Sharp-tails Plus Foundation Inc

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1 Sharp-tails Plus Foundation Inc Habitat Information This paper describes the ideal habitat for Manitoba Sharp-tailed Grouse. However, there are few ideal habitats for any species and a worthy goal can be to improve conditions wherever possible knowing that the ideal may never be attained. Also, Sharp-tailed Grouse are mobile under large areas seasonally and that may bring into play neighboring property. Nevertheless, there are many things we can do to enhance local habitat. Our goal is to help make these locations as Sharp-tailed Grouse friendly as possible. In North America there are twelve species of what are considered prairie grouse (American Ornithologists Union 1998). The species resident to Manitoba is the Sharp-tailed Grouse (Tympanuchus phasianellus). The NRCS (National Resource Conservation Service) list three sub species present in Manitoba (southwest Tp jamesi), (south Tp campestris), and (north Tp phasianellus). Not only do Sharp-tailed Grouse require very specific habitat but they require different types depending on season and activity. The following examines needs relative to breeding sites, nesting sites, brood raising sites and winter sites. It also details anthropogenic influence (human), and predation issues. Many of these issues we can influence. The key is to realize perfection of sites may seldom be attained but improvement will almost always be possible. Page 1

2 The following describes in detail various Sharp-tailed Grouse habitat needs: Breeding Sites: Sharp-tailed Grouse are a lekking species ie dancing as opposed to certain other prairie grouse whose breeding space is called booming grounds. Our grouse s spectacular breeding dance is perhaps one of its attributes that humans find most endearing. Breeding or lek sites are preferred to be slightly elevated knolls having short or sparse vegetation. Mature trees in proximity that offer avian predators a vantage point may deter the use of leks. The same sites are used year after year if they do not become excessively altered or disturbed. Usually the males attend these sites in early winter (about mid-november) but no breeding occurs at this time. At winter s breakup (around mid April) the birds attend for the mating ritual. Usually they arrive thirty to sixty minutes before sunrise and stay for two to three hours. The dominant males dance in the center of the group with the subordinate males on the outside. Females arrive after sunrise and almost always mate with one of the dominant males. The size of a lek can be as small as a house or as large as a baseball diamond. Anywhere from two to as many as thirty five males may attend. The sites are extremely sensitive to disturbance late winter and early spring. Having a lek site on property is a jewel. Most agree that lek sites should be disturbed as infrequently as possible. Lek sites can be jeopardized in both late winter and early spring by many factors including but not restricted to: inappropriate vegetation coverage, predators, recreational vehicle traffic, avian vantage points, and other anthropogenic (human) conditions. Many of these detractions are solvable through our habitat management or education programs. Nesting Sites: Nesting site condition is one of the most important determinants in sharp-tail population. Nests of prairie grouse are bowl shaped depressions in the ground which the hen lines with feathers, dried grass, leaves and/or small twigs. Nesting starts with the breeding cycle usually in late April or early May. Sharp-tailed Grouse need good stands of residual or left over standing vegetation from the previous year for their initial nesting attempt. Prescribed burns that remove this nesting cover are detrimental to this coverage protection. Nest sites are often on flat land or land with a north to northeast slope. The nests are usually within a kilometer to two of the lek site. The nests average about twelve eggs which hatch simultaneously even though they are laid at a rate of about one per day. Adequate cover to conceal nests is crucial. Extensive areas of nesting habitat are necessary to prevent nest predators concentrating their searches. It is important therefore to have flock size proportionate to the size of the nesting site. Page 2

3 Brood sites: This is the second of the two most important population determinants. The brood site conditions are different from the nesting sites in that they require a more heterogeneous mix. The habitat must provide prairie grouse chicks with concealment from predators, an invertebrate (insect) food source, plus loafing and resting areas open enough to permit travel by the chicks, but also offer midday shade. The brood remains in the vicinity of the nest for approximately three weeks. Chicks can fly short distances by the time they are seven to ten days old. The critical period for chicks is from hatching to brood breakup and dispersal in early fall. High quality brood habitat includes forbs (herbaceous flowering plants) to support an insect population, mixed grasses and a scattering of shrubs. Anthropogenic influence: Anthropogenic activity refers to human created influence that negatively impacts the birds. Sharp-tailed Grouse are particularly sensitive to this influence in early winter (mid November) when the males visit the lek sites, in early spring (April) during breeding at the lek sites, nesting, and brood rearing periods. Wherever possible non-farming vehicles should be restricted at these crucial times and locations. The late fall harvest of mature birds will not have a detrimental influence on population if it is managed properly. Culling birds in the fall can have either a positive or negative affect depending on circumstances. If a flock is too large in proportion to the size of the nesting area then the site invites undue predation. Nests must be spread out over a large area to avoid predators concentrating their search. A flock population is best balanced if it is proportionate to the nesting site size. On the other hand harvesting birds under a non-managed scenario can be detrimental. Bird harvest limits do not solve the issue of several hunting groups attending the same location even though each group may be restricting their bag limit to below the allowable. The most effective management continues to be access control from the land owner based on local bird population and nesting habitat issues. Page 3

4 Predation issues: Predation may be the biggest source of mortality. Sharptailed Grouse are particularly prone to predation because of the following traits: (a) ground nesting (b) large broods that are difficult to control (c) predictable lekking behavior. Predators particularly during nesting include coyotes, skunks, great horned owls, marsh hawks, ground squirrels, magpies, crows and ravens. Adequate nesting and brood cover is crucial in keeping predation under control. Winter sites: Winter habitats for Sharp-tailed Grouse are usually within one to five kilometers of breeding sites. Riparian areas or areas with deciduous trees and shrubs, in addition to forbs and grasses provide desired winter habitat. Areas of exposed or snow free cropland or alfalfa are also ideal. However, crops are not essential winter habitat components. Most birds rely on feeding on aspen or willow buds in winter. Sharp-tailed Grouse will burrow in soft snow to escape predation. Province Wide Coordination As more Sharp-tailed Grouse habitat is lost the populations become isolated. Fragmented landscapes and resulting isolated populations are bad news. Fragmentation holds several disadvantages but perhaps the most serious is loss of genetic diversity. Several studies have dealt with this issue and little of the information is encouraging. Sharp-tails Plus are engaged in a multi-year program to better understand where various Sharp-tailed Grouse populations are located in the province, what habitat they are using, and what habitats they have vacated. This will assist with developing broader land management programs and policies in Manitoba. The subjects of reconnecting sub-populations, translocating birds to aid genetic diversity goals, and adding or improving habitats through prescribed burns and brush rolling, are all expensive alternatives that will only receive consideration after appropriate population models are established. Sharp-tails Plus Inc will make use of the most current state of the art satellite mapping to help define where favorable bird habitat exists. Page 4

5 Managing Habitat Issues: Manitoba is made up of very diverse agricultural land use areas and ecosystems that the Sharp-tailed Grouse use as home. Sharp-tailed Grouse prefer some Manitoba locations over others. Many of our Sharp-tailed Grouse locations are found in grasslands, alfalfa and hedge rows, marsh edges, cropland slough bottoms, and northern meadows. Although these areas on the surface seem to be very different habitats, nevertheless they all possess the same common denominators that the birds seek for mating, nesting, brood rearing, and winter. Some of the most effective habitat management tools are the nonintrusive practices of land owners and land stewards. The large scale programs such as aspen control, relocating birds, and new habitat creation, are all important but no more important than the nonintrusive improvement of existing bird population conditions. The following is a short list of some of these somewhat nonintrusive practices that a land owner can put in place: Preserve favorable lek conditions through appropriate mowing and grazing practices. Remove avian predator vantage sites. This is often an attainable goal as lek sites are relatively small areas of the farm or ranch. Preserve nesting sites. Ideal sites are expansive in size with extensive cover. Sites that are too small for the flock invite predator concentration. Sites that have sparse cover offer inadequate predator protection. Where possible avoid cutting or burning grassland cover from the previous fall. Cropland slough bottoms offer excellent nesting conditions if not burnt in the fall. Preserve brood raising conditions. This is not an easy task. Chicks require a diverse landscape to run, play and hide in. Where appropriate, develop mowing practices that minimize chick mortality. Where possible avoid spraying for insects in or near brood raising locations. Remember that chicks need an insect food source for protein and insects thrive on herbaceous flowering plants. Real gains can be made where chick mortality is impacted. Remember that each hen lays about a dozen eggs and the chicks can fly short distances after about seven days from hatching. Page 5

6 Preserve winter sites. It is quite likely that the winter site of your flock is within nearby aspen cover. Preservation of marginal bush land can be a saving grace for the Sharp-tailed Grouse. Control adverse anthropogenic influence. Avoid undue lek site interference in both early winter onset and winter breakup. Unnecessary vehicular traffic into the bird populations should be avoided. Private land owners manage the harvesting of the birds on their land in fall hunting seasons. Flocks that are too large for the available nesting sites invite predator concentration. Conversely flocks can be overharvested if several hunting groups are attending a location and are not aware of the overall number of birds being taken. Flock size should be managed consistent with the available habitat. Consideration may be given in some situations to selective predator control. Some predators such as crows, skunks, foxes, and coyotes may be controlled under set conditions. Other predators such as hawks and owls may not be culled. Excessive predation by for example coyotes at the peak of a population cycle can prove to be extremely destructive to a Sharp-tailed Grouse population. Predator control depends very much on specific circumstances. Many have concluded that the best method of predator control is to manage the habitat coverage at nesting, brood raising, and winter sites. Report prepared by: W J Bill Burns June 2013