April 2, 2018

What is this squirrel doing?

By Eric D'Aleo

Gray squirrels are ubiquitous and sometimes downright annoying to homeowners. Raiding birdfeeders, chewing on siding, or getting into an attic, give these tree-loving rodents some bad publicity. Aside from frustrating humans, squirrels are intelligent, curious, resourceful, and have some interesting behaviors. One common behavior is their seasonal hoarding or burying of nuts and seeds. This allows squirrels to survive through winter, since they feed on nuts hidden earlier in the year. Look at the video below and notice this industrious behavior occurs from spring through fall. Bu watch carefully, squirrels may sometimes fake bury a nut to fool other squirrels or birds from locating the food.

Along with storing food to eat at a later time, squirrels are interesting to watch feed. They eat a variety of food items, including nuts, seeds, fruit, mushrooms (fungi), tree buds, an occasional insect, and even bird nestlings. However, the majority of their food is nuts. What two food items can you see the squirrel eating in the video below?

Some behaviors squirrels engage in leave us scratching our heads in wonder. Take a look at the final video and see if you can determine what the gray squirrel is doing.

Squirrels are territorial animals and mark their territories to let other squirrels know an area is “occupied.” This behavior benefits both the intruding animal and the resident squirrel as it sets a boundary and reduces potential conflict. Squirrels mark areas in their territories by urinating on objects or by rubbing scent on logs or other objects from glands located near the mouth. Squirrels may also mark their territory by gnawing vertical strips in a large tree to provide a visual and olfactory cue to other squirrels in the area.

These are only three squirrel behaviors caught by the trail cameras, but many of us see squirrels engaging in other behaviors around bird feeders, scolding predators from a tree, or chasing each other through the branches. Who knew that squirrels led such busy lives?

March 26, 2018

Stories to Tell – Winter Clues

By Eric D'Aleo

Each trip outside to check the trail cameras is an adventure because I don’t know what I will find. Most of the time it is routine with the unexpected being the images captured by the cameras, but that is not always the case. Sometimes scat is left behind and the identification mystery begins. Questions run through my mind as I study the scat on the ground. Is the scat in a prominent location, such as a rock, log, or in the middle of a trail? How large is it and what is its shape? Are there any food items identifiable in the scat? Scat is found throughout the year, but for tracks, winter is the best time of year to look for them. I see many tracks as I move from one camera location to another. Sometimes they are fresh and easy to identify and other times they may be days or weeks old, making identification more challenging. Again, I run through a series of questions to help me identify the tracks. What’s the size of the track? How many toes are visible? How is the animal moving? Is it walking, bounding, or hopping? Where are the tracks located? Are they in a forest, in a field, or in a wetland? Do the tracks lead to a tree, a brush pile, or a burrow? The answers to these questions may provide a clue as to what animal made the tracks.

Look at the scat and tracks that were found during the past year and see what ones you can identify.

Occasionally, other unusual signs of an animal’s presence are discovered. Look at the photo below. What do you think was found on the snow this January? At the time of discovery, the snow had a hard crust and there were no foot-prints in the area. The location was near a trail camera, but was not in its line of view. When I checked the camera’s memory card I saw no evidence an animal had been in the area since the last time I had been there. The area is a mixture of conifers, mostly hemlock, and hardwood trees, beech, red maple, and oak. The object was not found near any tree. So, what was it?

The tail of a flying squirrel! My next question of course was what happened to the rest of the animal? This question was left unanswered since the hard snow crust offered no additional clues.

A similar experience happened in early March. Again, the body part from an animal was found on a hard snow crust with no animal tracks nearby. However, it was found in the snowbanks of a parking lot. Look at the photo below to identify what animal it came from.

It was the foreleg of a white-tailed deer. How had it died? Did it starve? Was it preyed upon? What animal brought the leg and left it here? Was it left there on purpose, was the amount of meat left on the leg too small to hold on to, or was the leg dropped to flee quickly from the area? More unanswered questions, but ones that keep me coming back for more, like a good mystery. What animal stories are waiting to be discovered where you live? Find out.

February 26, 2018

Stories to Tell - What Time is it Mr. Fox?

By Eric D'Aleo

The children at Blue Heron School play a game called What Time is it Mr. Fox? A child who is the Fox calls out a time (1 o'clock - 12 o'clock). The other children take that many steps toward the fox. When the group gets close to the fox, but not past him, and asks, “What time is it?” the fox yells, "Midnight," and turns and chases the group around to tag someone. The children enjoy the game and play it often.

Watching the children play got me wondering if our trail cameras could tell us anything about red fox activity throughout a year. It turns out, they can.

By looking at the information collected from each camera from January through December, red fox were photographed or videoed over 1,600 times. We plotted the number of sightings with the time each image was captured and graphed it. The results are in the charts below.

Red fox are most active early in the morning from midnight until five o’clock in the morning and in the evening from five o’clock till midnight. The highest activity occurs at three o’clock in the morning and six o’clock in the evening. Even though activity levels drop dramatically during daylight hours, and remains low, it’s still about sixteen percent of peak activity level. So unlike in the game where midnight is the time when Mr. Fox comes out to hunt, seven o’clock at night is more accurate. The data collected here at the Science Center corroborates research defining red fox as crepuscular, active at dawn and dusk, or nocturnal, active at night. But what about monthly activity during the year, are there some months with higher activity than others?

It appears there is one time of year when the sightings peak, which is early spring. This is when red fox raise

their young. One camera was positioned near a fox den. We saw the first sightings of the pups outside the den, early in April at night. When they were young, the pups required parental supervision. An adult red fox watched over them while they ran around, played together, and investigated their surroundings. As I reviewed video footage I was reminded of a human parent watching their children play at a playground. The camera also recorded evidence of the parents bringing food to their offspring and scenes of pups fighting over feathers and woodchuck fur. As the year progressed into summer the young foxes were still around and sighted by the camera, but less often. They may have been learning how to hunt from their parents or accompanying them as they patrolled their territory. There was no need for them to return to the den on a regular basis. By autumn the sightings declined suggesting the breakup of the family and the dispersal of the pups in search of their own territories.

What I find interesting is that this information leads to asking other questions about red fox on Science Center property. Do they have a preference for a particular natural community (field or forest)? Do they use a community more at one time of the year than at another time? What other species in the area are active at the same time of day? Are they most active at the same time of the year? Do they have the same habitat preferences? Answers to these questions may be found on line or in a library, but carrying out these observations on our property gives us a better understanding of what is happening locally. It helps us better appreciate of the land and provides an understanding of the requirements and habits of the animals living here. This information can be helpful to landowners considering how changes to a piece of property will affect local wildlife. What time is it for the animals where you live?

February 12, 2018

Stories to Tell - Bear curiosity or Bear destruction?

By Eric D'Aleo

It was the day before Halloween and the sky was gray and overcast. The area had just received a heavy storm that deposited over five inches of rain in twenty-four hours. Strong wind accompanied the rain and its remnants were still howling among the tree branches as I walked through the woods to check on some remote trail cameras. The streams were full with water and many trees in the forest had blown down, some across the trails. I discovered the trees were not the only things damaged. There had been a different kind of recurring “storm” in one location. I walked off the trail through the brush toward it. My destination was a vernal pool in a remote area of Science Center property. An unusual story had unfolded here earlier in the year involving a chicken carcass and a coyote. I had placed the chicken carcass out as bait and captured some interesting pictures over several weeks. This time nothing had been put out to draw an animal to the area, or so I thought. As I pushed through a stand of young hemlock trees I could see the rain had filled the vernal pool half full of water. I walked to the tree where the trail camera was and came to a halt. Something was wrong. The clasp to shut the camera had been opened and the batteries removed! My first thought was that someone had walked through the woods and vandalized the camera, an idea I quickly discarded. Most people photographed by the trail cameras are unaware of them or simply wave and say “hello” once they realize it’s there. I closed the camera and found my first clue; the motion detector’s plastic covering was punctured.
The second clue lay around my feet. My feet disturbed the leaves just enough to revel the batteries. I searched through the leaves and debris and found all of them. They were dirty but otherwise fine. I had unknowingly received an additional clue weeks earlier when the same camera was found on the ground and the strap that held it around the tree was found twelve feet away. That time the culprit was a black bear.

I experienced déjà vu as I stood looking at the camera on the ground and the batteries in my hand. I thought a black bear might also be responsible for the damage this time. I took the broken camera to my office and looked at the images. Sure enough, it showed a black bear yearling energetically investigating the camera. Black bears are curious and investigate novel objects. Apparently the camera interested this bear. It flashes an infrared light whenever there is nearby movement and takes a picture. Perhaps it might rouse a bear’s curiosity to investigate but the yearlings and their mother hadn’t showed much interest in the camera before September. When I looked through the images, this bear was intent on the camera and moved it back and forth triggering the camera to take distorted images of the ground, its fur, its face, its mother, and its sibling from numerous angles.

This young bear was investigating a novel object by smelling it, “manipulating” it with its paws, and finally by trying to chew on it. I thought the bear would lose interest after its first camera encounter. But how wrong I was. This behavior happened again four times during one week in October. Each time the bear would paw and wrestle with the camera anchored to the tree. The last day of images was October 21. The bear must have accidentally triggered the camera latch to open. Once opened it was only a matter of time before the yearling pawed the batteries loose causing the camera to stop taking pictures. There were no pictures of a bear’s mouth or teeth, but the puncture mark in motion sensor covering must have been another way it examined and “tested” the camera. I thought the camera could be sent off for repairs and wondered if I would have to stop gathering images from that location. I was more than just curious now. I was also feeling a bit stubborn about keeping a camera at the vernal pool. I moved a camera from a different location to the study area, but enclosed it in a protective metal case and secured it to the tree with a sturdy wire cable. Maybe this might prevent the black bears from becoming too zealous in investigating the camera and I could learn what might happen before they denned for the winter. We’ll see what the future brings.

January 29, 2018

Stories to Tell - Late Night Swim

By Eric D'Aleo

Have you ever taken a late night swim? Maybe the sweltering summer heat was so bad one night that it was the only way you could cool off and get a good night’s sleep. Maybe you forgot to bring a bathing suit and went swimming in your skivvies or au naturel, grateful for the cloak of darkness. But what would you think about swimming in a New Hampshire pond on a late April night? Not enticing? Apparently it is to a black bear, because that is exactly what happened in a vernal pool on Science Center property.

The air temperature that night was 57 degrees Fahrenheit, not exactly warm, but the water must have been colder. Twelve days before the image was taken, the surface of the vernal pool was frozen, so it was probably a cold, but invigorating swim. The images show the black bear leisurely swimming around as if a cold late night bath was a routine event. I was surprised to see when I looked at the images how much the vernal pool’s depth had changed from September to April. Most vernal pools are quite shallow, ranging from several inches to a foot deep. Yet this pool was quite deep. In September the ground was completely dry. Over the winter it filled with snow and then with spring rains so that by April the pool was about four feet deep. The bear left after a few minutes, perhaps in search of food or other reasons only it knew.

Besides being a spa for bruins, vernal pools serve as important habitat for a variety of wildlife. White- tailed deer, raccoon, bobcat, red fox, grey fox, and a barred owl have been spotted by the trail camera. A number of smaller animals the camera has not seen use this vernal pool as well. Amphibians such as spotted salamanders and wood frogs breed and raise their young in these temporary water bodies each year. Invertebrates, like fairy shrimp, caddisflies, and mosquitoes also use vernal pools to live part of or their entire existence here. Each of these animals is in a race against time before the pool dries up. Amphibians need to grow and undergo metamorphosis to finish their development to survive the transition to land before the pool dries up. They will return to the same location as adults to breed each spring. The fairy shrimp operate on an even faster schedule. They complete their development in forty days, breed, lay their eggs, and die before the pool dries up. Their eggs will survive without water until the following spring, when the pool fills up, and the bruin and the shrimp share the water once more.

September 18, 2017

The soft hues of fall (maple leaf viburnum and hobble bush)

By Eric D'Aleo, Naturalist

Walk through any forest in the northeast in the fall and you are sure to be struck by the brilliance of the colors of the foliage. Many visitors to New Hampshire look forward to mountain ranges robed in various shades of bright colors or search for scarlet-leafed maples along the back roads of small towns. When people walk the trails throughout the state their gaze is often pulled skyward to look at the gold of the aspens and birches, the orange of the oaks, and the red of the maples. However, do not forget to search beneath the brilliant colored canopy for the softer and more subtle hues of the season.

The maple leafed viburnum is a shrub often mistaken for a young red maple tree because its leaves have a similar appearance. A mature plant may reach a height of three to six feet and is often found in the shade of upland forests consisting mainly of beech and maple. In the fall this shrub’s foliage comes in various pastel shades of pale yellow, light pink or a deeper rose color. Often these colors are on several leaves of the same plant or all on the same leaf. The fruit turns a dark blue and is eaten by turkeys, robins, cedar waxwings, flickers, bluebirds, cardinals, flycatchers, thrashers, thrushes, and woodpeckers. In the spring and summer the leaves are a larval food source for the spring azure butterfly and the flowers are a nectar source for the golden-banded skipper.
Maple leaf viburnum
flickr/Katja Shultz
Another understory shrub often overlooked until it “trips” you is hobble bush. Also known as witches hobble the plant is found in rich, moist, wooded areas. The shrub can grow to a height of six to twelve feet and has the ability to root when a branch bends down and touches the ground. This creates dense thickets of plants that make traveling through them difficult. Tripping hazard aside, the shrub’s leaves turn a burgundy to dark plum color in the fall. If the central portion of the leaf still remains green it reminds me of a sliced kiwi whose colors are reversed. The berries also ripen in the fall, changing color from red to dark blue and may be eaten by ruffed grouse, cedar waxwings, brown thrashers, squirrels, and chipmunks. So don’t overlook these lesser known fall color artists, look for their softer hues hidden in the forest and you will be rewarded.
Hobble bush
flickr/US Fish & Wildlife Service

August 14, 2017


Martes pennanti 
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Mistelidae
Genus: Martes
Species: M. pennanti

Fast Facts:
Lifespan: 3-4 years in the wild
Size: 31-47 inches in length, weight 4.5-12 pounds
Offspring: 1-4 young
Status: Populations have recovered from extreme lows in early to mid-1900

What do fishers look like and what animals are their relatives? Dark brown to black in color with a silver tinge to the head and shoulders, fishers are medium-sized mammals similar in size to a fox. Fur tends to be softer and darker in females. Short legs bring them close the ground and they bound with hind paws landing in the place of the front paws, leaving sets of two foot prints side by side. Male fishers average about 10 to 12 pounds but definite sexual dimorphism is evident, with females being a little over half the weight of males. Fishers are members of the family Mustelidae, with relatives being weasels, martin, mink and otters.

What kind of habitat do fishers favor? Fishers prefer continuous forest with a thick canopy, translating in the northeast to dense lowland coniferous forests or a mixed forest of conifers and hardwoods. In distribution, fishers are found in southern Canada, New England, New York state and several other northern states. Home range varies from a little over two to 15 square miles depending on the quality of the habitat.

What do fishers eat? Fisher prey upon snowshoe hare, squirrels, mice, and birds, but perhaps their most intriguing catch is the porcupine. Although not immune to porcupine quills, the fisher has a hunting technique that results in it getting few quills. Using agility to its advantage, the fisher circles the porcupine, looking for opportunities to bite at its unprotected face, while staying away from its powerful tail. Even if the porcupine tries to climb a tree, the arboreal fisher can climb above it and threaten it back to the ground. After about one-half hour, the porcupine may be weakened enough for the fisher to flip it over and attack the ventral side, which has no quills. Porcupine quills rarely cause infection in fishers and accidentally ingested quills often end up in fisher scat! Fishers will also eat carrion. It is unusual for a healthy adult fisher to become prey itself.

Fun Facts! 

  • Do fishers eat fish? Although they will readily eat fish, individuals rarely, if ever catch them. In his comprehensive reference book, The Fisher, Roger A. Powell concludes that the best source of the name was early settlers who noted the similarities between the fisher and the European polecat. Other names for the polecat were fitch ferrets, fitchet, fitche and fitchew – not a big leap to the name “fisher.” 
  • In New England we commonly hear this animal being called a “fisher cat”, a confusing label since fishers are not in the cat family. 
  • Active day or night, fishers are more nocturnal in proximity to people. 
  • What about those screams in the night? Those loud calls are probably porcupines or perhaps owls or foxes rather than fishers. 
  • Now, what about fishers being responsible for the disappearance of domestic cats? Fishers can prey upon cats, but Great Horned Owls, coyotes and cars take a more significant toll. Keeping cats in at night is a good solution.

July 31, 2017

2017 Breeding Bird Census Results

Since 1977, Senior Naturalist Dave Erler has conducted a census in early June of bird species that nest on the Science Center campus. The census is done primarily by ear, listening for territorial songs of male birds, indicating probable nesting. The census gives us a snapshot of the bird population by doing the review on approximately the same date each year. This year we held the census on June 10.

The zones referred to below roughly correspond to: Zone 1 – 30 acres that make up the primary use areas (buildings, exhibits, fields etc.); Zone 2 - +/- 100 acres of forests partly logged for forest management in 2016; Zone 3 - +/- 100 acres of other managed forest area.

We saw a total of 46 individual species and 113 individual birds. See the full details of species and location.