The 105th Hamilton Christmas Bird Count was held on December 26, 2025. This is a preliminary report where some details will be missing or a bit more generalized. A later final report will fill in these details in full. The count circle centres upon Dundurn Castle; it is bounded in the west by Christie Lake, in the east by Lake Ontario, in the north by Lake Medad, and in the south by Hamilton International Airport. It includes two Key Biodiversity Areas (KBAs): the West End of Lake Ontario (WELO) KBA, and Hamilton Harbour Waterbird Colonies KBA. The day’s weather was challenging for birding, starting off with overcast, -6° C and ENE winds of 30 km/h, leading to later snow, sleet, then freezing rain and a high of -2° C. Most field counters called it a day by about 1:30 pm in the afternoon due to this weather. Some locations important to the count, such as the RBG’s Arboretum, were closed completely and inaccessible. At least 53 separate parties of counters were active on the count day. With almost all reports in by the time of writing, 95 species were counted on the day. Add to this an additional 7 species from the count week period brings the total in at 102 species for the count period. (Remaining reports may affect this, and add to further data below.) A total of 28,901 individual birds were counted, making for a substantially below-average count, 8,151 less than the ten-year average of 37,052. Despite the challenging circumstances, five species managed to have record-high counts this year. Trumpeter Swan came in strong with 211 individuals counted in 9 different locations. This beats the previous record of 193 in 2010. While most waterfowl had below-average counts this year, a total of 1,843 Red-breasted Mergansers were found, setting a record two years in a row (1,301 last year). The vast majority of these (1,711) were in a single location, Windermere Basin. The Yellow-bellied Sapsucker has now been present for five years in a row, the longest streak it has ever maintained in the history of the count. With 5 individuals counted by 4 separate count groups this year, it has set a new record. Once again we have counted 7 Merlins on count day, and this is the third time this exact record has been matched (2015, 2021, 2025). The species has been seen every year since 1998, and in the last 25 years the average has been 4 found per count. This species was seen by six different groups. The most impressive record of the year is the discovery of 12 Hermit Thrush, seen by 7 different groups, beating out a record of 11 seen in 2002 and being only the second count on record to have double-digit counts of this species. As expected in a count with a low total, some species hit record lows not seen in the count since the very early days of the count where only a few participants were involved. While our count circle began in 1921, it wasn’t until 1955 that it was standardized for scientific purposes with a set circle. Since that time, we have never had as few House Sparrows as this year, with a count of 841. Song Sparrow also hit a record low, with only 9 observed, the first single-digit report in the 70 counts since 1955. Species with a 25-year low included: Bufflehead (103), Mourning Dove (189), Ring-billed Gull (298), Downy Woodpecker (111), Black-capped Chickadee (584), White-breasted Nuthatch (115), Northern Mockingbird (4), House Finch (99), and Northern Cardinal (319). Count week species included: Glaucous Gull, Lesser Black-backed Gull, Snowy Owl, Great Horned Owl, Fox Sparrow, Common Grackle, Yellow-rumped Warbler. A lot of these lows are likely due to the very poor weather making observation conditions challenging. (A later final report will be able to comment on whether hours-effort was affected by weather conditions.) Thank you to the dozens of participants this year, especially given our poor weather conditions! We consistently see between 90 to 110 participants each year making this one of the biggest counts in the province and it is evident from the results that our counters are very determined to find all they can. If you have any questions about this report or the Hamilton count, please feel free to reach out to me.  For exact numbers of each species, see the raw data below this written section. Happy New Year, Rob Porter Hamilton Christmas Bird Count Compiler Hamilton Naturalists’ Club Additional Notes: Last year’s report can be seen at: https://ebird.org/tripreport/311739 CBC Hamilton wrote an article about our count (using early preliminary data): https://www.cbc.ca/news/canada/hamilton/hamilton-bird-count-2025-9.7029182 Species Count Data Count Day Species: 95 Count Week Species: 7 Total Species Countable: 102 Spuh/Slash Species: 4 Hybrid Species: 0 * Record high (105 years) *10y 10-year high CW denotes "Count Week" species (3 days before or after the count day but not observed the day-of) Cackling Goose   3  Canada Goose   6,584  Mute Swan   44  *Trumpeter Swan   211  Tundra Swan   9  Wood Duck   2  Northern Shoveler   66  Gadwall   49  American Wigeon   1  Mallard   5,019  American Black Duck   204  Northern Pintail   6  Green-winged Teal   6  Canvasback   45  Redhead   26  Ring-necked Duck   85  Greater Scaup   732  Lesser Scaup   36  Surf Scoter   5  White-winged Scoter   117  Black Scoter   4  Long-tailed Duck   548  Bufflehead   103  Common Goldeneye   833  Hooded Merganser   87  Common Merganser   1,438  *Red-breasted Merganser   1,843  Ruddy Duck   55  duck sp.   14  Wild Turkey   106  Rock Pigeon   1,471  Mourning Dove   189  American Coot   44  Ring-billed Gull   298  American Herring Gull   331  Great Black-backed Gull   11  Glaucous Gull CW  Lesser Black-backed Gull CW  Iceland Gull   1  gull sp.   15  Pied-billed Grebe   1  Horned Grebe   2  Common Loon   2  Double-crested Cormorant   54  Black-crowned Night Heron   1  Great Blue Heron   3  Turkey Vulture   9  Sharp-shinned Hawk   2  Cooper's Hawk   14  Northern Harrier   1  Bald Eagle   13  Red-shouldered Hawk   1  Red-tailed Hawk   66  Rough-legged Hawk   1  hawk sp.   1  *10y Eastern Screech-Owl   10  Snowy Owl CW  Great Horned Owl CW  Belted Kingfisher   2  *Yellow-bellied Sapsucker   5  Red-bellied Woodpecker   83  Downy Woodpecker   111  Hairy Woodpecker   45  Pileated Woodpecker   2  Northern Flicker   10  American Kestrel   1  *Merlin   7  Peregrine Falcon   3  Northern Shrike   1  Blue Jay   235  American Crow   331  Common Raven   16  Black-capped Chickadee   584  Tufted Titmouse   1  Golden-crowned Kinglet   9  White-breasted Nuthatch   115  Red-breasted Nuthatch   40  Brown Creeper   19  Winter Wren   2  Carolina Wren   30  European Starling   2,433  Gray Catbird   1  Northern Mockingbird   4  Eastern Bluebird   30  *Hermit Thrush   12  American Robin   671  Cedar Waxwing   169  House Sparrow   841  House Finch   99  Purple Finch   2  Pine Siskin   46  American Goldfinch   526  finch sp.   10  American Tree Sparrow   160  Fox Sparrow CW  Dark-eyed Junco   968  White-crowned Sparrow   16  White-throated Sparrow   104  Song Sparrow   9  Swamp Sparrow   1  Red-winged Blackbird   4  Brown-headed Cowbird   1  Common Grackle CW  Orange-crowned Warbler   1  Yellow-rumped Warbler CW  Northern Cardinal   319  TOTAL 28,901 Rob Porter Director of Bird Studies, Hamilton Naturalists' Club Creator/Host, "Songbirding" Podcast rob@songbirding.com