March 23 Broad Meadow Brook Journal 3

On March 23, 2020 from 11:30 AM – 1:30 PM I hiked 4 miles at Broad Meadow Brook Mass Audubon Wildlife Sanctuary to go birding. The weather was cold at a temperature of 29º F with cloudy skies and snow coming from the west. Broad Meadow Brook is a 400-acre hardwood oak and red maple forest located in the city of Worcester, MA making it the largest urban wildlife sanctuary in Massachusetts. One of the most notable features is the Broad Meadow Brook tributary that runs through the sanctuary that acts as part of the headwaters of the Blackstone Watershed. At Broad Meadow Brook 30 species and 383 individuals’ birds were observed at three notable locations which include: Frog Pond Trail, Wilson Meadow Swamp, and Heron Pond.

Frog Pond Trail is a transitional area from oak forest to red maple swamp consisting of vernal pools. In addition, this trail marks the edge between the sanctuary and the surrounding residential housing. Spaced between two radically different habitat Frog Pond Trail acts as an edge habitat for birds. Along the edge thorn bushes and red maples hosted House Sparrows, Dark-eyed Juncos, Downy Woodpecker, Black-capped Chickadee, White-breasted Nuthatch, Carolina Wren, American Robin, House Finches, and Northern Cardinals. The very active mixed flock was all concentrated along a 50 m stretch of the trail with shade provided by the red maples and brush and nearby bird feeders from the surrounding residential housing. Some notable bird behaviors were exchanged between themselves and myself. In the thorn bushes House Sparrows and House Finches were giving audible calls to each other. These birds were evenly spreading themselves apart from one another with some being the aggressor and some being the submissive. This was seen in both male House Finch and House Sparrow where those with the males with the darker red or black chest splotches were agonistic to lesser pigmented conspecifics. However, as I came closer to observe this interaction with the House Finches and House Sparrows a Carolina Wren gave an alarm call. Hiding the wren was alerting all nearby birds of my presence as a possible threat. Giving this alert call to this mixed species flock is a benefit in flocking which allows for increased predator vigilance. Sadly being on the short end of this behavioral stick the Carolina Wren’s alert calls called for the dispersal of this rich flock.

Moving on from Frog Pond Trail I arrive at Wilson Meadow Swamp. Here marks the end of the transition of an oak forest to a flooded red maple swamp and beaver pond. Active beaver and muskrat have built dams and lodges allowing for flooding of Broad Meadow Brook to make an extensive flooded marsh area. This swamp act had standing snags, speckled alder, bigtooth aspen, red maple, and plenty of brush cover. With all of these habitat features this acts as ideal breeding location for Red-winged Blackbird and Common Grackle. Red-winged Blackbirds and Common Grackles were everywhere calling from the sky and perched on every snag. Overcast made it hard to identify each individual, yet there was at least over two-hundred of both species. Preparing for the approaching breeding season both these species are here in large numbers claiming territories and potential mates. This phenomenon can be explained by these bird’s circannual cycles. Circannual cycles control these birds to perform key behaviors throughout the year such as a breeding determined by length of daylight. As spring as arrived officially and daylengths are growing these birds are physiologically responding to this change in daylength and are responding to migrating north to places like Broad Meadow Brook to prepare for breeding. In addition, other species at Wilson Meadow Swamp are present awaiting to breed such as Mallards, Canada Geese, Wild Turkey, Hairy Woodpecker, Blue Jay, Northern Cardinal, Song Sparrow, American Robin, and Red-Shouldered Hawk.

Moving away from Wilson Meadow Swamp I moved to Heron Pond. To get to Heron Pond I trekked over a powerline trail created by National Grid. Along the powerline was short grassland meadows with sweet fern and small gray birch and cherry saplings. Flyover events by American Crows, Common Raven, Pileated Woodpecker, and Mourning Doves were observed here. In addition, an Eastern Bluebird was found perch in the samplings and retreated to the adjacent forest stand we threatened. Later on, I soon approached Heron Pond by going through a Gray Birch stand. Here I tried to use phishing to call in some nearby birds. Phishing mimics a Black-capped Chickadee alert call to a predator making other songbirds take notice of the threat. Phishing worked for me getting the attention of Black-capped Chickadee, White-breasted Nuthatch, and American Goldfinch.

Moving on I approached Heron Pond which is a manmade isolated pool which acts as a rookery site for Great Blue Herons. Sadly no herons were seen but Wood Ducks, Canada Geese, Hooded Merganser, Mallards, Eastern Phoebe, Northern Mockingbird, and Coopers Hawk were seen. The male wood ducks were stunning showcasing bold patterns of a green head with hints of yellow and red to advertise the reproductive health of these breeding males. In contrast, the female wood ducks were dull showcasing cryptic coloration to reduce threat of detection by predators when they nest later on in the season. These sexual dimorphic traits better suite the different roles of these wood ducks. However, in some species such as Eastern Phoebe do not exhibit this sexual dimorphism in plumage. Both male and female Eastern Phoebes have a black back and white belly possessing counter shading. Countershading is a protective plumage that dark dorsal plumage is cryptically blending into the ground and the lighter ventral plumage is cryptically blending into the sky allowing for the avoidance of detection. Unlike the Wood Ducks, the Eastern Phoebe priorities the need for avoidance rather than for reproduction and cryptic coloration.

This was a great day of birding showing the readiness for the breeding season seen in the growing number of bird species and behaviors. Most notable for me out of this experience was the Cooper’s Hawks. These Cooper’s Hawks have been returning to this location annually for a breeding site. Usually I am here to see them rear offspring, yet now I was able to see them cooperate building a nest. Similar to these Cooper’s Hawks building a nest the birds of Broad Meadow Brook and the northeast are in the early portion of the breeding season waiting for the rearing of offspring. I cannot wait to see and observe this entire breeding season from nest to fledging.

Species Count