Birds of Prey are important components of an ecosystem for the reason of keeping prey populations stable and at a minimum (Cagnolo and Valladares 2009). Aiding as a tertiary predator they help maintain a healthy ecosystem. Species obtaining higher trophic levels are more susceptible to extinction because they feel vertical and horizontal effects on their populations, therefore, management for birds of prey in Neithercut woodland is of importance (Cagnolo and Valladares 2009). Neithercut is used as a learning tool for future biologist and others and should be a good representative for a strong ecosystem. Because of logging and habitat fragmentation many large birds of prey with large habitat needs have been displaced due to habitat degradation (Cagnolo and Valladares 2009). Four species of hawks are of conservation concern at Neithercut woodland in Clare County, Michigan: Northern Goshawk (Accipiter gentilis), Red-shouldered Hawk (Buteo lineatus), Northern Harrier (Circus cyaneus), and Sharp-shinned Hawk (Accipiter striatus). We propose a management plan to aid in the productivity of these four hawks at Neithercut Woodland and surrounding state.
Introduction and Species Background Information: Northern Goshawk
The northern goshawk (Accipiter gentilis) is a relatively large and reserved forest-dwelling hawk generally inhabiting more mature deciduous, coniferous, or mixed forest stand (Squires and Reynolds 1997). In the southern reaches of the U.S. nesting habitat for the goshawk is primarily ponderosa pine forests (Snyder and Snyder 1998). Goshawk breeding range occurs from Alaska south through the western U.S. and east across Canada and the Great Lakes region to the northern Atlantic coast (Squires and Reynolds 1997). These birds have been known to inhabit areas as far south as western central Mexico. Goshawk habitat, (aka. Breeding and foraging habitat), generally includes mature upland forests, but will occupy forest types with a mixture of mature deciduous and mature conifer trees with closed canopy cover (Michigan Natural Features Inventory 2007). Trees goshawks have been primarily associated with are: white pine (Pinus strobus), red pine (Pinus resinosa), and northern hardwoods (oaks, aspen hemlocks, ect.) These meandering migrant winters throughout its breeding range including on occasion the Great Plains and southeastern states; some individuals undergo short movements to lower elevations during winter, apparently in search of food (Squires and Reynolds 1997). While goshawks may migrate in search of food or suitable habitat for brooding purposes, the mean home range area for a goshawk encompasses an area of approximately 5146 ha for males and 3859 ha for females (Moser 2007).
Goshawks are well adapted for hunting in forests but also hunt open habitats. The Goshawk is a authoritative hunter capable of killing a variety of prey, including tree squirrels, hares, grouse, corvids, woodpeckers and large passerines such as American Robins (Turdus migratorius)(Squires and Reynolds 1997). The U.S. Fish and Wildlife Service have become aware of the fact that forest dwelling accipiter hawks are dependent more on prey availability within a forest. This prey availability is the then determined directly by the forest structure they inhabit. Seasonality changes within the goshawk range may lead to differential forage habitat during the breeding season than that of cold winter months (Drennan et al. 2003). Drennan (1997) noted in his study on goshawks that during their breeding season they did not select forests sites based simply on prey availability but instead, selected a habitat that represented a high canopy closure associated a large tree density averaging (>40.6 cm dbh). But apposing a study done by the Fish and Wildlife Service, as referenced in Anderson et. al. (2005) the yearly variability of nesting success and reproductive success tends to be characteristic of all goshawk populations and therefore is commonly associated with annual variation in weather and prey availability.
Goshawks on average produce two to three eggs during the months of March and April with most of the eggs generally hatching around May (Michigan Natural Features Inventory 2004). During this period of incubation, the female plays an important role in regulating nest temperatures and providing ample conditions for the hatching of the eggs. Fledging of the young usually occurs within 35-36 days of hatching, and from that point the fledglings are usually dependent on the parents for food resources for up to a total of 70-80 days (Michigan Natural Features Inventory 2004). Throughout this process goshawks both male and female tend to be highly territorial, fending off any unwanted intruders within the local areas of nesting habitat (Ottawa National Forest 2004).
The distribution within the state of Michigan, the northern goshawk is more commonly seen throughout the Northern Peninsula, and less prevalent in regards to the Lower Peninsula. This may be attributed to the presence of more contiguous landscape the Upper Peninsula has to offer compared to the southern Lower Peninsula. This landscape differentiation can be observed from the map produced from MNFI describing the occurrences from 1998-2007 (Figure 1). This assumption of occurrence can be reinforced from common knowledge of forest patterns seen throughout Michigan, all coinciding with more northern parts of the Lower Peninsula, and most of the mature forest landscapes covering the Upper Peninsula. Within the Neithercut area of Clare County, the number of occurrences of the northern goshawk <1 (Michigan Natural Features Inventory 2007). Refer to (Figure 2) for visual results of weighted goshawk occurrence within the state of Michigan.
Numerous species of amphibians, mammals, birds, and reptiles inhabit and are located within the Neithercut region (Table 1). Most importantly to the survival of the Northern Goshawk, the small to medium size mammals that are found within this area. The dependence of the Northern Goshawk on species such as ruffed grouse (Bonasa umbellus) and snowshoe hare (Lepus americanus) commonly account and are correlated with the species abundance and brood survival of the goshawk; all fluctuating on cyclic ten year period (Erdman et. al. 2007). Other species of forest dwelling raptors that inhabit Neithercut region may include the red tailed hawk (Buteo jamaicensis), the red shouldered hawk (Buteo lineatus), and the sharp shinned hawk (Accipter striatus) which may need be taken into account when determining density of other predators within the area, and their overall impact on the prey available or influence of competition for food and ultimately the survival of the goshawk.
Introduction and Species Background Information: Northern Harrier
A long-legged, long-tailed hawk of open grassland and marshes, the Northern Harrier forages by flying slowly low above the ground looking for small rodents. Average harrier length is 17-23 inches and wingspan averages 38-48 inches. It is one of the few raptors in which the sexes look quite different in both color and size. The male has a light gray back and hood and is white below with black outer primary feathers. The female is brown above and buff-colored with brown streaks below. Females are close to 50% heavier and 12.5 % larger than males (MacWhirter and Bildstein 1996). Juveniles are brown above and plain orange-brown below. Both adults and juveniles of both sexes have a characteristic white patch at the base of their tail. The average lifespan of a northern harrier in the wild is seven years (Brown and Amadon 1969).
While in flight, the harriers will fly close to the ground with only periodic heavy wing beats, gliding slowly over open habitats. Unlike other hawks, the Northern Harrier relies on its hearing as well as its vision to capture prey. The feathers of the face are stiff to help transmit sound, and it shows a pronounced "facial disk," much like that of an owl. This attribute provides exceptional auditory capabilities and assists in prey capture. When sounding an alarm or excited call, their vocalization has been described as “ke-ke-ke” or “chek-ek-chek-ek”(Brown and Amadon 1968).
The Northern Harrier feeds primarily on mice, other small mammals, frogs, reptiles, and small birds. It will, however, take larger prey, such as rabbits and ducks. It has been known to subdue large prey by drowning it. The diet of insects is mostly limited to those just young fledglings. The hunting habits seem to be determined by the closeness to the nest site, location and prey abundance.
Northern harriers winter in the United States as well as Central America and the Caribbean. For that reason, spring migration can vary from very short to very long distances. Usually by the end of March through the end of April, winter territories and communal roosts are discarded and spring voyage starts (MacWhirter and Bildstein 1996). During the spring migration, adult harriers arrive before juveniles and males arrive before the females to the breeding grounds (Hamerstrom 1969). After the nesting interlude, harriers will proceed back south starting from the third week of August through the third week of November.
The courtship between northern harriers has been termed “sky dance”. This ceremony involves sharp dives and spherical rolls by males to entice a female mate. Even though pairs can mate in consecutive years, these harriers do not mate for life. Most male harriers are mated to one or two females at the same time. There have been instances where some males have paired with up to five mates in a season. The frequency of polygamy is related to the male versus female gender ratio on the breeding grounds (England 1989). The female is the one who initiates copulation.
Nest construction starts with both female and male transporting building materials but the female completes most of the actual building of the nest (Toland 1985). The harriers will nest on the ground in open fields or meadow, or over water on platforms of vegetation in cattail stands. Ground nests are well concealed by tall, dense vegetation, including living and residual grasses, or low shrubs. One advantage of wet nests might be that there are fewer predators that have access to them (Sealy 1967, Simmons and Smith 1985). The placement of these nests might also be because of the nearness to vole populations. Their nesting period ranges from the fourth week of April to third week of July.
Females incubate the eggs and brood the offspring, while the male provides the bulk of the food for his mates and their nestlings. The size of a clutch may vary between 2-10 eggs. The eggs are a light blue when laid then turn white after a few days. Usually one clutch per reproduction season is typical, but sometimes renesting will occur if the original nest is damaged or lost (Duebbert and Lokemoen 1977). The incubation period will last about 26-32 days (Breckenridge 1935). The young are born covered in white down, with their eyes open. The juvenile harriers will remain in or around the nest for another 30-35 days until they learn to manage flight (Hammond and Henry 1949).
Northern Harriers favor reasonably open habitats characterized by tall, dense vegetation. Some of the types of habitats are: wetlands, meadows, pastures, prairies, grasslands, croplands, and riparian woodlands. These suitable habitats are very important to this ground nesting raptor. This habitat must also be of a suitable size. In Washtenaw County, here in Michigan, the territories average about 640 acres (Craighead and Craighead 1969). Their hunting habits are established by the close range of the nest site and the location of abundant prey. Male harriers will expand their hunting areas farther from the nest unlike the females who hunt adjacent to the nest.
Northern harriers are actually divided into two recognized subspecies: C. c. hudsonius in North America and C. c. cyaneus (hen harrier) in Eurasia. In North America, the northern harriers breed south of the tundra in Alaska and throughout Canada, south to southern California east to southern Texas and across to northern Virginia (Hands et al. 1989.) During winter the range extends from southwestern Canada east to southern New England, south to California, Central America and the Caribbean.
In Michigan, northern harriers will breed all over the state as long as long as there is a suitable habitat found. Observed nesting grounds are recorded for 32 of Michigan’s Counties (Figure 3) (Brewer et al. 1991, Michigan Natural Features Inventory 2001). There are four areas that have been suggested as the highest monitor areas by the Michigan Breeding Bird Atlas. These areas include: 1) the Gladwin-Midland county area in the Lower Peninsula; 2) Dickinson, Menominee, and Delta counties in the south-land Upper Peninsula; 3) Schoolcraft, Mackinac, and Chippewa counties in the eastern Upper Peninsula; and 4) the Tuscola-Sanilac county area in the Thumb region (Brewer et al. 1991).
Introduction and Species Background Information: Sharp-shinned Hawk
The sharp-shinned hawk (Accipiter striatus) is the smallest of the North American accipiters. The sharp-shinned hawk has two distinct appearances over the course of its life. When immature, the sharp-shinned hawk has a brown back, a light gray head, and its ventral surface is a cream white color with red/brown longitudinal markings across its stomach. As an adult, the bird has a dark slate gray back and head, a heavily barred stomach, and white only under the tail. The bird also shares morphologies similar to that of other hawks: short hooked beak, rounded wings, grasping toes, and sharp talons. Sharp-shinned hawks show the greatest degree of sexual dimorphism of any North American bird, with the female being nearly 1/3 larger than males and nearly twice the weight (Hoffman et al., 1990). The average mass of an adult female is 172.4 g and 103.1 g for adult males (Powers, 1996). The wingspan of the females ranges from 58 to 65 cm and males range from 29 to 34 cm (U of M Museum of Zoology).
Sexual maturity of the sharp-shinned hawk typically is reached a little after 2 years of age. Due to their secretive behavior, very little is known about their mating behavior. However, they are known to have courtship flights and are believed to be monogamous (Bildstein and Meyer, 2000). Egg laying will start around May to mid-July. The eggs are laid on alternate days and the clutch size is usually around 4 or 5 eggs. Incubation will take 3 to 5 weeks and hatching will take about 2 days (Bent, 1961). While still in the nest, the young will fly around neighboring branches of the nest and then eventually neighboring trees to develop wing strength (Rompre, 2003). Fledging of the young birds occurs approximately 4 to 5 weeks after (Reynolds and Wight, 1978).
Predators of the sharp-shinned hawk consist of other birds of prey. Such birds include bald eagles, peregrine falcons, and northern goshawks (Bildstein and Meyer, 2000).
The diet of the sharp-shinned hawk consists primarily of songbirds but will occasionally prey on small mammals, bats, frogs, lizards, and snakes. Songbirds will consist of up to 91% of the bird’s diet with mammals consisting of 8%. (Joy et al., 1994). The birds have been commonly seen in urban areas foraging and hunting around bird feeders (Dunn and Tessaglia, 1994). The diet of the sharp-shinned hawk is known to have some economic impacts for humans. A negative impact that they have is that they prey upon songbirds that people like to see and game birds; which people like to hunt. However, they’re diet of songbirds also has a positive impact because they will also prey upon pest species such as European starlings and house sparrows.
The sharp-shinned hawk is an opportunistic hunter and will hunt from a perch, darting out from hiding to catch its prey. Using their long sharp talons, they will grab onto their prey using short bursts of high-speed flight to surprise their prey. Once the prey has been subdued, the sharp-shinned hawk will pluck its prey before eating it. The sharp-shinned hawk does not need to drink water because it obtains sufficient water supply from the prey they catch (Bildstein and Meyer, 2000).
Sharp-shinned hawks will nest in large forests consisting of conifer, deciduous, and mixed wood forests with a dense canopy so the nest will be hidden. The birds will typically build their nests near openings and grasslands where their prey is abundant and cover is sufficient (Reynolds et al., 1982). The nesting territory for sharp-shinned hawks ranges from about 0.25 to 0.5 miles (Delannoy and Cruz, 1988).
During migration, sharp-shinned hawks will use a variety of habitats that have a lot of vegetative cover, similar to that of their nesting habitats. The birds will tend to avoid large open areas where they can be seen easily and tend to migrate along ridgelines (Mueller and Berger, 1967). In the winter, the sharp-shinned hawks will spend a lot of time in lower elevation areas where cover and prey are abundant (Duncan, 1996).
Threats to the sharp-shinned hawk include habitat destruction, pesticides, and hunting. The most critical threat to sharp-shinned hawks is habitat destruction due to logging and habitat fragmentation. Logging and habitat fragmentation causes a loss of nesting trees for the birds which causes a decline in sharp-shinned hawk populations. This is not too much of a problem, however, since the sharp-shinned hawks can adapt well to human habitats. Bird feeders in urban areas are great feeding grounds for sharp-shinned hawks.
Pesticides from neighboring farms cause bioaccumulation in many hawk species and has caused an increase in fledgling mortality rates, thinning of egg shells, decrease in reproductive success, and respiration problems (Henny et al., 1973). Hunting is a minor problem and is commonly done by homeowners trying to protect the birds they want to see at their bird feeders (Bryant et al., 1936).
Introduction and Species Background Information: Red-shouldered Hawk
The red-shouldered hawk is a large buteo bird of prey. With a rusty looking breast, rusty ventral wing linings, and rusty colored shoulders their common name is obvious. These hawks also have about 5 to 6 white and black bands on their tail feathers. They have a black and white checkered pattern on their dorsal back side and a brownish head. They are distinguishable from their competitor the red-tailed hawk by the white and black banding and lack of red on their tail feathers. Red-shouldered hawks also show crescent-shaped translucent-like patterns on their outermost wing feathers.
The red-shouldered hawk’s call is a loud and persistent “kee-yer”. But using solely their call for presence or absence is frowned upon due to the fact that blue jays will mimic a red-shouldered hawk’s call. The females’ call is usually much lower pitched than males (Crocoll 2008). Red-shouldered hawks will call when a red-tailed hawk or a great horned owl are present and also during courtship. During nesting females and young will reply to playback recordings (Crocoll 2008). As well, Red-shouldered hawks show sexual dimorphism by females being larger, however their coloration is the similar.
The red-shouldered hawk generally returns to Michigan in late February to early March (Ebbers 1991). They arrive in pairs and create nests, if not re-occupying old nests, near water such as a swamp or pond (Cooper et al. 1999). Their nests consist of twigs, sticks, bark, dead leaves, feathers and are built in the crotch of trees about 35 to 40 feet off the ground (Ebbers 1989). They mate around mid-March and incubation of the eggs begins in late-March to April (Figure 4). Male and female both contribute to incubating the eggs, however the female usually does most (Palmer 1988). Incubation of the eggs is about 33 days with the young fledging in June and staying with the parents until the fall when they migrate (Craighead & Craighead 1956). At about two years of age the young are ready to reproduce (Smith 1988).
Red-shouldered hawks eat a wide variety of prey: small mammals, reptiles, amphibians, sometimes small birds, and in some regions crayfish are important (Table 2). The hawk perches up on large trees or a fence line near somewhat open areas or a wetland waiting and searching for food (Parker 1986). They also can hunt from the ground ambushing prey when they come from burrows (Coward 1985).
Red-shouldered Hawks are highly aggressive raptors, chasing out any other species and conspecifics that are a threat and too close to their nests (Morrison et al. 2006). They have been found to chase out and physically attack other hawks as well as great horned owls, increasing during incubation times (Crocoll 2008). Red-shouldered hawks have found to also be aggressive towards humans in California and Ohio populations (Crocoll 2008).
The red-shouldered hawk prefers extensive mature, upland mixed deciduous forest-coniferous forests, riparian areas, and flooded deciduous swamps (Cooper et al. 1999). Wetland areas are important for this species in prey availability and nesting areas (Crocoll 2008). Red-shouldered hawks also use large mature trees that tend to have a three pronged ‘Y’ shaped growing pattern; a crouch for them to create a nest stand in (Cooper et al. 1999). The type of tree is not as important as the size and shape of the tree. Red-shouldered hawks utilize older trees with larger trunk diameter, usually 12-48cm (Titus and Mosher 1987). They utilize multiple types of trees such as beech, aspen, birch, ash, and oak. Red-shouldered hawks also prefer at least if not more than 70% canopy closure.
There are two main populations of red-shouldered hawks. One population is located in California and has recently spread to Arizona and Oregon. This population is largely non-migratory, only avoiding high elevations during winter times (Crocoll 2008). The other population is an eastern population that spreads from southern Canada to the eastern part of the Great Plains region, to Florida and then all the way up to New York (Figure 5). This population usually wanders west when winter sets in (Crocoll 2008). The populations in California and one in Ohio are beginning to adapt to suburbs and are less particular to their habitat restrictions (Dysktra et al. 2000). Home ranges for red-shouldered hawks vary from 90- 200ha (Crocoll 2008). However during breeding season the ranges decrease and males usually have greater home ranges than females (Crocoll 2008).
Red-shouldered hawks population status in the North American population are about 183,000 individuals, assuming the majority of breeding birds being in the eastern population (Rich et al. 2004). This however is excluding the birds in California. The IUCN (International Union for Conservation of Nature) find the red-shouldered hawk as a species of least concern. According to the CWS and USFWS 2008 the red-shouldered hawk is not listed as any special concern, however, Mexico, Minnesota, New York and Indiana consider them a special concern (Crocoll 2008). In Iowa they are endangered. In Michigan, Wisconsin, and New Jersey they are found to be threatened (Crocoll 2008). In Michigan the main counties where red-shouldered hawks have been found from 2004 to 2006 are: Cheboygan with 50, Manistee with 29, Wexford with 20, Otsego with 19, and a few in Mackinac with 18 (MNFI)(Figure 6). Because of large transects of habitat loss by logging and deforestation techniques for agriculture the red-shouldered hawk’s populations have been declining in the eastern populations (Peterson and Crocoll 1992). In the western populations, as in California and Mexico, populations are decreasing due to decreasing habitat loss for human populations to increase (Crocoll 2008). However the populations in California are beginning to expand more eastward and north, as well are seen to be stable (Wheeler 2003b). The most drastic declines are seen in Michigan, Wisconsin, Illinois and Iowa; a decline of 90% from their pre-settlement population numbers (Crocoll 2008). This is most likely due to habitat fragmentation and therefore habitat loss (Cagnolo and Valladares 2009). In Neithercut woodlands, Clare Michigan, the amount of land is large enough for only one pair of breeding red-shouldered hawks.
Management Goals & Objectives: Northern Goshawk
Goshawk management in North America continues to be contentious (Andersen et al. 2005), partially due to fuzzy nature of the study results. Observational studies with weak inference, and narrowly focused studies not incorporating multiple yet important environmental variables, potentially affect the overall goshawk reproduction models (Moser and Garton 2009). Most of these studies of goshawks have been observational, thus their results cannot provide a solid inference. On the other hand, there is a need for incorporating and the testing of the experimental designs that noted a small relationship between the short-term effects of habitat loss on goshawk breeding area occupancy and nesting success for better understanding breeding success on a much larger scale (Moser and Garton 2009).
Since 1990, there have been a plethora of studies showing a positive correlation between overall goshawk reproduction success and the quantity of suitable nesting habitat at various scales (see review by Anderson et al. 2005). A number goshawk studies that occurred within the European region, suggested a high relationship between the amount of mature vegetation found within a large area and the overall reproductive success of goshawks (Widen 1997). From a number of different studies done on the topic of habitat selection of goshawks (Andersen et. al. 2005, McClaren et. al. 2002, Marquiss and Newton 1982) suggest that, other than variables such as prey availability and weather of a given area, goshawks prefer to nest in a more closed canopy forest. The presence of this closed canopy becomes contiguous with larger stands of trees the more likely the inhabitance of the northern goshawk will be. Furthermore we wish to implement a management strategy for Neithercut Woodland based on primary literature and pertinent publications.
The goals and objectives for managing Neithercut and the surrounding counties and within the state would be to implement the overall regeneration of old growth forest. With this management strategy we would like the forest to: 1) resemble a community in which there is moderate to high canopy closure 2) the preservation of larger trees for nesting purposes, and 3) to maintain any contiguous standing hardwood/conifer stands left in the surrounding areas (Michigan Natural Features Inventory 2007). This being said, the contiguous forests that are located within the more northern portions of the Lower Peninsula and Upper Peninsula and must be managed the same, trying to preserve the contiguity of the forests inhabited or potential for inhabitance by the northern goshawk. As for managing the forests around the area of known goshawk nests, Reynolds et al. (1992) and state agencies within Colorado recommended no commercial timber harvest within a 12 ha buffer zone around the goshawk nesting area, and at least 60% of the 170 ha area surrounding the nest needs to meet certain vegetation requirements. The dependence and observation of the cyclic abundance of both ruffed grouse and snowshoe hair would be taken into consideration as an important management goal. The management of scrub brush and lowland conifer swamps and possible food sources for these prey items would be of more importance when managing strictly for goshawks. There is commonly a delayed response of goshawk abundance and prey densities; therefore long-term monitoring of the forest species (i.e. mice, hares, grouse) would be implemented into our management plan (Tornberg et al. 2005).
Making Neithercut Woodland a possible breeding habitat for goshawks would also be incorporated within the management plan. Neithercut being rich in small mammals such as hare, squirrel, and passerine birds may distinguish this habitat from other more disturbed and urban regions surrounding Neithercut Woodlot. Management would be implemented in the form man-made nesting sites within what was determined to be suitable nesting habitat. The building of these nests out of natural materials would be highly recommended.
Management Goals & Objectives: Northern Harrier
Goal: Increase the populations of birds of prey.
Objective 1: Identify birds of prey whose populations are declining in Neithercut, and then reverse the decline and have it stabilized by 2019
Objective 2: Through 2019, maintain and monitor birds of prey whose populations have been stable or increasing since 1990.
Goal: Increase the understanding and appreciation of these birds of prey and their habitat requirements in Michigan.
Identify all priority bird of prey habitats in Michigan and improve habitat quality at 50% of these sites by 2012.
By 2010, improve management practices to enhance bird of prey populations at Neithercut.
By 2010, develop and begin implementing an outreach program that increases the understanding and appreciation of birds of prey and their habitat requirements in Michigan.
Management Goals & Objectives: Sharp-shinned Hawk
To maintain a healthy population in Neithercut Woods, fragmentation of the available habitat should be avoided. The large wooded habitat of Neithercut woods is suitable nesting habitat for the sharp-shinned hawk with lots of available space to build additional nests as the years and nesting seasons pass. Sharp-shinned hawks also need the low grassland areas of Neithercut to maintain a habitat for the songbirds they prey upon. Trimming or mowing would most likely be the cheapest and safest way to maintain the grass habitats for the hawks to hunt in. Maintaining the thick canopy cover is also important for hiding nests as well as for stealth during hunting. Protection of tall trees with thick canopy cover will be very important for maintaining suitable and safe nesting habitats for when the hawks return each nesting season to build a new nest. If songbird populations were to ever drop, bird feeders can be built in grassy areas; which will also serve as predation sites for sharp-shinned hawks.
Management Goals & Objectives: Red-shouldered Hawk
The reason for aiding the red-shouldered hawk is for the reason that in Michigan they are a threatened species. Neithercut is a protected learning tool for Central Michigan University students therefore the hawks would be mainly protected living here and could help bring back populations in Michigan from threatened to stable. Therefore the following objectives are suggested for Neithercut:
Increase nesting habitat in areas around streams and ponds at Neithercut
Limit the amount of human disturbance during the breeding season
Leave CWD in Niethercut to maintain prey populations
Create a buffer-zone of trees around Neithercut to keep out red-tailed hawks
Plant more birch, aspen, beech, and oak in areas of possible nesting
Using large trees already in Neithercut build crotch nests to attract red-shouldered hawks
Description of Area: Neithercut and Surrounding Areas
Neithercut Woodland is located in Clare County within the middle of the Lower Peninsula of Michigan, approximately forty miles northwest between the nearest reference city, Mount Pleasant. The neighboring counties of Clare County include: Isabella County located to the south, Osceola County to the west, Roscommon and Missaukee Counties located to the north, and Gladwin County to the east. The woodlot is accessible by means of a major highway running along the northern portion of the area, and is owned and managed by Central Michigan University (CMU) Refer to (Figure 7). This piece of land acquired by CMU allows students to learn about local biology and immerse themselves within a more recognized habitat and also interact with local species.
Neithercut’s area encompasses a total of 102 hectares with a diverse make-up of natural resources. This area being rich in natural resources can be attributed to the advance and retreat of the Wisconsin glacier, around 12,500 years ago (Kelly and Farrand 1967). The upturn and glacial till accumulated within this area, makes the changes in elevation from 304.8-336.8 meters observed within Neithercut; the more northern and western portions of the area being more hilly compared to the southeastern portion that are more signified as “gently rolling” (Gorton 1978). With the glaciations forming such unique ecosystems, the formation and growth of such features as Elm Creek, which runs approximately 2.4 km from the southwest corner the northeast region of the property allows for the inhabitance of many invert species and acts as a local reference point for many mammalian and amphibian species (Gorton 1978). Many of Elm Creek’s tributaries and runoff spillways allow for the survival of marshes, swamps, and importantly (for hare) Northern white-cedar (Thuja occidentalis) with constant but variable supply of water year round (Gorton 1978). Relating to the deposition of sediment from the glaciation process, the dominant soil type that persists within the Neithercut region are Nestor loam, Lupton muck and Markey muck, and Menominee loam with mixture of Montcalm loamy sand (Gorton 1978, Clare County Planning Commission 2004).
Vegetation found throughout Neithercut Woodland would typify that of most northern regions of Michigan. Gorton (1978) concluded through both interpretations of orthographic photos and through own personal experience that there was at least nineteen representative vegetation types found within Neithercut Woodlot (Figure 8). The dominant vegetation types found within the Neithercut region are comprised of a mixed hardwood forest (mostly aspen) along with, paper birch, beech, maple, and hemlock. Also included within Neithercut which is worth mention is the presence of an even aged sugar maple community in the more northern regions and patchy within the southern regions of the property (Figure 9) along with many more intermittent species occurring throughout Neithercut.
Before the 1820’s Clare County, in which Neithercut Woodlot resides was an undisturbed dense mixture of white pine (Pinus strobus) and deciduous (oak and maple) forest. During 1856 is when lumber barrens started to move into the area and began to acquire county timber for harvest. With this area being well known for its timber harvest, the surrounding communities were first established for logging purposes and revenue. 1870 marked the establishment of railroads within Clare County, and thus timber harvest had a major impact on local tree numbers and composition. Throughout the 70’s and well into the 80’s Clare County timber harvest was designated one of Michigan’s premier lumbering districts, thus increasing railroad production and timber harvest. During the mid to late 1800’s Clare County forests were basically cleared, leaving an open landscape covered with woody debris and leftover stumps. In the 1900’s is when Clare County started shifting towards a new source of income and job production for its community. The inflow of agriculture production in combination with oil extraction for conversion to natural gas was now Clare County’s main source of revenue. During 1929 Clare County was deemed Michigan’s most productive source of natural gas, but yet no effort existed in conservation of natural resources until 1940. This conservation effort included Duck Marsh being the first piece of land set aside for conservation and protection by Clare County (Clare County Planning Commission 2004).
Josia Littlefield, a “conservationist” within Clare County, owned Neithercut during the time. Littlefield’s death transferred the remaining land he owned into the ownership of his descendants. Through the good nature of his family and effort to preserve Littlefield’s dream, between the times of 1959-1968 CMU was given the right and responsibility as an institution to manage this 252-acre parcel in a way that was deemed appropriate (“Neithercut Woodland”).
Since 1968 Clare County has been slowly moving toward the preservation of more woodlots. The southern portions of the county are dominated by agricultural farmland with the occasional patch of forest. Most of the tree communities within the southern most portions of Clare County are located along rivers, streams and preserved wetlands. With the presence of a highly valued species such as Kirtland’s Warbler (Dendroica kirtlandii) and the presence Pere Marquette State Forest in the northern part of Clare County, conservation efforts within the County are on the rise. With Kirtland’s Warbler being an endangered species, most forest management strategies go into the active management of Warbler habitat (i.e. Jackpine forests) within this state forest (Clare County Planning Commission 2004)
The area that falls within Neithercut Woodland has a high species richness and has a large overall biodiversity; incorporating almost all the factors representing the presence of hawks (i.e. tree density, mature stands of forest, preferred prey species, and water) (Figure 10). Neithercut being on the southern most portion of some hawks range within the state of Michigan may have weight on management decisions. Influence on management decisions in terms of, how much effort should be contributed to the encouragement of inhabitance of the hawks themselves since Neithercut would represent an insignificant portion of its core habitat range.
Neithercut being a small-protected area has its positive aspects, allowing for a sanctuary for small mammals, but maybe excluding species that require vast areas for survival. Neithercut Woodlot being as small as it is 102 ha, in reference to the northern goshawk that encompasses approximately 5000 ha for its home range, it may act as an insignificant portion of the land for management consideration. Other limiting factors within the Neithercut region would be available prey resources within the region itself. Through experimental studies, goshawk productivity was strongly correlated with the relationship between prey availability and overall reproductive success, concluding that overall prey resources may possibly be an important limiting factor in goshawk success in an area (Salafsky and Reynolds 2005).
Management Recommendations: Northern Goshawk
Assuming there would be a high source of income to facilitate the management of the goshawk, it would then be managed on a more statewide scale rather than confined within the Neithercut region. The statewide management plan would include the areas of the Upper and Lower Peninsulas outlined within (Figure 11 and 12). This management would include areas with a high proportion of northern hardwoods and lowland conifer swamp. The growth of these areas would be managed for the development of a mature northern hardwoods stands along with the presence of a mature lowland conifer swamp. This would allow for the production of suitable habitat for nesting of the goshawk. Trees would be managed or protected to ensure the overall growth and productivity of the forest. The requirement of the mixed in lowland conifer would ensure that prey such as ruffed grouse and hare have suitable habitat for survival. The areas referred to in (Figure 11 and 12) represent heterogeneity of both of these land covers, allowing for overall movement of goshawks within these areas.
The areas outlined for statewide management fall within the numbers of highest occurrence of goshawks between 1997-2007. Along with just overall preservation of the outlined areas would be prescribed the management of limiting at least to a certain extent the understory cover within the forest. This understory management would open up the forest a bit, all while contributing to the overall ground cover within the forest. The ground cover would act as sanctuaries or possible breeding habitat for both hare and other small mammals that the goshawk may prey upon.
Now assuming of a low source of funding for the management of goshawk, Neithercut would be managed on a more simplistic view. The implementation and construction of nesting sites within Neithercut would be optimal due to low income. The nesting sites would be placed between 40-50 feet high within most advantageous mature trees (Michigan Natural Features Inventory 2007). A total of three nests would be built within Neithercut to give a plethora of different nesting opportunities for the goshawk (Figure 13). These handmade nests would be placed in three distinct vegetation types within Neithercut: 1) mature upland 2) mature lowland and 3) the circular pine stand within the western portion of Neithercut (Figure 13). This implementation of nesting sites would act as an inviting proposal to the inhabitance of goshawks within Neithercut.
Management Recommendations: Northern Harrier
Populations of the northern harrier have declined in the 20th century due to the loss of natural wetlands and changes in farming practices (Tiner 1984). Wetland areas used for nesting need to be preserved. Farmers should be discouraged from cultivating wetlands through tax incentives. The main focal point of an appropriate habitat should be in areas that already exist. An area that is already under conservation protection would be most ideal.
Other areas such as used wet meadows, dry uplands, brushy areas, open areas and slightly closed forest areas can also provide a suitable habitat (Apfelbaum and Seelbach 1983). There should be at least 100 hectares available for the northern harrier. The habitats for harriers are species-specific. In managed wetland areas, water levels should be kept low during nesting seasons, usually no more than 15 cm from April to August. If the water level is too high the nesting grounds can become flooded and reduce the level of prey. Another management option would to have prescribed burns every 2-5 years depending on growth to reduce succession and advancement of woody vegetation. The prescribed burnings will also maintain the habitat needed for small mammal prey (Kaufman et al. 1990).
Human disturbances should be minimized near nests especially during breeding season and the use of chemical pesticides should not be used anywhere near habitats in use by harriers (Hamerstrom 1986). Human disturbances may cause harriers to abandon their nests. Contaminant repercussions have been well documented in North America (Hamerstrom 1969) showing evidence of thinning eggshells, reproductive failure and death (Newton 1979) relating to the usage of organochlorines like DDT (dichlorodiphenyltrichloroethane).
Surveying of the harrier should only be done by trained land managers and through their survey personnel. Surveillance should be from the first week of May through the last week of July, just after sunrise. Observations indicating an active nest (Bibby 1992) may be a food pass from the male to the female during breeding season. Another indicator may be a hunting female during the nesting season since they will stay close to the nest site. Finally, there would be the existence of fledglings in close proximity to the adults.
Management Recommendations: Sharp-shinned Hawk
Like many bird species, populations of the sharp-shinned hawk dramatically declined due to farming practices. New farming techniques such as pesticides were being administered to crops to kill off insects and maximize crop yield. However, a pesticide known as DDT has a dramatic effect on local bird population causing eggshell thinning and reproduction failure (Henny et al. 1973). With the ban of DDT and the use of safer pesticides, sharp-shinned hawk populations began to increase and remain at a vulnerable status today (Terres 1980). Farming still poses a problem due to habitat loss for the sharp-shinned hawk. Removal of forested and grassland habitats cause a loss of nesting and foraging habitat for the hawks. Any habitat that is currently suitable for the sharp-shinned hawk should be preserved and protected.
As for habitat that is currently occupied by a sharp-shinned hawk, protection of large thick canopy trees should be enforced because of their importance as nesting sites for the hawks. The large trees also provide cover for the hawks while they hunt and for camouflage from their predators. Another management option would be to have prescribed fires on the grasslands to reduce the advance of woody vegetation. These burnings will help maintain habitat for the prey of the sharp-shinned hawk (Kaufman et al. 1990).
In the event of a reduction of small bird populations, bird feeders can be placed in open grassland areas to attract birds for the sharp-shinned hawk to prey upon. The bird feeders should be placed on a post high enough where small mammals cannot reach and should also be squirrel proof. These bird feeders will hopefully bring more songbirds into the area; which are the sharp-shinned hawk’s primary food source (Joy et al. 1994). Certain plants could also be planted in Neithercut to lure in songbirds. Such plants could be elderberry bushes and mulberry trees. The berries from these plants consist of a high portion of songbird diets (Bairlein 2002). The large mulberry trees may also provide nesting habitat for the hawks.
Interaction with humans should be minimized but human disturbance does not seem to cause too much interference with the sharp-shinned hawks. However, humans often bring pollutants into a habitat that can cause reproduction failure and eggshell thinning (Henny et al. 1973). Sharp-shinned hawks also seem to adjust well to human habitats for hunting grounds due to the fact that a lot of people have bird feeders in their yard. These bird feeders are beneficial to the hawks because they attract their primary food source but may cause negative interactions with the property owners. Nonviolent actions should be taken if removal of the sharp-shinned hawk is desired by the property owner. Since all hawks and owls are protected by federal and state law, any individual who is experiencing negative interactions with a sharp-shinned hawk should call a licensed professional to help resolve the problem and not try to resolve it themselves.
Management Recommendations: Red-shouldered Hawk
The management goal for red-shouldered hawks is to make Neithercut woodland look attractive to the hawk hopefully find a breeding pair to inhabit the area. One proposed idea is to increase the area of Neithercut woodland. If the area that was offered to Central Michigan University, across the street to the south end of Neithercut, was acquired then that would help make Neithercut suitable for more breeding pairs of hawks. A more realistic management objective is to provide more nesting habitat for the red-shouldered hawks. This will be done by planting trees that the red-shouldered hawk needs; more aspen, birch, beech, and oak, preferably about 5 trees near each water source. If these trees were planted near the few streams and ponds found in Neithercut that would be prime nesting habitat once the trees age. Also in trees that are already found in the area, use wood and actually build crotches in a few trees that would attract red-shouldered hawks. Preferably build two to four of these nests in areas around the small marshes and streams in Neithercut (Figure 13). Choose trees that are bigger than the surrounding trees. Then with three 12 ft 2x4’s and using nails securely attach them to the main trunk of the tree about halfway up the tree but below the canopy. Then use twigs, leaves, sticks, and bark to dress up the artificial nest. Another objective is to leave the cross woody debris that is already in Neithercut to leave areas for the hawk’s prey to inhabit. The debris is also where the hawks find items to create their nests.
The red-tailed hawk is a main competitor for the red-shouldered hawk; both birds cannot occupy the same area. Therefore by leaving a completely uncut buffer zone of trees around Neithercut will discourage red-tailed hawks from nesting there. The area around Neithercut is fragmented, which is the prime habitat for red-tailed hawks. Therefore using the buffer of uncut trees around Neithercut will help keep the red-tailed hawk away from red-shouldered hawk nesting sites.
Red-shouldered hawks are affected by human disturbance such as cars, hikers, and off-road vehicles. Since Neithercut is a learning tool, complete human disturbance can not be diminished, however, limiting the amount during the breeding season (mid-March to June) would benefit the hawk.
Evaluation Techniques & Monitoring Plans: Northern Goshawk
Evaluation techniques statewide, and within Neithercut, would be used to determine if the management was successful. These techniques would simply be the presence or absence of the species. These bird surveys would be done within the breeding period of March 1st through May 30th. On a more statewide scale, transects should be ran through the prescribed management areas, to account for breeding pairs of goshawks. A total of 10 transects would be ran through each designated management area within the state to account for the presence or absence of goshawk nesting sites. Taking into consideration the existing goshawk nesting sites, transects that would be undergone would evaluate new nesting sites or the current use of old nesting sites. If current nesting sites within the prescribed areas were used, and no new nesting sites were established, the steady population of goshawks would result in no change and therefore success would be measured in the preservation of important habitat for the goshawk. But the purpose of protecting the prescribed areas within the state of Michigan would be to increase the overall inhabitance of the goshawk. So for successful management, the measure of success would be the integration of new breeding pairs within the management areas.
Neithercut woodlot is on the verge of being non suitable habitat for goshawks. Making Neithercut a possible refuge for the goshawk would be the overall goal of management. Evaluation techniques would be similar to that of the statewide management areas. Running transects through Neithercut, and also the monitoring of the nests built by the managers would determine the overall success of the management plan. Overall, the goshawks contribution to the overall biodiversity within the Neithercut region is highly unlikely, but success would be measured simply in terms of the presence or absence of the goshawk itself.
Evaluation Techniques & Monitoring Plans: Northern Harrier
Surveying of the harrier should only be done by trained land managers and through their survey personnel. Surveillance should be from the first week of May through the last week of July, just after sunrise. Observations indicating an active nest (Bibby 1992) may be a food pass from the male to the female during breeding season. Another indicator may be a hunting female during the nesting season since they will stay close to the nest site. Finally, there would be the existence of fledglings in close proximity to the adults. Once a nest has been established monitoring should be done from afar, so the nest will not be disturbed. After the nesting season surveying of the habitat itself can be done: checking vegetation growth, soil samples, water samples, and garbage pick up if needed.
Evaluation Techniques & Monitoring Plans: Sharp-shinned Hawk
Surveying of the sharp-shinned hawk in Neithercut should be done by trained land managers. Surveying should take place during the day since this is when the hawks are active and feeding during the months of May through July when the hawks are present and nesting. Nests can be spotted high up in a thick canopy tree and will be frequently guarded by the female. Young can be spotted in the nest or on neighboring branches of the nest (Rompre 2003).
Success can be indentified as nesting and sightings in the target area. Since the sharp-shinned hawks return to the same nesting site each year and build a new nest in a new tree each year, success could be identified as sightings of the hawks during nesting seasons and new nests being built each nesting season (Rompre 2003).
Evaluation Techniques & Monitoring Plans: Red-shouldered Hawk
Ways to evaluate the success of red-shoulder hawks in Neithercut is to produce red-shouldered hawk calls and wait for a response. Most red-shouldered hawks either call or respond aggressively to conspecific calls (Dysktra 2001). A monitoring technique done by Mary Anne McLeod in her paper, Red-Shouldered Hawk Broadcast Surveys: Factors Affecting Detection of Responses and Population Trends would best fit monitoring them. During the breeding season and preferably in the morning hours: broadcast six calls, each 20 seconds, each at one minute intervals with a 40 second listening period between each call. After the final call, 4 minutes and 40 seconds are to be spent listening for calls back. If a call is heard, look in that direction and using a compass walk that bearing looking for red-shouldered hawk nests. Record all the responses with the date, time of day, the time elapsed before the call was heard, an estimated distance from you to the bird/nest, species, age, and sex if possible of the bird. Perform this technique once every four weeks during the breeding season. Use volunteers such as Central Michigan Students or CMU’s chapter of the Wildlife Society. Do this technique every year at the breeding season to determine if birds are existent in Neithercut. Capturing the birds would probably not be a good idea since we would like to keep the breeding pair in Neithercut and human disturbance could make them find new nesting areas away from Neithercut. We would like to keep the birds as undisturbed as possible. Success would be having red-shouldered hawks present and nesting in Neithercut woodlands. Failure would be no birds present at Neithercut woodlands.
Issues of scale within our management:
Scale of habitat management is a hard obstacle to overcome. Focusing primarily on Neithercut for hawk species would present the problem within the spatial realm of habitat management. Most hawk species within this management plan require and utilize large areas of land, upwards of 6000 hectares. Neithercut encompassing approximately 100 hectares would suggest that for management of hawk species on a small scale such as Neithercut would have very little contribution on a population of hawks within the state of Michigan. Therefore, increasing spatial scale to a statewide management perspective would have an overall greater impact on hawk species within Michigan, taking into account huge landscape management goals. On the other hand, it would be simpler to evaluate success within a smaller spatial scale than it would be to try to determine success based on a statewide or larger spatial scale. More intricate management strategies (i.e. nesting site construction, prescribed burning, water level management, and mowing) would be able to be addressed on a small-scale management plan whereas; on a more large scale management focuses on the contiguity and structure of the forests being managed either statewide or nationwide.
Time scale or the temporal scale is another aspect of management success that is hard to take into consideration when implementing a management protocol. The maturation of a forest takes quite a bit of time; sometimes hundreds of years for development of suitable habitat for hawks. Within a study period (maybe ranging from 10-20 years) it’s hard to measure success. Fluctuations within the climate, forest community, human population effects, and simply the overall species richness associated with a forest are hard to predict. With the implementation of the management of strategies purposed above, this would act as an almost immediate fix for the inhabitance of hawk species within the proposed area. As time progresses the management may seem to work over a short period (i.e. 10-30 years), but as the forests change and other factors such as climate effect the forest species, this would be the hard part of taking into the temporal aspect of management. The most important part of both temporal and spatial implications is to have and “active management” strategy that allows for the pliability of the management prescribed.
Timeline for management: Northern Goshawk
Build nests and place them within three preferred habitat types.
Run 5-10 transects through Neithercut to determine if goshawk is present in area. Record nests/goshawks present.
Run yearly transects to determine the presence/absence of goshawk within Neithercut region.
Run 10 transects through purposed region to determine the presence or absence of goshawks and goshawk nests within study areas.
Determine overall canopy cover and the approximate ground cover within the purposed areas. Manage accordingly (i.e. for hare and ruffed grouse).
Run 10 transects yearly on purposed management areas to determine if goshawks are utilizing the areas for breeding purposes.
Maintain contiguity of the managed areas for the purposed 20-year period (i.e. northern hardwoods, lowland conifer swamp). Managing for 70-80% ground cover.
Add groundcover when needed by cutting more intermediate, non-mature trees for prey habitat.
Timeline for management: Northern Harrier
Acquire land, north of Neithercut. Suitable habitat since it is open wetlands.
Survey only first week of May through last week of July, after the early sunrise.
During April-August monitor and keep water levels 15 cm or less.
Every 2-5 years after breeding season prescribe burns or mowing, depending on growth of vegetation.
Timeline for management: Sharp-shinned Hawk
Maintain current conditions of Neithercut habitat.
Prescribed burns as needed (2 to 5 years) to maintain the grassland habitats.
Protect and maintain tall thick canopy trees as potential nesting sites for the hawk.
In the event of low songbird populations:
Bird feeders will be monitored every 3 weeks. Refill when necessary.
Young elderberry bushes and mulberry trees will need to be monitored every summer until they reach adulthood.
Survey for hawk and hawk nest sightings during the summer months.
Surveying should occur during the day, which is active time for songbirds, which the hawk preys upon.
Timeline for management: Red-Shouldered Hawk
Run transects through Neithercut using a game caller to monitor if any populations of Red-Shouldered Hawks are present.
In August and September build artificial nests at Neithercut; 3 artificial nests in three different locations near water sources.
In August and September plant one of each: Aspen, Paper Birch, Beech, and Burr Oak at five different locations of preferred nesting habitat; near water sources. Plants the remaining trees along the outer edges of Neithercut in areas where the buffer zone is depleted in trees.
Monitor for Red-shouldered hawks in Neithercut by going in the early morning during March, April, May, and June and using a recorded call of a Red-shouldered hawk to try and get a response.
Run monitoring transects every year, one during each month of the breeding season: February thru to July.
Monitor the planted trees growing success.
Prescribed Burning per year: $ 608.79
3 Nests for Red-Shouldered Hawk: $15
Sheppard hooks: $ 27.80
4 Bird feeders: $ 28
Suet Cakes: $ 192
Trees to plant:
Aspen (10): $ 123.60
Beech (10): $123.60
Paper Birch (10): $ 82.40
Burr Oak (10): $123.60
Elderberry Trees (10): $ 87.60
Red Mulberry (10): $ 61.80
Yearly financial plan for man hours: $ 5000
Annual total budget: $ 6474.19
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