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.

June 9, 2017

Heron of the Night

By Dave Erler

The first time I heard the call of a Black-crowned Night-Heron (Nyticorax nyticorax) I was about eight years old. It was just after an evening of fishing for Black Crappies on a lake in Minnesota. I remember it happened as I loitered along the shore after my father, older sister, and younger brother had all headed back the trail through the woods. A loud guttural “quock” sound came from overhead and although I don’t think I was scared I do know it startled me. I had no idea what made the call. I didn’t hear l that cry again until some 14 years later, but I knew immediately I had heard it before. At that time I was working for the University of Minnesota Extension Service at a summer youth camp near a Minnesota lake. I was with a group 10 to 14-year-old farm kids. The sound scared the bejesus out of some of the kids. They, of course, immediately wanted to know what it. Being the “nature specialist” I suddenly felt pressure to supply an answer. I have to admit I still didn’t know what it was. I knew it wasn’t an owl and I knew it wasn’t the low-pitched “croak croak” of the Great Blue Heron. I responded that it was just the call of a “water bird,” which seemed to reassure the kids that it wasn’t anything too dangerous. That incident gave me incentive to find my set of Peterson birdsong tape cassettes.

Since both times I had heard the sound it was at night, near a lake, clearly came from above, and was similar to the call of Great Blue Herons I’d heard when they were flying overhead, I figured I should start there. Sure enough, the guide with my Peterson tapes listed my options. I picked the cassette with bird calls from Loons and other water birds and slipped it into the tape player. I pushed the button to fast forward, randomly stopped it, and pushed the play button. Low and behold by pure luck the very same call I had heard came from the speaker. I hit the stop button, put it into rewind for two seconds, and the monotone voice identifying the calls put a name to the mystery call.
Black-crowned Night-Herons are small, squat, chubby herons with thick necks, rather large heads and heavy pointed bills. As their name suggests, the adults have distinct well-defined black crowns as well as black backs with contrasting white undersides. Their legs are shorter than the larger Great Blue Herons’ are.  In flight their short legs barely reach the end of the tail. While in the air they hold their heads back against their bodies making them appear to have no neck. Like most herons, they have a rather slow, steady wing beat on broad, rounded wings.
Black-crowned Night-Herons are found across much of North America and on every continent except Australia and Antarctica. Although not as commonly seen as the more familiar Great Blue Herons, Black-crowned Night-Herons are probably the second most common heron in North America. Due to their nocturnal habits they are not often seen. During the day they usually find shelter by perching in trees, hidden among the foliage, often in groups. In the evening and night they forage in marshes or along the edges of lakes and streams. Their dagger-like pointed beaks are serrated, allowing them to snatch and hold slippery prey including fish, crawfish, frogs, tadpoles, and water snails. Once they catch their prey they swallow it whole.
When you visit the Science Center this year make sure to visit the Celebrate Birds Exhibit. The attached aviary will be a “heronry” displaying several species of herons, including an immature Black-crowned Night-Heron. If you visit over the course of the summer you will notice a change as it molts from its immature brownish, streaked feathers to its very different adult plumage. Like most of the birds that live here, this bird is non-releasable. It (he or she – it’s hard to tell) arrived from a wildlife rehabilitation center in Glen Ellyn, Illinois, where it was treated, but deemed non-releasable due to a wing injury limiting its flight ability.

In the years since I first heard those guttural “quock” calls, I still have only seen Black-crowned Night Herons perhaps a half dozen times. But to this day I have yet to hear another one call, but rest assured if I do, I will know what made that sound in the night.

May 10, 2017

Stories to Tell – Guess Who Came to Dinner?

By Eric D'Aleo, Naturalist

We’ve all experienced it. A fresh set of tracks in the snow. The first question you ask yourself is… Whose track is this? This leads to a number of other questions. Where did it come from? Where was it going? What happened here? These questions often remain unanswered unless we can track the animal, we have a camera in the location, and we’re lucky. This is one such occasion with an amazing answer.

It was a cold, late winter morning and a light snow was falling as I plodded through the woods. Occasionally my feet broke through the snow’s crust and I’d sink in up to my calves. “Not a day to skip wearing snowshoes,” I chided myself, but I was more than halfway to my destination. I was eager to check the final trail camera of the day and see what it had recorded over the past month.

I hiked over the last rise and saw the log where I had secured a chicken carcass in February. The location was 15 feet from the camera. I was surprised to find there was no sign of the chicken. It was completely gone. “What took it?” I wondered. I walked over and looked around. No visible signs of feathers or bones, although they might have been covered by the recent snow. The only clues were obscured footprints and marks in the snow I could not identify. It was obvious there had been recent activity but it seemed that the camera might be the only witness. The snow continued to fall as I changed the camera card and headed back to my office to upload the information to the computer.

Once at my desk, the story of the missing chicken and the disturbance in the snow played itself out on my computer screen. The first animals to investigate the chicken carcass were a pair of raccoons. They arrived at dawn two days after I had put the bird out. They sniffed and pawed at the feathers before one took some bites and claimed the chicken as its own. It stood on the frozen body keeping the other raccoon at a distance. This lasted for 30 minutes until they left, perhaps because the morning sun was too bright.

Twelve hours later the two raccoons returned. Again only one animal fed; apparently the larger one was dominant. The second raccoon circled and wandered just out of reach looking for an opportunity to find something to eat. This behavior lasted for an hour before they left. I found this surprising since the time stamp on the last image of the raccoons read 7:20 p.m. They should have had plenty of time for them to continue feeding. The next image held the answer. A coyote came into view 50 minutes later.

The coyote was interested in the chicken but hesitated because of the infrared flash from the trail camera. It paced back and forth and circled the area maintaining a distance of 10 to 25 feet from the bird but never came closer. Then the coyote suddenly left. I stopped advancing the images. This seemed strange. Why didn’t the coyote feed? It seemed rather odd but I had read that coyotes are cautious when exposed to a new or unfamiliar food situation. But what animal was responsible for the missing chicken?

The next images answered my question. Thirty minutes after the first coyote left a second coyote entered the area. This animal was much larger and more confident. It walked directly to the chicken and assessed the situation. In less than two minutes, it determined the camera was no threat, sniffed the chicken, and set to work. It made quick progress severing the chicken from the anchors holding it to the log. Forty five minutes after it arrived, the coyote carried its frozen prize off into the night. I was amazed at how quickly the coyote removed the bird. I was excited to have an answer. But as I looked at the image I realized I had only a partial answer. I now knew what had taken the chicken, but I had no idea what animal left all the tracks and marks in the snow when I checked on the camera. All the images up until this point occurred on ice and a small patch of snow under the logs. When I removed the camera card in the morning, the entire area was blanketed with snow except for the slowly filling tracks. I was so immersed in what was happening I forgot to consider the surroundings. I thought I had an answer to my original questions, but now I realized I had only half the story. So I continued looking through the images.

An hour after the large coyote left with the chicken, a smaller coyote cautiously approached and circled the site from a distance of 30 feet or more. I assumed that it was the first coyote as it seemed to be the same size and exhibited the same behavior as before. It continued in this manner for five minutes and then left. It returned an hour later but only for a minute before it left again.

Four hours later, at 6 am a barred owl landed among the feathery remains. It pecked at the ground for a moment or two and then departed into the early morning darkness. The entire visit took a little more than one minute.

It was now three days after the chicken was initially placed, according to the time stamp on the progression of images, but even though the bird was gone, the site continued to be visited over the next 18 days. Several coyotes, two raccoons, and a gray fox all looked to see if there were any remains worth eating, but all left shortly after arriving.

I paused realizing I still did not have an answer to my second question. How were the markings left in the snow? As I continued looking at the images I noticed snow had covered the ice three days prior. Then the day before I arrived to switch the camera cards the puzzle was solved. Early in the morning a coyote visited the site. It seemed nervous by the infrared flash of the camera but seemed intent on approaching the location where the chicken had been. The ground was covered by several new inches of snow and there were no obvious signs to draw the animal in. Yet the coyote continued to warily approach. I thought that this must be the same coyote that had showed up the first night. It spent 12 minutes trying to overcome its anxiety. The coyote paced back and forth, dug at the snow behind one of the logs, bounded to one side, went back to dig some more, bounded away again, dug a third time, backed away, bit a low hanging branch in displaced frustration, and dug again until it finally came up with a small scrap of food. It took a few steps away, fed, and went back to anxiously digging and backing away for several minutes longer before it eventually left.

I looked at the final camera image of me as I stood at the site, looked at the marks in the snow and wondered what had happened here over the past month. I had to smile at the image of myself as I sat at the computers. I had no idea then of what story the camera would reveal to me that day.