and Natural History
The Mount Holyoke campus encompasses a surprising diversity of
natural habitats including: a stream, two lakes, over a dozen vernal
pools, a forested wetland, shrub covered wetlands, emergent aquatic
plant covered wetlands, upland forests (hardwood, conifer and mixed),
Hemlock stands and open fields.
Due to the great diversity of habitat types, we expect that the
diversity of animal and plant life on campus should be high. However,
little is know about what species are found on campus. As part of
an effort to inventory campus biodiversity, the CE has begun to
survey the vernal pools (important habitat for many species of amphibians
and other wildlife) found on the MHC properties. Biodiversity surveys
are being extended to include other species of animals and plants.
The campus is located in the center of a mostly suburban/urban
mosaic of land uses. The undeveloped part of campus is large enough
to support populations of deer, several species of amphibians and
the Pileated Woodpecker. Because of the size and location of this
habitat, the campus properties can be viewed as an important conservation
area in an otherwise developed landscape. In addition, the diversity
of habitats on the MHC campus provides an opportunity to use the
campus as an outdoor environmental classroom.
In this section of the CE website, we will provide information
on campus habitats, biodiversity, campus nature trails and possibilities
for restoration work on some areas where the habitat is degraded.
Follow the links below for more information on each of these subjects.
There are several types of wetlands found on campus
including: forested swamps, scrub/shrub wetlands, wetlands with
emergent vegetation, and vernal pools. Wetlands are areas of high
productivity and high species diversity. The CE in conjunction with
MHC faculty and students are conducting more detailed surveys of
the wetlands on campus. Check this page for updates on our mapping
Wetlands are areas where the presence of water close to the surface
of the ground determines the characteristics of the soils and the
types of plants and animals found on the site. Wetlands sites are
by definition saturated or covered with water periodically. This
periodic inundation changes the characteristics of soils and tends
to favor hydrophytic (adapted to wet soils) plants.
on Campus [PH]
There are three dams across Stony Brook on the MHC property. Two
of these dams created the two artificial lakes on campus. The other
dam is a spillway in front of the Willits-Hallowell Center.
Dams can be created in several ways. They can be built by people
and beavers, or they can be created by geological processes like
landslides or ice jams. Dams have many effects on the environment
of rivers and streams. These effects on flowing waters can be either
positive or negative depending on the size, location, mitigational
structures present of the dams, and the types of organisms present
in the aquatic environment.
Dams create reservoirs, inappropriately named as lakes and ponds.
These bodies of water provide habitat for wildlife, areas for recreation,
and supply water to human populations and agriculture.
Dams raise the water table of the area upstream. This may create
new wetlands, may change the type of vegetation surrounding the
area, and create problems with local hydrology (how water travels
underground). This can also destroy certain types of upstream wetlands
(i.e. bogs may be flooded and destroyed).
Dams change the flow regime of a river or stream. The area downstream
from reservoir often experiences moderated cycles of high and low
stream flow. Some natural habitats require intense seasonal flooding
to maintain their character. For instance, the Colorado River in
the Grand canyon has experienced a decline in the number and extend
of sandy banks and small islands. A recent experiment (river allowed
to flood at levels that existed before damming) showed that intense
flooding was required to maintain the geological processes needed
to built the sand banks. In addition, some species of wetland plants
require a specific regime of flooding to grow and reproduce.
Dams can impede the migration of fish and other organisms - Many
runs of anadromous fish (live in ocean and breed in rivers or streams)
are blocked by dams. As a consequence populations of Salmon species
and other fish have declined in watersheds are are dammed. Some
of this impact can be mitigated by fish ladders or elevators and
trucking fish up/downstream. These measures are not always effective
in restoring fish populations and the only alternative is to remove
the dam. Dams have been removed from rivers in Maine and are under
consideration along the Sake River in the western US.
Dams slow the flow of water. This may cause siltation of the water
body, increase evaporation , and increase the temperature of the
water. Upper and Lower Lake on the MHC properties are both filling
up due to siltation and will need to be dredged if they are to retain
their current character as open bodies of water.
The 328 acres of property of the Mount Holyoke Trustees contains
278 acres of forests. Hemlock stands on campus provide valuable winter habitat for several
species of wildlife, as well as nesting habitat for owls.
84.8% of our campus is forested. The remaining is fields, lakes,
wetlands, stream, a golf course and the built area.
There are several different types of forest stands on the Mount
Most of the stands are between 60 to 80 years old.
Hemlock Woolly Adelgid [LB]
An exotic insect pest, the woolly adelgid has
completely destroyed stands of eastern hemlock in southern range
of this tree. Detected on the campus, this insect can kill a Hemlock
in as little as 4 - 10 years after initial infection.
The MHC campus has 95 acres of Red Maple forest.
These stands are located along Stony Brook and a large stand is
bordered by Park St., Morgan St., Stony Brook, and the Equestrian
Center. The later area is the site of several vernal pools and
seeps (areas where the groundwater reaches the surface and runs
off in small streamlets and creates patches of soil that are saturated
The mid-story of this area has many small White Pine (Pinus
strobus) between 2 to 30 ft. tall. When these trees mature
they will change the character of these stands, by providing more
evergreen cover and increasing the acidity of the soils.
The ground layer of these forested wetlands is dominated by Cinnamon
Fern (Osmunda cinnamomea) and other hydropyhtic plants.
Forested wetland understory
In places the understory has been invaded by exotic
shrubs including Japanese Honeysuckle (Lonicera japonica)
and Privet (Ligustrum vulgare). These invasive exotics tend
to exclude native vegetation and often have a lower value to native
MHC properties is the 28 acres of the Long Farm Tract.
This area consists of a large 23 acre field and an adjacent 5 acre
field. The Long Farm is currently used as a hay field and jumping
course for the Equestrian Center. The field is fertilized and mowed
two to three times a year. This current management regime has a
negative effect on the biodiversity of the site.
Grasslands are among the rarest habitats in the northeast.
A combination of forest reversion from pasture and modern haying
schedules have reduced the acreage and ecological quality of northeastern
grasslands. Fields that were hayed once in the late summer are now
fertilized and mowed up to three times a season. High inputs of
nutrients decreases plant diversity by favoring a few species that
outcompete others. Butterflies, moths, and other insects that depend
on specific host plants are also lost when plant diversity decreases.
In addition, by mowing during the grassland bird breeding season,
species such as Grasshopper Sparrows, Savannah Sparrow, Bobolinks
and Meadowlarks lose the nest and the foraging area's they need
to raise their young.
Restoring grassland for biodiversity is a relatively easy task
- change the mowing regime to mimic natural disturbances and in
some cases seed the area with native grasses and forbs. Mowing can
be done in the late summer after birds have breed. The CE is currently
drafting a plan for managing the Long Farm as a grassland preserve.
View of small section of Long Farm near barn - this
area is mowed less frequently then the rest of the tract and has
a higher diversity of plant. It is an indication of how the rest
of the area may look if less intensive management practices are
(Lake) Habitat [PH]
The two lakes on campus are Upper and Lower Lake.
Both bodies of water are dammed reservoirs. They are characterized
as shallow lakes with short retention times (water passes from inlet
to outlet in short time). Both lakes are also high in nutrients
- eutrophic to hypertrophic. Nutrient loading occurs via inputs
from Stony Brook and migrant and non-migrant waterfowl (Canada Geese
and Mallard Ducks). In addition, the Golf Course and Equestrian
Center could provide nutrient inputs, however this has not yet been
assessed. Currently the Golf Course withdraws water from Upper Lake
- it has been determined that withdrawals from Stony Brook when
the flowrate is low could result in further eutrophication of the
Habitat - Stony Brook [PH]
The heart of the MHC campus is the Stony Brook watershed.
We have currently begun a program to monitor and assess the ecological
condition of the stream. Based on this effort we will make recommendations
Stony Brook is the largest stream on the MHC property. Several
smaller intermittent streams feed into Stony Brook.
Stony Brook is a warm water stream. On the MHC properties it includes
a relatively undisturbed section that runs through forest and several
sections that are bordered by roads and buildings.
The biological character of this stream is determined both by its
geomorphology (shape, gradient, stream bed characteristics) and by
human influences. These influences include impacts from the surrounding
watershed (agricultural runoff, construction and industrial effluents)
and from within campus (runoff, alteration of the stream channel,and
alteration of the vegetation adjacent to the stream).
Runs, riffles, and pools - the water course of a
stream can be divided into four broad categories of habitat based
- deep moderately fast reaches.
Riffles- high gradient sections with high turbulence.
Pools - calm sections where sediments tend to collect.
Each type of habitat provides homes for different types of stream
Deeper calmer pools may support emergent and floating aquatic vegetation.
Sections of the riparian corridor on either side of the stream have
been severely modified by human activity. A riparian buffer zone provides
cover for wildlife, stabilizes the bank, and can filter runoff before
it reaches the stream. If the buffer is too narrow it cannot effectively
provide these functions.
The Mount Holyoke College properties have at least a dozen vernal
pools. Four of these pools have the definitive characteristics of
vernal pools and also have the organisms found in vernal pools.
If you've seen a small pond in the middle of a forest
or edge of a field that drys-up during the summer, you may be looking
at a vernal pool. Vernal pools are a critical wetland resource for
many species of animals and plants. Animals that require vernal
pools for part of their life, usually breeding, are referred to
as obligate vernal pool species. Obligate species include several
species of salamanders, frogs and the fairy shrimp. These obligate
species require bodies of water that are free from predators and
remain wet for at least two months during the spring. Vernal pools
typically dry-up sometime during the summer or every few summers.
This keeps fish, the predators obligates must avoid, from establishing
Obligate vernal pool species observed on MHC
In addition to the obligate species found in vernal
pools, other species use vernal pools for breeding or feeding, but
can use other habitats as well. Species that are found in vernal
pools, but do not require them are known as facultative species.
Facultative vernal pool species observed
on MHC Campus
Vernal pools can be found in many types of habitats: along stream
or river corridors; in forests; and in open fields. They are defined
by their lack of fish populations and they must contain water for
at least two months of the year.
Breeding Amphibians and Vernal Pools (species marked with
an asterisk in the tables above)
One way of finding a vernal pool is to use your ears. During the
early spring many species of frogs will travel to vernal pools to
breed. Males attract females to the pools and other males with loud
and conspicuous calls. The first frogs to arrive at vernal pools
are Wood Frogs (call like quaking of a duck), which are usually
followed by Spring Peepers (call sounds like a high long trill).
The sound of these choruses can sometimes be heard from a great
distance. When the females arrive at the pools they will pick a
male. The males clasps the female on her back and he releases sperm
while she releases her eggs. Some species release their eggs in
conspicuous egg masses. These masses have a gelatinous appearance
with a central dark spot. Other species lay their eggs in smaller
clusters or singly. The eggs develop into tadpoles and until they
metamorphose into frogs, they spend their time feeding in the vernal
pools. Once tadpoles develop feet and absorb their tails they leave
the ponds for the uplands surrounding the pool. Some years the pond
drys-up before they finish this process and the populations breeding
attempt for that year ends in failure. Small shallow pools are more
likely to dry-up before the frogs emerge than larger deeper pools.
A salamander's use of vernal pools is a less conspicuous and lengthy
affair. During the first warm rain in March salamanders will move
down from the uplands into vernal pools. Their they will perform
courtship displays. When a pair finds each other suitable, the male
will deposit a spermatophore on the pond bottom. The female then
walks over the spermatophore and takes it into her genital opening.
She then uses the sperm contained in the spermatophore to fertilize
her eggs. Depending on which species, she will either lay her eggs
in egg masses attached to sticks or deposit her eggs in small groups
or individually. The eggs hatch and the salamander larvae spend
several weeks feeding and developing into a juvenile salamander.
The young salamanders then leave the pool for the surrounding upland
and Parkland Habitat [PH]
- Habitat fragmentation barrier to animal movement
- Storm Water runoff - oil, gas and road salt runoff from roads
and parking lot in Stony Brook and campus ponds
Middle Connecticut & Stony Brook Watershed[PH]
A watershed is a geographic area in which all surface
and ground waters flow through a common drainage - series of streams,
rivers, ponds and lakes. The Connecticut River drains a watershed
that crosses three state boundaries. Many smaller watersheds or
sub-basins flow into the Connecticut River watershed. For
more information about watersheds, visit the following links and
Map of Middle Connecticut watershed and some of the smaller
rivers and streams that empty into the Connecticut River.
Areas marked in purple do not meet the water quality standards
of the Clean Water Act.
Location of Middle Connecticut Watershed
The Pioneer Valley is in the southern part
of the Middle Connecticut watershed.
The Connecticut River watershed
has been divided into three sections: upper, middle, and lower.
This was done to ease regulation and management of New England's
The Pioneer Valley, which includes
Stony Brook, is within the Middle Connecticut watershed. The Stony
Brook and Bachelor Brook watersheds are the two major drainages
in the area surrounding Mount Holyoke College.
Streams in South Hadley
1) Dry Brook
2) Bachelor Brook
3) Stony Brook
4) Buttery Brook
5) White Brook
6) Connecticut River
Ponds in South Hadley
a) Pearl City
e) Stony Brook
f) Leaping Well Reservoir
g) Upper & Lower
Brook Watershed Land Use[PH]
Mount Holyoke College is located
in the Stony Brook watershed. The
water quality of a watershed is in large part determined by the
types of land uses and their extent within the drainage.
Land use in the Stony Brook watershed is dominated
by human activity (53.7%).
Stony Brook Watershed Land Use 1985
Depending on the land cover, the impacts on water quality may influenced
by different factors.
- Agriculture - fertilizer, manure, manure and soil runoff.
- Human - Stormwater runoff, sewage, lawn chemical, and industrial
- Vegetation - type of vegetation may determine nature of runoff.
Survey of an important group of bioindicators of stream quality.
Fish found on the campus properties (Stony Brook,
Upper lake and Lower Lake): PDF Excel
|Brown Bullhead Catfish
||Ictalurus spp. (several species)
Birds [PH] Excel
Reptiles & Amphibians
The Botanical Gardens has been cataloging the plants
in their greenhouses and campus trees, shrubs and plants on the
landscaped parts of campus. They have developed a database and
posted information about their collections on their Web site.
Non-native Plants [PH]
Several species of invasive shrubs have established
themselves on the MHC properties. These plants tend to displace
native plants and are often less valuable to wildlife.
Privet (Ligustrum vulgare)
is a climbing vine that has paired opposite leaves. The
fruits turn black when ripe and are dispersed by song and
European Honeysuckle (Lonicera
opposite elliptical leaves that are hairy underneath. Fruit
is bright red and dispersed by birds
||Japanese Barberry (Beberis
alternate small leaves. Stems thorny and fruit red. As with
many invasive shrubs, seeds are bird dispersed.
Other invasive species on campus include: Multiflora
Rose (Rosa multiflora) and Burdock (Arctium minus).
- A non-native aquatic plant [PH]
The waterchestnut (Trapa natans) is
an introduced floating aquatic plant that often forms dense
on the surface of lakes and ponds. The mats block light to the
water and can adversely effect other aquatic organisms. These
mats tend to displace native aquatic vegetation that is more
valuable to wildlife. In addition, the presence of waterchestnut
recreational uses of water bodies such as swimming and boating.
Waterchestnut is identified by a rosette of diamond shaped leaves.
Each leaf is serrated on the outer margins and smooth on the inner
margins. The stalk of each leaf has an enlarged region which acts
as an air bladder and keeps the plant afloat. Several rosettes
are attached to a central root that is anchored in the mud.
The plant is able to grow from the main root. Therefore,
the root must be removed to effectively eradicate this weed.
The seed of the plant is black, hard and has four
sharp spines. Seed can float and provide a way for the plant to
disperse to downstream waters
First recognized as a problem on campus in the 1940's,
during the last several decades efforts have been made to eradicate
this weed from Lower Lake. The primary control methodology has
been mechanical raking of the lake using an aquatic weed harvester.
The College has employed Aquatic Control Technologies, Inc. to
annually harvest waterchestnut on Lower Lake. This method is useful
when the waterchestnut population has already exploded. However,
unless the remaining waterchestnut that is left behind is removed
by hand, the plant will quickly reestablish itself. (Photo courtesy
of MHC Archives)
Waterchesnut has recently invaded Upper Lake. Found
in ponds and lakes upstream from Upper Lake, the plant probably
colonized the lake by seeds washed down Stony Brook.
In an effort to prevent Waterchestnut from establishing
itself on Upper Lake and to enhance the eradication efforts on
Lower Lake, students and Staff of the CE spent two afternoons
on the Lakes removing the weed by hand.
The CE will biannually organize student teams to
remove Waterchestnut from the campus lakes. This effort could
help eradicate the weed from campus and potentially save the college
thousands of dollars.
Since waterchestnut may invade campus from upstream,
we will have to remain vigilant to prevent reestablishment.
Page designed, created and maintained by Leszek Bledzki
Peter Houlihan – text and pictures marked [PH]
Leszek A. Bledzki – text and pictures marked [LB]