Duck Tallies Are In

For the third year, we’ve conducted a fall waterfowl migration survey on Jacobs Pond, and for the third year, we’ve been surprised by some elements of the count. Here are some raw numbers:

2015 Effort and Conditions:

In all, we made 36 counts, 1 from each observation point for 18 weeks. In general, surveys of this type in the northeast end when the water body freezes over. In 2013, the pond was frozen for good around December 15; in 2014 and 2015 ice formed in small amounts on several occasions, but the pond never froze over. Air temperatures generally declined over time, but never reached the point of freezing during the counts. The high temperature was 67 degrees, the low 33. One week’s counts were conducted in light rain. Generally, winds blew out of the north and northwest, ranging from 5 to 20 miles per hour. Visibility was only impinged on one occasion, due to low-lying fog. All observations took place between 7:55 and 8:37 a.m.

Results

Forty-four species sightings were made between September 1 and December 28, 2015. Those forty-four sightings came in eight species: Bufflehead, Canada Goose, Hooded Merganser, Mallard, Mute Swan, Red-breasted Merganser, Ring-necked Duck and Wood Duck. The total number of waterfowl sighted during the survey was 327.

Of the 327 birds sighted, their activities were broken down as such:

Activity 2015 2014 2013
Feeding 67 (21%) 103 (38%) 53 (36%)
Resting 242 (74%) 162 (60%) 88 (60%)
Traveling 18 (5%) 7     (1%) 5   (3%)

Frequency

The species are listed in the table below based on the frequency with which they were seen on the 36 counts:

Species 2015 2014 2013 2015 Notes
Canada Goose 11 7 8 Between 2 and 36; appeared in October onward
Mute Swan 9 16 7
Bufflehead 8 6 1
Mallard 8 7 1
Ring-necked Duck 4 4 3
Hooded Merganser 2 6 2
Red-breasted Merganser 1 0 0 Flew over, never set on the pond
Wood Duck 1 0 0 Spooked from behind island
American Black Duck 0 1 0
Common Loon 0 1 0
Pied-billed Grebe 0 1 0
Ruddy Duck 0 1 1

Abundance

Over the course of the eighteen weeks, the eight species were sighted in the total numbers listed below:

Species 2015 2014 2013 2015 Notes
Canada Goose 228 84 83 Often moved into nearby fields
Mallard 42 15 3
Bufflehead 17 9 1
Mute Swan 17 64 28 Presumably 2 individuals
Hooded Merganser 13 22 6
Red-breasted Merganser 5 0 0
Ring-necked Duck 4 74 24
Wood Duck 3 0 0
American Black Duck 0 10 0
Common Loon 0 1 0
Pied-billed Grebe 0 1 0
Ruddy Duck 0 1 1

Conclusions

Three of the ten species listed in 2015 counts breed on or near the pond, and are generally year-round residents, as long as the pond remains open: Mute Swan, Canada Goose and Mallard. Wood Ducks and Hooded Mergansers nest in Massachusetts, but do not frequent Jacobs Pond. In 2015, the first migrant, a Ring-necked Duck, appeared on October 9. The last recorded migrants were two Buffleheads on December 21. All of the species listed in 2015 overwinter in Massachusetts.

The findings in this report were consistent with several other area surveys. Ring-necked Ducks were down, and Wood Ducks were up during the South Shore Bird Club’s annual Plymouth County waterfowl count in November, meaning that temperatures hadn’t dropped to cold enough levels to really start migration by that point. On December 27, 2015, only 5 Ring-necked Ducks were counted on the Marshfield Christmas Bird Count (encompassing Marshfield, Pembroke, Duxbury and part of Kingston), as temperatures had reached nearly 70 degrees on Christmas Eve. Ponds to the north were still unfrozen, so little movement had seemingly taken place. Most of the birds seen on this survey were year-round residents, with only a handful of migrants passing through.

This survey is paired with a spring survey that begins when the pond thaws. Since the pond thawed so late in 2015, on April 13, the survey basically caught one week of northward migration. Here’s to more ducks in 2016!