservation Strategies
Within the IBA the management of the SOWMA is ongoing. After its establishment, parts of the riparian woodlands have been fenced to exclude cattle. In addition, Ducks Unlimited Canada and Ministry of Environment, Lands, and Parks (MELP) worked together on a major re-flooding project to restore some water flow to the marshes and oxbows in 1983. Other initiatives have included fencing, weed control and the installation of interpretative signs. An active riparian stewardship program, initiated in 1997 in by MELP known as the Riparian Restoration of Oxbows in the South Okanagan has worked with interested landowners primarily outside the bounds of the Wildlife Area. In other areas within the historic range of Yellow-breasted Chats, the South Okanagan-Similkameen Conservation Program, a multi-partner initiative of the federal and provincial governments and 17 non-government, conservation and community groups is embarking upon a program to conserve the biodiversity of South Okanagan-Similkameen's habitat and to protect its species at risk.
Conservation
Goals and Objectives
The goals of this conservation plan are twofold. First, this conservation plan will act as a means by which to help direct and shape stewardship initiatives that are being planned by the South Okanagan Similkameen Conservation Program. It is also hoped that the IBA program in conjunction with Partners in Flight (PIF) can further augment co-operative ventures with local biologists, conservation groups and First Nations groups in the region.
The following specific goals and objectives have been established for the Osoyoos Oxbows IBA and associated areas.
Strategic
planning. Effective
Yellow-breasted Chat management
will require the Ministry
of Forests and the Ministry
of Environment, Lands, and
Parks to work closely with
grazing leaseholders on the
crown lands of the IBA in
order to begin mitigation
work that may be necessary.
In addition, a Chat/riparian
bird-working group should
be formed to provide input
to stewardship programs and
to continue the work that
was initiated by Partners
in Flight.
Enhancement/protection.
One of the key components
of the conservation of Yellow-breasted
Chats in the South Okanagan
and Similkameen Valleys will
be the reduction of human
population impacts on Chat
productivity and survivorship
by protecting known nest sites,
and the enhancement of potential,
suitable and degraded habitats.
Outreach
and education. Community
outreach is an important component
of Yellow-breasted Chat conservation.
Outreach and education should
occur on a number of different
fronts including: the development
of a demonstration site accessible
to the public; the production
of suitable educational materials
that describes Yellow-breasted
Chat biology and habitat needs;
the communication of habitat
needs, research results and
enhancement trials to both
stewardship groups and the
general public; and the involvement
of the public involvement
with ongoing song bird monitoring
Research.
There are two levels of research
that should be considered.
On a coarse level, there is
a need for an up-to-date accounting
of the distribution and abundance
of Yellow-breasted Chats in
South Okanagan and Similkameen
Valleys. On a fine scale,
research questions that could
be addressed should include
an assessment of habitat variables
at know Chat sites; an examination
of habitat use by Chats; and
assessment of the nesting/fledging
success (productivity and
survivorship); and an assessment
of cowbird parasitism.
Monitoring.
A long-term monitoring program
is necessary to track the
status of Yellow-breasted
Chats and other riparian birds,
to fully ascertain the efficacy
of habitat enhancement efforts,
and to continually assess
the proper operation of enhancement
structures such as fences
and alternate water sources.
INTRODUCTION
Birds are key components in Canada’s ecosystems and bird populations are often used as indicators of overall ecosystem health. The conservation of an area to benefit bird life will also conserve other plants and animals present. The loss and fragmentation of habitat throughout the Americas over the last several decades has resulted in measurable population declines in many bird species in Canada. The future of Canadian wildlife depends on our commitment to provide an adequate amount of good quality habitat throughout their ranges.
In the South Okanagan and Similkameen Valleys in southern BC, the numbers of Yellow-breasted Chats (Icteria virens auricollis) have decreased over time (Cadman and Page 1994) to the point where the BC population is considered at risk of being extirpated. The Yellow-breasted Chat is Red Listed (under consideration for Threatened or Endangered Status) in British Columbia and the BC population has been listed as Endangered, by the Committee on the Status of Endangered Wildlife in Canada. The decrease in numbers of this species is linked to the precipitous loss, or degradation of riparian habitat due to flood control, farming, ranching, and urban sprawl. Only 15% of the original riparian habitat remains in the South Okanagan (Sarell 1990). The persistence of the current population is dependent on a number of factors including: stewardship on private land, First Nations Reserve Lands, alteration of management practices on Crown Land (including BC Parks), and on the acquisition of some of the remaining private land. It is believed that the BC population of Yellow-breasted Chats can be maintained at present levels if, and only if, most of the riparian habitat in which it currently breeds is protected through stewardship and acquisition (Dyer, pers. comm.). Restoration of the Yellow-breasted Chat population to historical levels in BC will require the restoration of a substantial portion of the currently unsuitable or degraded riparian habitat in the region.
Presently, the Osoyoos Oxbows IBA encompasses those lands that are under the jurisdiction of either the Ministry of Environment, BC Parks, or The Nature Trust within the bounds of the South Okanagan Wildlife Management Area (SOWMA) and presently supports a significant proportion (>20%) of the BC population of Yellow-breasted Chats. While the IBA is a core area for Yellow-breasted Chat conservation, it is widely acknowledged that for this species to persist in BC, conservation activity will have to occur throughout its historical range. In order for this to happen both short-term and long-term goals have been established. The short-term goal is to maintain the current population by maintaining and enhancing existing occupied habitat. The second, more long-term goal is to recover the population by restoring 25% of the historic habitat in the region. These goals will be accomplished in numerous ways. First, this conservation plan will act as a means by which to help direct and shape stewardship initiatives that are being planned by the South Okanagan Similkameen Conservation Program. It is also hoped that the IBA program in conjunction with Partners in Flight (PIF) can further augment co-operative ventures with local biologists, conservation groups and First Nations groups in the region. To this end the primary goal of the IBA program in the South Okanagan is to help direct and shape stewardship initiatives that are being planned by the South Okanagan - Similkameen Conservation Program.
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