FJ:4 SOCIAL BEHAVIOR AND PHENOLOGY
Date: February 20, 2021
Observation Period: 2:15 p.m. - 3:50 p.m. (1 hour 35 minutes)
Location: Burlington Waterfront Park
Weather: 26 degrees F, Broken Clouds, Wind-4 mph
Habitat: Recreational trail along Lake Champlain shoreline with adjacent manicured landscape of grass and trees.
Date: March 9, 2021
Observation Period: 2:35 p.m. - 4:10 p.m. (1 hour 35 minutes)
Location: Burlington Waterfront Park/Perkins Pier
Weather: 40 degrees F, Partly Sunny, Wind-2 mph
Habitat: Recreational trail along Lake Champlain shoreline with adjacent manicured landscape of grass and trees. Perkins Pier Marina area.
I was interested in seeing Common Goldeneye so I chose this area for the journal. Common Goldeneye breed mainly in the boreal forests of Canada and Alaska. Their urge to migrate is regulated by the circannual cycle, an internal yearly body clock. They are one of the most abundant migratory ducks wintering on Lake Champlain from approximately October until April. I saw a total of 42 Common Goldeneye, however, only seven were close enough for me to observe their behavior, though too far away for vocalization. A group of six males and one female were actively feeding not too far from the shoreline, but there was no access directly in front of them so from my position binoculars were needed. These are diving ducks and spend their time foraging underwater, usually farther from shore than dabbler ducks. From my observations they spent approximately 30 seconds underwater before surfacing nearby, and most appeared to dive around the same time. Their diet also changes seasonally from aquatic insects and plant material in summer to crustaceans, mollusks and small fish in winter. Basically, they all stayed fairly close within the group, and the female was either alone or with at least two other males nearby so it didn't appear as if she had chosen her mate. Another form of behavior within this cycle is courtship display. Before the birds return to their breeding grounds they form pairs. During courtship the male stretches its head backward with the bill pointed up. I saw one male display this behavior and two other males repeatedly thrusting their head forward, but not back with bill pointed up. My second observation period on a different day occurred at a later time in the day, around 4:00 p.m. I observed 32 Common Goldeneye in a group. As part of the circadian rhythm these birds were not actively feeding and seemed to be settling in for the night, just floating on the water, ready to rest and conserve energy.
I observed male Mallards and male Goldeneyes in breeding plumage on this outing. The colorful plumage can influence a female's choice of mate and may indicate a sign of good health. The iridescent green color on the Mallard's head and neck was more noticeable than the green/black head of the Common Goldeneye. Another area of iridescence was the blue speculum bordered in white on the Mallard. (The Common Goldeneye speculum can only be seen when the bird is in flight.) These structural iridescent feather colors are formed by melanosomes in feather barbules. Iridescent sheen color in feathers has been traced back to the fossil remains of Microraptor.
During the second outing the weather was warm enough to melt the remaining snow in certain areas. The Mallards took advantage of the muddy exposed grassy areas to feed, and they were feeding so intently that they were not wary of humans nearby. A few could be observed nudging another away from their desired spot. Their long legs positioned near the center of their body allow them to maneuver on land whereas the shorter legs near the rear of the body in the Common Goldeneye make land movement more unwieldy.
https://www.nsf.gov/news/news_summ.jsp?cntn_id=123392
https://www.allaboutbirds.org/guide/Common_Goldeneye/overview
PISHING:
Date: March 11, 2021
Observation Period: 9:00 a.m.– 11:00 a.m.
Location: Upper LaPlatte Natural Area
Weather: 45 degrees, Partly Sunny, Wind-14.5 mph
Habitat: Trail within a floodplain forest restoration area, crossing the LaPlatte River and opening onto a hayfield.
The focus of this outing was to practice pishing. Apparently, it works best with passerines, however, the subjects were limited here. Several attempts along the trail were unsuccessful in eliciting any birds. Four Black-capped Chickadees were seen together feeding and darting about in the bushes, but they were so preoccupied that they basically ignored the varied pishing sounds. They didn't come closer and no additional bird appeared. Also, the birds were in the open and could see my presence. This wasn't the ideal situation for pishing since the point is to elicit unseen birds.
There appear to be several theories as to why birds may respond to pishing. One main theory is that it is a behavioral response, and the sound is like an alarm call for birds to flock together to defend against a predator. Another theory is that it arouses a bird's natural curiosity. It has also been suggested that the sound may resemble insect noises. Whatever the reason, it does appear to work. I found it interesting to read that birder extraordinaire, Pete Dunne, has developed and teaches thirteen different pishes consisting of hisses, whistles, chips, squeals, kisses and thumps.
As an aside unrelated to this particular outing, pishing did work for me. On March 18 while waiting at the dentist's office, I decided to walk around the edge of the parking lot. In front of some pine trees and with a bird feeder located beyond, I pished and three Black-capped Chickadees and a Dark-eyed Junco popped out of the trees. It took them less than a minute to investigate and then they flew to a nearby area.
https://compleatnaturalist.com/product/the-art-of-pishing/
Species List: 2-20-2021
5 Mallard
3 American Black Duck
42 Common Goldeneye
13 Common Merganser
10 Rock Pigeons
3 Ring-billed Gull
2 Great Black-backed Gull
4 American Robin
Species List: 3-9-2021
18 Mallard
32 Common Goldeneye
11 Ring-billed Gull
11 Common Merganser
2 Rock Pigeon
Species List: 3-11-2021
2 Turkey Vulture
1 Downy Woodpecker
2 Hooded Merganser
28 American Crow
4 Black-capped Chickadee
1 Common Raven
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