It is important to monitor wildlife populations to ascertain how a species is surviving and how that may impact other wildlife populations and forest biodiversity. In many of our state parks, especially in the Hudson Valley, we monitor the deer population and the effect that deer are having on the forest vegetation. One method we use to monitor the deer population is a “distance survey” conducted at night, using spotlights, a range finder (to determine the distance between the deer and the vehicle) and a protractor, for measuring the angle at which the deer were observed. Four people and a vehicle are needed in this survey. Two “spotlighters” sit in the back seat and search for deer, the driver keeps the vehicle at five mph and stops when a deer is seen to get the information on the deer, and a scribe sits in the passenger seat to record the data. Data recorded includes deer group size, sex, age, habitat type, distance in yards and angle from the vehicle. To determine a deer’s sex, the surveyor notes if the deer has antlers or not – age and sex are defined as fawn, doe or buck.
As an example, the above diagram shows a group of two deer at a distance of 3 yards and an angle of 75˚ from the side of the vehicle. The yellow color represents where the surveyors are shining their lights. The surveyor defines this as a group of a buck, due to the antlers, and a doe. These observed deer are in a mowed hayfield, so this habitat type would be recorded as agriculture.
Parks staff Erin Lennon uses a laser rangefinder to find the distance, in yards, that the deer below is from the vehicle, while someone else holds the spotlight on the deer. Note the protractor mounted on the window to determine the angle.
From left to right are the spotlight, rangefinder and protractor used in the survey.
This rattlesnake was about 3ft long and slowly slithered across the woods road in front of our vehicle.
The copper head was slightly more difficult to see, as it blends in very well with the fallen leaves and was staying perfectly still. Only its eye shine in the headlights gave it away.
Click on an image above to read the caption.
After driving the predetermined distance sampling routes, we headed home for the evening. Back in the office, the data obtained will be entered into a statistical program that will calculate the number of deer per square mile in this particular park. This data will be compared to previous year’s data to track the deer population and will help determine future wildlife management decisions.
As the northeast transitions from fall to winter, watch for changes in Parks lakes and ponds nearest you. You might notice that the water churns more than it did during the summer, or you might even notice ice beginning to form at the surface. Such phenomena can mean exciting happenings deeper in the water. One of the most fascinating changes to observe is lake-turnover, or the mixing of cool and warm waters.
Lakes that turn over twice a year are known as “dimictic”: di=twice, mictic= mixing. They are one of the most common types of lakes on Earth. Dimictic lakes freeze in the winter and melt completely by summer. These lakes mix during the spring and fall, after ice melts and before ice forms. Examples of dimictic lakes are seen across New York State, including Shaver Pond in Grafton Lakes State Park, Moreau Lake of Moreau Lake State Park, Lake George of the Adirondack region, and Lake Erie.
Long Pond at Grafton Lakes State Park during spring turnover: ice melting after winter (top), followed by water mixing into the lake (bottom). Fall turnover is the opposite: water mixing followed by ice forming in early winter. Ice photo by OPRHP. Mixing photo cropped from original by L. Schelling, OPRHP.
Without turnover, aquatic life in different areas of a lake may not have enough oxygen or nutrients to thrive. Calm waters tend to separate into layers – with denser, “heavier” waters sinking below less dense surface waters, creating an invisible boundary through which oxygen and nutrients cannot pass. Water is most dense 4 degrees Celsius above freezing (4 OC, or 39OF) and becomes less dense as it cools or warms from this point. In the summer, this means warmer water is at the surface, closer to the air and thus richer in oxygen for fish. Meanwhile a layer of cooler, 4oC water settles at the bottom – where many nutrients accumulate, but also where decomposition of dead animals and plants can lead to little to no oxygen in the water.
Dimictic lake temperature throughout the seasons, with the layering (“stratification”) and mixing of warmer (red) and cooler (blue) waters. Spring turnover results from ice melting, and fall turnover results from wind chilling and mixing surface waters. Image adapted from Figure 44.10 in “Ecology and the Biosphere” (Candela Learning).
As chilly, windy fall weather kicks in, some of the oxygen-rich surface water can cool, sink into the lower levels of the lake, and push the deeper, nutrient-rich waters up closer to the surface. The result is a well-mixed habitat for fish. In dimictic lakes, this turnover happens again in the spring, when the surface ice melts to that heavier, 4oC water and mixes into the deeper waters.
Why are some lakes dimictic and others not? One reason is lake location — dimictic lakes are more common in temperate regions with warm summers and cold winters, where lakes may freeze over completely. Another factor is lake size. Two lakes that are famous for not having complete mixing are Round Pond and Green Lake in Green Lakes State Park. These are the rare “meromictic” (mero=part) lakes which mix in the upper waters but are too deep to allow surface and bottom waters to mix. Alternatively, some lakes may be so shallow that they mix frequently (“polymictic”). NY Natural Heritage Program describes 7 different types of lakes in the state.
Seasonal turnover is important for lake recreation as well as for fish and plant life within lakes. Fishing can improve near the end of mixing periods in lakes that experience turnover, since now oxygen and nutrients will be better distributed throughout the water. Many fish and aquatic life are sensitive to changes in their habitat – oxygen and nutrient levels, as well as temperature changes. Keeping an eye on the changes in the water is useful to biologists and park enjoyers alike.
Post by Erin Lennon, State Parks Water Quality Unit.
The days start getting shorter, the nights are cooler, and the leaves start to turn vibrant colors. Fall is a time of change and when plants and animals start to prepare for the long winter months ahead. It is a great time to get outdoors and observe nature’s seasonal changes.
Broad Winged Hawk. Photo by April Thibaudeau, Thacher Park.
One of the Northeast’s finest wildlife spectacles happens in fall, the autumn migration of hawks. Beginning in early September until the end of November, broad-winged hawks, falcons, eagles, kestrels, harriers, and more travel from their northern breeding grounds south due to scarcity of food during the winter. The birds soar on thermal updrafts, minimizing energy expenditure. A group of birds in a thermal is termed a “kettle” and may resemble a spiral of ascending birds. The migrators utilize these updrafts to glide over ridges and down the coast to regions as far as Central and South America where food is plentiful. Thacher Park hosts an annual Hawk Migration Watch at the escarpment overlook where visitors can help count passing birds and learn more about the species they see.
Burr Oak nut showing the cupule of the acorn, which protects the fruit while it grows and matures. Photo by Ben VanderWeide, Oakland
Plants start dispersing their seeds in the fall by way of wind, water, animals, and even explosion or ballistic seed dispersal. It all starts at the end of August when blackberries, mulberries, and other fleshy fruits start to ripen and fall to the ground. These fruits contain small hard seeds and are dispersed after passing through the digestive system of animals, but make a yummy treat for us! Acorns are theseeds of oak trees and sprout rapidly after falling to the ground. Squirrels can be seen scurrying around this time of year, storing nuts to eat later in the winter. Luckily for trees, squirrels only find about 30% of the nuts they hide – allowing more seedlings to sprout in the spring.
Puff ball mushroom. Photo by April Thibaudeau, Thacher Park.
A warm summer leading to damp September days is the perfect combination for mushrooms to sprout throughout the forest floor. Fungi are made up of a vast underground network called mycelia, which helps decompose leaf litter, dead animals, and rotting wood. The mushrooms we see above- ground are the fruiting bodies of the mycelium and are composed of spores that disperse in the fall to continue the growth of their kingdom. Puff balls, hen of the woods, oyster mushrooms, and fly agaric are just a few of the mushrooms to look for on a forest hike. It is important to have a great deal of knowledge on mushrooms before picking any to eat, as some can be fatally poisonous.
For fall hikes happening at Thacher State Park check out our Program Calendar.
Post by April Thibaudeau, Student Conservation Association Intern, Thacher State Park
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Ooo Halloween is just around the corner. Soon you may be venturing outdoors at night for trick-or-treating or a cool evening stroll. While you are outdoors you just might hear an eerie squawk, squeak, or snort coming from the woods. What is making that sound? In the darkness it is impossible to see, but if you pause for a moment and listen, you might be able to figure out what animal made the sound.
Some familiar autumn night sounds include:
Field Cricket, By Cody Hough (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)%5D, via Wikimedia CommonsThe male Field Cricket song is a series of short chirps, 2-3 per second. Each chirp consists of 3-5 pulses, which are made when he closes his forewing (front wing). Male crickets call from burrows or cracks in the soil. If Halloween is a warm evening, crickets may be calling in fields and other grasslands. Listen to field crickets.
Spring Peeper, Lilly Schelling, NYS OPRHP
Male Spring Peeper frogs normally sing their sleigh bell like mating call in spring, but a few will also sing in the fall in woodlands near small ponds or wetlands. Listen to spring peepers.
More unfamiliar sounds include:
Eastern Screech Owl, By Greg Hume (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)%5D, via Wikimedia CommonsScreech Owls are little owls (about 8” long) that pack a loud call! In 1845 Henry David Thoreau described the call of the screech owl as “A most solemn graveyard ditty, the mutual consolation of suicide lovers remembering the pangs and delights of the supernal love in the infernal groves, …… Oh-o-o-o, had I never been bor-r-r-n.”
Our only small owl with ear tufts, both males and females screech owls sing. A common sound is “an even-pitched trill, often called a “bounce song” or tremolo; and a shrill, descending whinny.” (All About Birds, Screech Owl). Occasionally mated pairs will sing to each other. Listen to a screech owl.
White-Tailed Deer, Lilly Schelling, NYS OPRHP
The otherwise mute White-Tailed Deer will snort when startled. Listen to a white-tailed deer snort. This is one of the few sounds that deer make. Bucks use a series of wheeze-grunt-snort to assert dominance during the breeding season and does and fawns communicate through bleats and grunts.
Raccoon, By D. Gordon E. Robertson (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)%5D, via Wikimedia CommonsRaccoons, those masked, ring-tailed animals, produce a Variety of vocalizations including screams, growls, and whistles. One sound is similar to a screech owl’s call. Listen to a raccoon.
Red Fox Kit, NYS OPRHP
Adult Red Foxes make 12 different sounds; kits, baby foxes, make eight different sounds. These sounds span five octaves and are divided into contact calls and greeting calls. Contact calls, sounds made when foxes are at a distance from one another; start off as a “wow wow wow.” As the foxes get closer, the call changes to a three-syllable call that sounds similar to clucking chickens.
A submissive fox will produce a shriek or high-pitched whine when it greets a dominant fox. And during breeding season males and females may emit a rejection call – a rattling throaty sound termed “gekkering.” Listen to a red fox.
Lower pond site at Point au Roche Park where all 4 turtle hoop traps are set. (Danielle Garneau)
Point Au Roche State Park is a beautiful and diverse park with a lot to offer visitors. By visitors we’re talking both the reptile and human kinds. Not only does the park offer spectacular views of Lake Champlain for park visitors, it also provides great habitat for painted turtles!
Beginning in September 2012, two SUNY Plattsburgh students and Professor Danielle Garneau began their first field experience handling painted turtles. The goal of the project was to compare sex ratio and age structure of turtle populations in both urban, as well as rural ponds in Clinton County, New York. This research is part of the Ecological Research as Education Network’s (EREN) on-going TurtlePop project that is a collaboration among numerous colleges across the country.
Connor Ramsdell and Emily Hastings with their painted turtles in the foreground, as Gillian Dreier-Lawrence, Point Au Roche Park naturalist (background), collapses trap until next session. (Danielle Garneau)
Colleen McAdams measuring carapace (top of turtle shell) length to aid in turtle age determination. (Danielle Garneau)
Participants perform the same experimental protocol to determine if a greater number of adult males exist within urban turtle populations, and if this is a nationwide trend. The decline in young females is thought to result from their high rate of road kill when laying eggs at roadsides. An additional cause of death for urban painted turtles is an increase in the abundance of mesopredators (e.g., skunks, raccoons, opossum, foxes) who raid nests for eggs. Since starting, the TurtlePop project has offered field research experiences to many SUNY Plattsburgh students.
Painted turtle basking on a log with VHF transmitter glued to carapace (top of shell) at the golf course site (urban). Transmitters are used to track animal locations and note movement behavior, nest site selection, and overwintering spots. Note the shedding of scutes (keratin layers) on the top of the turtle shell, which occurs in the middle of summer as turtles grow. Days later this transmitter device fell off the turtle and was relocated along the pond shore. (Danielle Garneau)
About a year into the project, as participants grew ever more curious, a radio-telemetry dimension was added by placing a VHF transmitter on the top of turtle’s shells in order to monitor their movement around a gold course pond complex (urban site) in the city of Plattsburgh. Findings suggest that city turtles do not tend to wander far from the shores of their pond and commonly used basking sites (e.g., downed trees, rocks).
Painted turtles have beautiful shell markings and also have growth annuli (rings) on their plastron (turtle shell bottom) that look like square ridges (visible mid-portion of plastron at top). (Danielle Garneau)
Emily Hastings and Brittany Cole measuring plastron (bottom of turtle shell) length with a caliper to help in determining turtle age. (Danielle Garneau)
Josh Cummings and Gillian Dreier-Lawrence (Point Au Roche Park naturalist) determining what unique marking this painted turtle should have for mark-recapture estimates. (Danielle Garneau)
Ryan Ackerman measuring pre-cloacal (distance from cloaca (place where turtles mate/release waste) to edge of shell) tail length, a measurement used to determine gender in turtles. (Danielle Garneau)
In the summer of 2015, with the help of Point Au Roche State Park Naturalist and SUNY Plattsburgh Ecology alumnus Gillian Dreier-Lawrence, park visitors and college students had the opportunity to participate in and contribute to this growing collaborative research effort at Point Au Roche State Park. We are learning that Point Au Roche State Park has high turtle abundance; approximately 33 individuals were caught over three months of trapping in the lower ponds. Plans to further investigate the turtle population at Point Au Roche are in the works, as the large number of turtles found indicate that the population size at the park is likely quite large, only 11 marked turtles have been recaptured so far!
Post by Danielle Garneau, Associate Professor at SUNY Plattsburgh
![Field Cricket, By Cody Hough (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons](https://nystateparks.blog/wp-content/uploads/2015/10/cricket1.jpg)
![Eastern Screech Owl, By Greg Hume (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons](https://nystateparks.blog/wp-content/uploads/2015/10/screech.jpg)
![Raccoon, By D. Gordon E. Robertson (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons](https://nystateparks.blog/wp-content/uploads/2015/10/coon.jpg)
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