Ecosystem
The landscape of Mackinac Island comprises fields, meadows,
marshes, swamps, bogs, coastline, boreal forest, limestone formations
and caves. Mackinac Island lies in the Alleghenian Zone, a transitional
habitat zone between the Carolinian zone to the south and the
Canadian zone to the north. The Hemlock-White Pine hardwood
forest has a rich undergrowth of birch, elm and maple. On the
Island,
Mackinac State Historic Parks preserves the environment
for all plant and animal life while at the same time provides
an atmosphere for humans to reflect, explore and rejuvenate
their spirits. Taking the time to explore the landscape while
respecting the environment is an integral part of the Mackinac
Island experience.
Natural Features
Mackinac Island State Park provides opportunities for visitors
to experience firsthand the unique features of a northern boreal
forest and witness the effects of receding glaciers. Natural
landmarks such as the slowly-eroding limestone formations of
Arch Rock, Devil’s Kitchen and Sugar Loaf encourage visitors
to adopt a system of measuring time in hundreds of years, rather
than in the hours, minutes and seconds of everyday life in the
twenty-first century.
The physical structure that has become Mackinac Island today
began to emerge over 15,000 years ago as the great glaciers
receded. The Island rose above lake-level and the erosive action
of the ancient Great Lakes against the Island’s limestone bedrock
created today’s cliffs and rock formations. Salt deposits under
the limestone were washed away, leaving cavern holes in the
rock. Weakened by the removal of the softer minerals within
its many layers of limestone sediment, much of the rock shattered
and collapsed. As the water levels fell, dissolved minerals
became concentrated and bound the limestone fragments together
much like cement. The resulting rock is known as breccia. The
brecciated limestone is seen throughout the Island and its fragile
form is noticeable, as lime-loving cedar roots have penetrated
cracks, forcing rocks apart, creating rockslides along the bluffs.
Since the limestone is obviously fragile and breaks easily,
no climbing is allowed on any limestone formation. The Mackinac
Island State Park has erected barriers to protect the 15,000
year-old formations from destruction accelerated by human contact.
At this point in Mackinac’s geological history, the island is
2200 acres in size: two miles wide, three miles long and eight
miles around. All natural formations listed below can be visited
without charge and are within boundaries of the
Mackinac Island
State Park. The Mackinac Island State Park has posted signs
directing visitors through the many riding, bicycling and walking
trails to all natural features. All can be reached by bicycle
and some are within easy walking distance of the downtown area.
Arch Rock
Rising nearly 150 feet above the water, Anishinaabe-Ojibwe tradition describes Arch Rock as the place where the Great
Creator blew the breath of life into the newly created earth.
According to legend, Arch Rock is also the gateway through
which the Great Creator passed on his way to Sugar Loaf, his
Island home. This limestone formation can be seen from M-185,
high above the Island’s exterior lakeshore on the Island’s
east side. To get a closer look, a wooden stairway and nature
path leads from the lakeshore road up the bluff to the uppermost
part of the formation. Arch Rock is also accessible from many
trails in the Island’s interior. For those who prefer to see
this natural wonder in a more leisurely fashion, the limestone
monument is one of many featured stops on the Mackinac Island
Carriage Tour.
Devil’s Kitchen
This excellent example of a limestone cavern created by the
effects of erosion and cedar-root displacement of rocks can
be seen from ferryboats approaching the Island west of Grand
Hotel. An easy bicycle ride along M-185, Devil’s Kitchen is
a popular picnic spot and resting point where travelers enjoy
the view of the Mackinac Bridge and the many freighters passing
through the Straits.
Sugar Loaf
The dwelling place of the legendary Great Spirit or Gitchie Manitou until the coming of the Europeans, this limestone bluff may
be viewed from the ground up from the road below or by looking
down from Point Lookout. A long wooden stairway nearby leads
travelers up the bluff to Point Lookout. Sugar Loaf, once
surrounded by the ancient Lake Algonquin, is a cone-shaped,
brecciated limestone formation rising 75 feet above the forest
floor. Sugar Loaf can be reached by foot trails or by bicycle
and is a popular Nordic skiing destination in the winter.
Skull Cave
Below Fort Holmes on Garrison Road, Skull Cave is believed
to have been the hiding place for English Fur Trader Alexander
Henry during Pontiac’s Rebellion in 1763. His close friend,
Ojibwe chief Minavavana sent him to hide in the cave on a
bed of human bones in order to save him from death.
Mammals
The Straits of Mackinac have served as a barrier for all sorts
of land mammals, although occasionally, larger mammals like coyote, wolf, deer or bear may make the three to seven mile journey
over to the Island by crossing the ice bridge in the winter.
The most abundant species of mammal living on the Island is
the bat, the only mammal capable of flight and therefore the
only mammal for which the straits pose no significant barrier.
Having found a comfortable ecological niche on the Island,
Mackinac’s bats eat insects and nectar from flowers, pollinate
plants, disperse seeds and control insect populations. One
bat is capable of eating up to 600 mosquitoes an hour and
each bat usually eats for several hours every night. As the
sun sets on a mid-summer night, this Mackinac Island favorite
can be seen eating mosquitoes and other insects, serving as
a natural form of pest control. With the limestone caves abundant
throughout the island and the large supply of insects and
plant life, Mackinac’s ecosystem is ideal for the bat and
the bat is ideal for this ecosystem.
Wildflowers
Mackinac Island has long been admired for its natural beauty.
Because of the topography, geological history, soils and climate,
there are a great variety of niches supporting over six hundred
species of vascular plants.
Spring finds the forest floor covered in a mixture of spring
ephemerals including Large Flowered Trillium, Trout Lily, Spring Beauty, Hepatica, Violets and Yellow Lady Slippers.
By summer, these give way to the Wood Lilies, Buttercups and
Hawkweeds. The wetlands along the shoreline are blessed with
a variety of orchids, Fringed Gentian and Jack-in-the-Pulpit.
Six species of asters including Tall, Zigzag and Ohio cover
the fall landscape under the dramatic show of colors given
by the Maple, Birch and Elm trees of Mackinac’s boreal forest.
Snow blankets the Island during the winter months when the
dark greens of the Cedar, Pine and Spruce contrast with the
red berries of the High Bush Cranberry and the mahogany stems
of the Red Osier Dogwood.
The diversity of the plant life, rich contrast and splashes
of color create a stunning backdrop for Mackinac’s wildflowers.
Yet, it is the quiet announcement of seasonal change through
the wildflowers that makes one appreciate the natural beauty
of Mackinac Island’s living landscape.
Enjoy Mackinac’s abundance of natural beauty, but remember
that state law prohibits the picking of wildflowers.
Birds
A popular migration spot, Mackinac Island is a resort habitat
to many species of birds. Because birds dislike flying over
cold waterways, they often "island-hop" across the
Great Lakes to their summer homes in the north. Golden and Bald Eagles, Sharp Skinned, Red Tailed and Broad-Winged Hawks are especially abundant in late April and early May while
the Yellow Warblers and American Redstart and the iridescent
blue color flash of the Indigo Bunting flying past pleasantly
startles and excites visitors during the early summer months.
Many birds prefer to roost or rest by Mackinac’s shoreline;
these include Herrings, Ring Billed Gulls, Cormorants, Red-Breasted
Mergansers, Great Blue Herons, Canadian Geese and Loons. During
the winter months the Snowy Owl and Great Gray Owl fly south
from the arctic to hunt and enjoy the "warmer" climate
found on Mackinac Island.
The musical "ze-ze-zu-ze" call of the Black Throated
Green Warbler can be heard as well as the puzzling and unusual
call of the Veery. The Island’s most aural year-round resident,
the red-crested Large Pileated Woodpecker regularly delivers
its "Woody Woodpecker" call across the landscape.
Other year-round residents include Black Capped Chickadees,
Cardinals and Blue Jays.
