Marvelous mammals, part 2 – at parks and reserves

Some of the mammals that I see when visiting parks and nature reserves are the same as my yard visitors (see the previous blog). For example, on a recent walk at a wetland area, an Eastern gray squirrel (Sciurus carolinensis) decided to engage me in conversation as I walked under its tree. It would descend a few feet, look at me intently and utter sounds.

 

I responded (in English) and it would look at me quizzically, ascend the tree and then turn around to come closer again.

This went on for about 10 minutes. When I walked further on, another squirrel was perched on a small limb eating a snack and stopped to observe me as I passed under its tree. There was some communication going on between us, although I confess that I wasn’t sure what she was saying.

 

Other mammals I only see rarely in my yard but a little more often in public natural areas. An example is the groundhog (Marmota monax), which also goes by the common name of woodchuck.

Last year, I had a groundhog come up on my front porch where I had a container garden; it was really enjoying the tomatoes to my surprise! More recently, a friend and I were stopped on a road through agricultural fields when a groundhog emerged from a culvert. The animal looked around at its leisure and then eventually retreated to the culvert when our car began moving forward.

 

And then there are mammals that I don’t see at all where I live since my yard is not close to wetlands, bogs or rivers. A recent trip to the North Carolina (NC) Atlantic Coast gave me a chance to see a muskrat (Ondatra zibethicus), which some Native Americans called a musquash. Fellow birders alerted me to its presence as it was sitting at the edge of a small pond where they had been watching water birds.

The muskrat can be distinguished from the nutria, which looks very similar, by a couple features explained to me by a park employee. The muskrat has much less prominent whiskers than the nutria and its tail has somewhat flattened sides. Overall, they are smaller than nutria. I do think a muskrat I saw in our nearby Haw River was fairly big.

Muskrats dig burrows into river banks and the sides of ponds and canals; sometimes, they also will construct a large lodge atop mud and roots in marshes. Their babies are born blind and hairless; as they mature, they get either brown (70%) or black fur (30%).

At the coast, we also got to see the nutria (Myocastor coypus), swimming at the edge of a wetland near a road. These rodents are native to South America and were introduced to the USA in the 1800s; they are now found in 22 states. In North Carolina, they are only found in the coastal and Eastern parts of the state.

 

 

Nutrias are larger than muskrats and smaller than beavers; their very white whiskers are distinctive.

They construct floating platforms with vegetation on which they rest, groom and eat. They may live in colonies of up to 15-20 individuals. Their eyesight is poor and they sense danger through their sense of hearing.

They are considered a nuisance animal as they can convert marshes to open water and are known to eat farmers’ crops. Their numbers have partly been kept down in NC because of hunting (trapping) and partly because they have an elevated mortality during cold winters, to which they are not adapted. I’m guessing that the nutria will not have an easy future in this state.

Another water-loving mammal that has had problems with humans is the North American beaver (Castor canandensis). One of my book clubs is currently reading Eager: The Surprising, Secret Life of Beavers and Why They Matter by Ben Goldfarb. He details how they were trapped and killed by the millions when Europeans arrived in North America and how this changed much of the landscape throughout the country – often causing a deteriorating environment.

In NC, the last native beaver was trapped in 1897; we only have them now because the NC Wildlife Resources Commission reintroduced beavers in the 1930s. Still, these mammals often face negative reactions from human neighbors, who frequently have them “removed”.

Goldfarb details different ways in which humans and beavers can peacefully co-exist. He notes one way (among many others) in which they can be quite beneficial: “As the climate warms, more precipitation is falling as rain rather than snow. Instead of remaining in snowpack and gradually melting throughout the course of the spring and summer and fall and keeping rivers and streams wet well into the dry season, now all that precipitation is falling as rain. Any entity that can store water on the landscape, that can keep water high in some of these mountain headwaters in places like the Cascades or the Sierra, becomes incredibly valuable. What stores water better than a beaver? Basically nothing.”

Beavers live in a several places not far from my home. At the Sandy Creek Park, the beavers were posing a challenge as their dams had led to flooding of a paved path which makes the park more accessible to people in wheelchairs, with strollers, etc. Beaver deceivers (pond levelers) have been installed and the pond level has decreased; the beavers appear to be adjusting to the new situation.

At another site, neighboring home-owners took sides on whether the beavers were a community benefit. Some were in favor of the beavers and hired wildlife biologists to help them figure out how to install beaver deceivers. Others opposed the mammals’ presence (defacing a fan’s tribute to the beavers on a bridge) and a homeowners association had a beaver lodge destroyed and the wetland drained in order to drive the beavers away. The variety of wildlife in the area immediately declined greatly.

 

As the NC Wildlife Resources Commission notes: “By damming streams and forming shallow ponds, beavers create wetlands. These wetlands provide habitat for a tremendous diversity of plants, invertebrates, and wildlife, such as waterfowl, deer, bats, otter, herons, songbirds, raptors, salamanders, turtles, frogs, and fish.”

Fortunately, one lodge was left there and a pair of beavers, who mate for life, is still in residence. Their lodge is currently also being used by another water-loving mammal that I love to see — the American river otter (Lutra canadensis lataxina). On a recent very overcast day, I was lucky to see three of them.

These beautiful mammals have also lost much ground in the USA due to trapping, wetland drainage and water pollution.

The otters look for food in the beaver-maintained pond, diving into the murky water and coming up covered in mud. This requires vigorous grooming, which they do sitting on the lodge. On the day I saw them, three were busy with this task. One pair helped each other.

A third otter was busy cleaning him/herself without help. It was interesting to see how the sleek muddy fur was licked clean.

S/he also used the lodge higher up as a toilet area. Geese have had a nest atop the lodge so it has proved useful as a multi-functional structure.

Otters are perhaps more popular than groundhogs, muskrats and beavers because they can be playful and people enjoy watching them. The restoration of otters throughout NC also benefited the state in another way – river otters captured in the Eastern part of NC were donated to the state of West Virginia and NC received wild turkeys in return, leading to restoration of a population of these wild birds in the state.

My biggest treat lately has been watching Atlantic bottlenose dolphins (Tursiops truncatus) off the NC coast. They swim close enough to shore that you can at least see their flippers emerge from the water. While other birders on our trip were intent on identifying avian species such as gannets, gulls, pelicans, etc. I was busy photographing two pods of dolphins that were swimming by.

These intelligent animals form groups of about 10-25 individuals; I saw about 5-10 swimming near one another. That was exciting; many years ago, I had gone on a boat trip with my nephew to see dolphins, but we failed to see any on that trip.

I discovered that there are certain dolphin families that inhabit the waters of NC’s Outer Banks: Onion and his family summer around Nags Head and winter around Beaufort. Since we were at Nags Head in the winter, the dolphins I saw may have been a different family.

A few animals that I’d hoped to see on my trip to the Outer Banks in January were the black bear, coyote and red wolf. The man who organizes the annual black bear festival in Plymouth told me that it was unlikely we would see bears since the mothers would be in their dens and other bears would also not come out much with the sudden fall in temperature we had that weekend. He was right and we also didn’t see coyotes or wolves. I did discover some scat, indicating some mammal had been on the road. Perhaps I’ll be lucky and see one of the resident coyotes at the nature reserve where I volunteer soon; one can always hope!

A bountiful year for seeing Castor canadensis

It has been my privilege to go on safaris in Africa and my outings in nature there resulted in sightings of multiple mammalian species each time. Where I live now, there are also a variety of mammals but I don’t see them often, other than squirrels, chipmunks, deer, opossums and raccoons. I was lucky to see chewed trees as evidence of American beavers’ (past) presence, but I was not seeing members of the Castor canadensis species. Some of the chewing patterns on the trees were interesting though.

I saw my first beaver lodge at Brumley Nature Preserve South in early 2016 and had the good fortune to get a quick glimpse of a beaver there. (Before that, I had seen them in zoos.) Then I began noticing beaver dams more often on walks, like the one below near the Haw River. So for my first long blog of 2019, I’d like to share with you how 2018 became my bountiful beaver year.

In the spring, a friend told me about a creek where beavers’ dams had resulted in marvelous wetlands along some nature trails. Their handiwork at Pokeberry Creek was appreciated by a considerable number of nearby residents, who were pleased with an increasing number of waterfowl and other birds at the wetlands, as well as otters.

 

They spoke about the benefits of beavers’ presence, such as the increased biodiversity, improved water quality and more opportunities for wildlife viewing, and celebrated their arrival. Some birding groups began leading walks there to view the numerous songbird and other avian species.

For me, the chance to see the beavers in action was wonderful. One day, I saw an adult chewing branches as part of its meal; it was quiet and didn’t seem disturbed to have me nearby watching.

On other occasions, I saw individuals bringing reeds back to a lodge, presumably to feed young ones left at home. (The offspring may stay with their parents up to two years.)

As beavers are mostly crepuscular, visiting at dusk offered a good chance to see them at work felling trees for their dams and lodges. It struck me that when I had observed them eating, they were very quiet. When they were working to cut trees down, however, I could hear them chewing very loudly.

Some people living near Pokeberry Creek brought chairs and drinks to watch the animals at work in the evenings and everyone present seemed to be learning a lot about them. Apparently, many people are interested in beavers – the ranger station at the Jordan Lake Dam has a taxidermied beaver and information about their lodges on display.

Nature’s aquatic engineers are certainly interesting mammals. North America’s largest rodents can swim underwater without coming up for a breath for some 15 minutes; this is because they slow their heart rate. Their transparent eyelids function as goggles so that they can see underwater.

They build dams to ensure that the ponds in which they construct lodges are deep enough so that the entrance remains under water. When the water is at least 2-3 feet, they will be safe from predators and the entrance to their home will stay ice-free in the winter. If they are in a spot where the water remains high enough all the time, they may forego building dams. At Pokeberry, the animals felt a need to build dams in two places. Research has shown that the noise made by water flowing away contributes to their decisions to shore up dams; they apparently cannot tolerate the sound of running water above a certain number of decibels.

The beavers’ environmental engineering irritated some members of the Home Owners Association (HOA) of a nearby community which is still under development. Some people complained that the water was encroaching onto properties (other property owners were ok with it). The rising waters also sometimes flooded a long walking bridge and a cul de sac. Numerous repairs were needed for the bridge and “opposing” parties emerged.

After the HOA announced a plan to have 35 beavers killed, a petition to save the mammals was begun. Within a few days, more than 3700 signatures had been gathered and the HOA undertook a consultation process with different agencies to explore other options. The Friends of Pokeberry Creek Beavers and Wetlands, in the meantime, put up small barriers so that the waters would not encroach so easily onto the cul-de-sac. They also installed a “beaver deceiver” (a pond leveling device, comprising large tubes inserted through a dam so that water would continue to flow through).

It appears that the beavers found the water flow too noisy, so each evening they would mud up the fencing around the deceiver intake so that no water could enter there. The humans would take away the mud; the beavers would put it back. The humans moved the pond leveling devices to deeper areas, but with heavy rainfall, the waters would rise very high.

Finally, in early autumn, the HOA had much of the wetlands drained. This was done to avoid killing the beavers by driving them further downstream to find another area where they could build dams to establish a new pond territory.

The beavers in a large pond that remains rather full have not moved; they are still felling trees, presumably to reinforce their lodge and to have some food supplies in stock for the winter. They also need to keep chewing as their teeth never stop growing. When they remove trees, they leave stumps of about 6-12 inches behind. I’ve seen some of these tree stumps, such as a tulip poplar, sprouting branches again. So the beavers’ tree clearing does not have the same effect as clear-cutting done by humans.

   

  

I thought that the drained wetlands at Pokeberry Creek might be the end of my beaver observation opportunities, but then I discovered that another wildlife and recreational park was facing challenges from beaver dams. Sandy Creek Park had had beavers some 5-6 years ago and at that time the mammals were removed (killed). The park manager wants to avoid that now if possible, but the dams need to be controlled since they are causing flooding onto paved pathways which help make the park accessible to persons living with disabilities.

A wildlife biologist visited the park to assess the potential success of a pond leveler there; because the pond in question is rather deep, they may have more success with a beaver deceiver. I’m guessing it will also depend on how the noise levels evolve with the new flow of water into the nearby creek. If they can install a silent outflow pipe, the intervention may be successful.

In November, I found that beavers were also busy at a third natural area that I visit often, the Brumley Nature Preserve North. The rodents are busy in two of three ponds there. The volunteer trail steward periodically breaches the dam at one pond so that the water can continue flowing downstream. When the pond water level remains high enough, the beavers seem to be more lax in repairing the dam.

  

At the other pond, the water level has stayed fairly consistent with all the rainfall our area has had in the past months and no beaver engineering seems to be happening there. As there is no obvious stream flowing into that pond, if we have a dry summer, the beavers may have to abandon that home as the pond could dry up as happened during a drought period last year. There was an interesting development at this pond, however. It involved one particular beaver who recently spent afternoons for a couple weeks swimming laps for hours.

I was quite surprised to see him (it could be female but somehow I thought of this individual as a male who was hoping to attract a mate), since beavers often prefer not to be out in the open during the day. He even emerged from the water from time to time, but always on the other side of the pond.

 

It didn’t matter whether the day was sunny or colder, gray and overcast. Sometimes, it seemed that he was taking a quick power nap.

  

The beaver would make small circles, large circles, go to the shore for a quick rest and then resume laps.

One day, I saw him swim toward the lodge and I was able to see inside above the underwater entrance. He didn’t stay there long though and soon came out again to exercise.

This beaver seemed to be quite relaxed, swimming around and around, except for when walkers came by with dogs. He definitely did not care for the canines; when they appeared, he often would begin slapping his large, flat tail on the water and then diving noisily under water before emerging again nearby.

These tail slap warnings and dives showed off his webbed hind paws.

It was interesting to hear how very loud the tail slaps can be. The beaver will also vocalize its distress.

At one point, some visitors to the reserve allowed their dog to jump into the pond and the canine swam close to the beaver lodge. (Dogs are supposed to be kept on leash but a number of pet owners ignore the sign stating this. When I mentioned that dogs running loose also disturb ground-feeding birds, the response was: “Too bad for the ground birds!”) That very much disturbed the beaver, who slapped his tail again and again.

After that incident, I only saw the beaver having afternoon lap sessions a couple more times. He seems to have given up the practice or is now restricting his swims to very quiet times. I can understand if the animal is trying to avoid stress and distress; that’s one reason I go out for nature walks, too. But I was glad he ventured out for a while so I could see him fairly close on several occasions.

Happy New Year to you all – hope your 2019 is happy, healthy and filled with nature’s beauty!