March 29, 2023

Field Journal Mar 28 Sean Devine

Start and End Times: 4-5:30pm
Date: 3/28/2023
Location: Charlotte Wildlife Refuge, Charlotte Vermont
Weather: Clear, 45F
Habitat: Mixed hardwood forest, with some surrounding houses
Species Observed: Turkey Vulture, American Kestrel, Canada Goose, Tufted Titmouse, Black-capped Chickadee, Red-winged Blackbird
The winter residents I observed were the Tufted Titmouse, Black-capped Chickadee, and American Kestrel. These species forego migration because their ecological niche allows them to remain all year. For example, a bird that only eats insects might move south in the winter so it still has a food source. Tufted Titmouse and Black-capped Chickadees can live off of seeds and other winter foods, so the time and energy of migration is not necessary. American Kestrels feed on other birds, so it can stay in the winter and prey on other winter residents. Having a food source available is only part of the problem, however, as these birds require multiple behavioral and physiological adaptations to survive colder months. Black-capped Chickadees, for example, cache food in the winter and remember where it is. They also have adaptations against the cold, including controlled hypothermia at night. All of these birds are also most active at warmer times of day.
The migrants I observed were Turkey Vultures, Canada Goose, and Red-winged Blackbirds. All three of these species are very short-distance migrants. Many Vermont geese only migrate to southern New England, while Turkey Vultures migrate to the central-Atlantic. Red-winged Blackbirds migrate short distances, nearly being a resident species, but many northern individuals do fly all the way to the southern US. These birds migrate to follow food sources, and are now starting to come back as winter ends. Snow is melting, the ground is softening and certain food sources are appearing again. Red-winged Blackbirds, for example, feed on seeds and waste grain which may be easier to find as spring starts. I didn't find any obligate migrants, but if I did there would be certain advantages and disadvantages to arriving this early. An early arrival might mean a head start on the breeding season, or easier foraging with less competition. On the other hand, freezing temps are still occurring and late winter weather could still occur and put early arrivals in tough positions.
Assuming migrations on the longer side, we could say the Red-winged blackbirds flew 800 miles from their wintering habitat. The Canada Geese could have travelled around 190 miles. The Turkey Vultures could have flown around 600 miles. That results in a total flown distance of 1590 miles.

Posted on March 29, 2023 06:46 PM by sedevine sedevine | 6 observations | 0 comments | Leave a comment

March 19, 2023

Field Journal 4 Mar 18 Sean Devine

Start and End Times: 4:30-6:00pm
Date: 3/17/2023
Location: Crow Hill Nature Preserve, Easton Connecticut
Weather: Clear, 50F
Habitat: Mixed hardwood forest, with some surrounding houses
Species Observed: Red-shouldered Hawk, Eastern Bluebird, White-breasted Nuthatch, American Goldfinch, Tufted Titmouse, Black-capped Chickadee, Red-bellied Woodpecker, Downy Woodpecker, American Crow, Canada Goose, Northern Cardinal
All of the birds I saw here were first spotted from the noise they were making by communicating. All of the species were also concentrated close together, as about 90% of the individuals I saw were in the first quarter of my walk. The high level of activity in such a small area allowed me to witness some interactions both within and between species. For example, I saw two Downy Woodpeckers chasing each other from tree to tree, with one of them making loud calls in flight. I don't know for sure what it was about, but my guess would be fighting over territory. Another interaction through audio cues was the Canada Geese I saw in the distance. They were foraging mostly silently, until one started calling and the whole group joined in and took off. it's possible this was a communication of some sort of threat. I also saw a Red-shouldered Hawk which was making frequent loud calls from a treetop. This was likely some sort of territorial call, but a side affect seemed to be a lack of bird activity in the immediate vicinity of the hawk.
Two birds with very different plumages I saw were the Tufted Titmouse and Eastern Bluebird. In a forest of gray and brown with fading light, the bluebirds were much easier to spot than the titmouses, who were easy to hear but not see. The blue backs of the bluebirds were especially noticeable in flight, whereas the Tufted Titmouse plumage blended in with the gray tree tops they were singing from. The advantage of the bluebird plumage would likely be sexual selection, as a display of color is more likely to attract a mate. The titmouse might still show sexual selection, but the plumage lends itself more to camouflage than some more colorful birds.
An individual I was able to closely watch the behavior of was the Downy Woodpeckers, who seemed to be very active. 3 of the 5 were pecking at trees and foraging for food, while the other 2 were flying after each other as mentioned before. They're activity makes sense given the time of day, as they are not nocturnal birds but do become more active at dusk. It also makes sense given the time of year, as the weather is warming and breeding season is well underway.
My attempts at spishing did not achieve much besides scaring birds away, which was likely due to me being unable to get close enough. In general, spishing works because it imitates the communication of songbirds. Even if it doesn't match the call of a species, birds still recognize it as another bird trying to say something, such as a threat being near, which sometimes leads to birds getting closer to evaluate the situation.

Posted on March 19, 2023 12:16 AM by sedevine sedevine | 11 observations | 0 comments | Leave a comment

March 01, 2023

Field Journal 3 Feb 28 Sean Devine

Start and End Times: 12:30pm-2:30pm
Date: 2/25/2023
Location: Sucker Brook Hollow, Williston Vermont
Weather: Clear, 13F
Habitat: Mixed hardwood forest with some sections dominated by conifers
Species Observed: Black-capped Chickadee, Tufted Titmouse
The day I was out had very low temperatures, with a high of 13F. Despite this, the two species I observed were fairly active. The Tufted Titmouse I observed were in a fairly dense stand of trees, close to the trunk. These birds can utilize their environment to stay out of the wind, in trees or other crevices that occur naturally. Additionally, like all birds, their feathers are key in insulating from the cold temperatures this time of year, trapping warmer air close to their body. Some research I did reveals they also survive the winter by hoarding food in the fall months.
The other species I saw was Black-capped Chickadee, which were similarly remaining in a dense hemlock stand to avoid the wind, using its feathers as insulation, and storing food for the winter. Further research showed they actually go into a nightly hypothermia to conserve energy, reducing their temperature in a controlled manner to about 15 degrees below normal. This allows them to save limited energy stores instead of using them to maintain a high body temperature.
Both birds seem to be most active at this time of day when it is warmest, using the opportunity to stay warm and seek food. To stay warm at night, they seek sheltered roosting spots, such as a tree cavity. Both birds' diets this time of year consists mostly of seeds, supplemented by any nearby feeders. On the property, bird activity was highest in areas with younger trees/shrubs mixed with older ones, but some activity was also seen on edges near neighboring properties.
In keeping an eye out for snags, I didn't notice a large amount of them, perhaps because much of the forest appears younger and some sections owned by landowners looked to be managed forests. The biggest snags I saw were large beech which had fallen victim to beech bark disease. Some of these had entire large cavities in them, but many had large rectangular Pileated Woodpecker holes. Other snags I observed were mostly pine and hemlock, which had smaller holes, possibly from Downy or Hairy Woodpeckers. I saw no correlation between the abundance of snags and bird abundance, but I was on the property at midday, not at dusk. Tapping on snags didn't cause anything to emerge from cavities, but again, the time of day wasn't one where I'd expect that. Snags are important due to their role as a habitat requirement for dozens of Vermont birds. As evidenced by some of the holes, they are vital as a food source for some birds including woodpeckers, and for other species they serve as a place for shelter or nesting.

Posted on March 01, 2023 06:18 PM by sedevine sedevine | 2 observations | 0 comments | Leave a comment

February 19, 2023

Field Journal Feb 20 Sean Devine

Start and End Times: 3:00pm-5:00pm
Date: 2/15/2023
Location: Milton Town Forest, Milton Vermont
Weather: Partly Cloudy, Mid-40s, 30 mph wind gusts
Habitat: Mixed hardwood forest, shrubs and small trees near marsh
Watching the movement of a Black-capped Chickadee, I could see that its flight was adapted to take off relatively quickly, and maneuver in tight spaces. This makes sense given their behavior and habitat, which often has them maneuvering through the branches of small trees and moving quickly to avoid predators. Physically, I imagine their relatively small size, including their wings, allows for this agility. The individual I was watching hopped from tree to tree, but when it did fly for a more extended period of time I could see its flight pattern was not very straight, it instead went up and down somewhat erratically.
I also saw about 4 American Crows flying relatively high above the open marsh. In their flight, they flapped fairly quickly for a few moments, before gliding for a bit. The ones I saw were flying into the wind, so I imagine they had to work harder and flapped more to continue in that direction. In terms of direction, they were moving one way but they weren't going straight. Some would occasionally veer off 45 degrees or ever circle around. The only other bird I got to see fly was a Hairy Woodpecker, but as it was busy pecking a tree I didn't see much. It was able to take off from where it was clinging on and ascend to another hole higher up the tree. This takes a lot of energy and requires wings which can immediately produce enough lift to overcome gravity. I also got to see it use its tail feathers to keep itself anchored when it was standing still pecking a hole. I didn't get to see any birds fly for long enough or distinctly enough to learn how to identify them from their flight, but I can imagine how one could at least deduce the type of bird from the flight. For example, the chickadee's quick, agile flight between trees would certainly rule out less agile birds.
I got to see or hear 4 birds, but I probably would have found more in different conditions. It was late afternoon, which can be a time of bird activity, but I was just a little too early because I only started hearing a bunch of chickadees in the trees as I was leaving around 5:15. Going in the morning would be more ideal, but if I do go in the afternoon it would have to be a bit later. A bigger factor however would probably be the wind. The weather showed 30 mph gusts, which were occurring quite frequently and were more than enough to shake the trees violently. This wind probably encouraged at least some species of birds to take shelter. The warmer temperatures might have increased activity, but it was still certainly winter and snow covered the ground. Finally, I noticed that I saw more birds on edges than I did in the interior of the forest. This could be many things, including easier visibility and the more common species (like chickadees) living on edges.

Posted on February 19, 2023 07:10 PM by sedevine sedevine | 4 observations | 0 comments | Leave a comment

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