100th Hamilton CBC Report

RP
Rob Porter
Tue, Jan 12, 2021 2:05 AM

The 100th Hamilton Christmas Bird Count (CBC) was held on Saturday,
December 26 in Hamilton, Ontario.

The Hamilton CBC 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 Important Bird & Biodiversity Areas (IBAs): West End of Lake Ontario
(WELO) IBA, and Dundas Valley & Dundas Marsh IBA.

The weather on count day was mostly overcast with some light snow. The
thermometer was ranging between -7°C and -4°C, and there were WSW winds
between 25 and 35 km/h.

A record-setting one hundred and eleven participants either set out to
count in the field or watch birdfeeders, with many out alone alone and the
rest working in much smaller parties than is normal in typical counts. With
an ongoing pandemic no group meetups were arranged and counters were much
more widely distributed. As a consequence far more urban zones were covered
than usual.

A total of 282 hours effort was put in by the participants, with a
resulting 105 different species observed, plus another 2 on the count week,
giving a result of 107 species countable. The day count of species is a new
record, beating the previous 2011 record of 104.

A total of 37,327 individual birds were counted on the count day. This is
8,630 below the 10-year average and 23,937 below the 25-year average. It is
only 159 more than last year, a notably poor year for total birds counted.

The lower count numbers can be partly explained by the lack of cover ice
over the waterways. In years where ice is prevalent there tends to be much
higher concentrations of waterfowl in our count circle.

Two other "low" records set this year were the American Kestrel with only
one lone individual observed, and the Golden-crowned Kinglet with only 4
counted.

The first significant year for winter finches in a long time helped
contribute to the record number of species counted on count day, albeit in
small numbers. Surprisingly, I cannot find any other year like this one
where both grosbeak and both crossbill species appeared in a single count,
even with count week taken into account.

This year we added one new species and a new hybrid to the list. A pair of
Ross's Geese were present in Bayfront park, these were birds known to be
residing there since December. Additionally, a Ring-necked Duck x Redhead
hybrid was observed in Hamilton Harbour.

Six species records were set or matched, four of which were species that
required compiler adjustments based on field notes of counters due to these
species soaring over multiple zones throughout the day.

Hooded Merganser was a surprise new record, with 288 counted, 96 over the
previous record only four years ago.

Pacific Loon was a matched record, with a lone individual counted.

Turkey Vulture set a new record with an adjusted tally of 11. While 22 were
reported, half of those could be eliminated using the clear field notes
given by counters. This is a tough species to reduce as a compiler as
individuals do not generally have distinguishing features; with the
wintering population of Turkey Vultures increasing quickly and its tendency
to wander in plain sight over the heads of multiple counters in a day, this
species may become difficult to count accurately.

Bald Eagle also set a new record, with an adjusted final count of 16. Even
with good field notes this one was a difficult species to adjust, from an
original tally of 24 observations.

Peregrine Falcon tied the 2005 record of 6 counted, after an adjustment
down from 9 observations.

Finally, the Common Raven has been breaking records year after year, this
year doubling the record with 12 counted. This species' count was reduced
down from a staggering 26 counted in the field. A single flock of 7
observed by two parties is the source of more ravens than have ever been
seen in any Hamilton Christmas Bird Count. Along with vultures, these will
be difficult to accurately count if populations continue to grow.

There is one other notable record set: this year a total of 93 eBird
checklists were submitted by counters. This unfortunately coincided with
the year that eBird decided to remove tools useful for compilers, making
the first year where management of data via eBird was actually more
difficult than by spreadsheet, and led to significant delays in compiling
the data. Hopefully these tools return soon to make IBA Surveys and CBCs
manageable via eBird again. Thank you to Kent Fiala for his online eBird
checklist compiler application which made this process at least somewhat
manageable.

This year we were unable to do much special for the 100th count. We hope
that perhaps next year, on the 100th anniversary of the first count held in
1921, we can then celebrate the occasion in person.

For any who may have interest in helping in future counts, please contact
me. With the growth of the count it is time for this event to be managed
with a committee. I plan to continue being compiler for the foreseeable
future but the intake of counter forms and assignment of zones and
promotion of the count are jobs that are better done with a team of more
than one.

Please see the full details of the count below -- it is worth noting that a
number of 10-year record highs were also set this year.

Thank you to everyone who participated in this year's momentous count. Even
if many of you felt the numbers of species or birds overall felt low in
your specific patch, with the efforts of everyone combined we have shown
there are still plenty of positive records to be set in the next hundred
counts.

Rob Porter,
Compiler, 100th Hamilton Christmas Bird Count

=====

The Hamilton Christmas Bird Count is one of many efforts by the Hamilton
Naturalists' Club (HNC) to promote the enjoyment of nature in the Hamilton
area. If you were a counter or are just interested in birds and nature in
Hamilton, please consider becoming a member of the club. For more
information, visit
https://hamiltonnature.org/ -- during the pandemic we are still hosting
monthly meetings (online) with presentations about a variety of subjects
involving the natural world.

You can also join in conversations about nature in Hamilton on the HNC's
Discord chat server. You may join by following this invite link:
https://discord.gg/WmDhsKY

Kent Fiala's "eBird Checklist Compiler" which I used can be found at:
https://www.faintlake.com/eBird/compiler/

=====

The raw data:

  • = New highest record in count history (100 counts)
    *10y = Highest count in last 10 years
    *25y = Highest count in last 25 years
    CW = Count Week species

  • Participants 111
    Hours Effort 281.65

  • Day Species Count 105
    Spuhs & Slashes 8
    Hybrids 3
    Count Week Species 2
    Total Species Countable 107

Species counts:

Numbers in parenthesis are unadjusted counts submitted, reduced by the
compiler based on reasonable assumption of double-counting of one or more
individual birds.

  • Ross's Goose 2
    Canada Goose 6776
    Mute Swan 56
    Trumpeter Swan 83
    Tundra Swan 11
    Northern Shoveler 115
    *10y Gadwall 141
    American Wigeon 2
    Mallard 2808
    American Black Duck 148
    Mallard x American Black Duck (hybrid) 4
    Northern Pintail 1
    Green-winged Teal 1
    Canvasback 200
    Redhead 78
  • Canvasback x Redhead (hybrid) 1
  • Ring-necked Duck x Redhead 1
    Ring-necked Duck 46
    Greater Scaup 56
    Lesser Scaup 30
    Surf Scoter 13
    White-winged Scoter 611
    Black Scoter 9
    Long-tailed Duck 7523
    Bufflehead 423
    Common Goldeneye 1131
  • Hooded Merganser 288
    Common Merganser 486
    Red-breasted Merganser 90
    Ruddy Duck 84
    duck sp. 8
    Wild Turkey 112
    Pied-billed Grebe 1
    Horned Grebe 4
    Red-necked Grebe 1
    Rock Pigeon 1526
    Mourning Dove 692
    American Coot 70
    Ring-billed Gull 739
    Herring Gull 849
    Iceland Gull 4
    Lesser Black-backed Gull 2
    Glaucous Gull 4
    Great Black-backed Gull 89
    gull sp. 125
    Red-throated Loon 1
  • Pacific Loon 1
    Common Loon 1
    Double-crested Cormorant 59
    Great Blue Heron 3
  • Turkey Vulture 11 (22)
    Northern Harrier 2
    Sharp-shinned Hawk 5
    Cooper's Hawk 20
    accipiter sp. 1
  • Bald Eagle 16 (24)
    Red-tailed Hawk 99
    Rough-legged Hawk 5
    eagle sp. 1
    Eastern Screech-Owl 7
    Great Horned Owl 6
    Snowy Owl 1
    Belted Kingfisher 3
    Red-bellied Woodpecker 107
    Downy Woodpecker 241
    Hairy Woodpecker 82
    Downy/Hairy Woodpecker 1
    Pileated Woodpecker 7
    Northern Flicker 3
    woodpecker sp. 2
    American Kestrel 1
    Merlin 6
  • Peregrine Falcon 6 (9)
    Northern Shrike 1
    Blue Jay 287
    *10y American Crow 778
  • Common Raven 12 (26)
    *10y Horned Lark 47
    Black-capped Chickadee 998
    Tufted Titmouse 1
    *10y Red-breasted Nuthatch 85
    White-breasted Nuthatch 215
    Brown Creeper 18
    Winter Wren 15
    Carolina Wren 99
    Golden-crowned Kinglet 4
    Eastern Bluebird 49
    Hermit Thrush 4
    American Robin 347
    Gray Catbird 2
    Northern Mockingbird 12
    European Starling 2505
    Cedar Waxwing 203
    Evening Grosbeak 4
    *10y Pine Grosbeak 12
    House Finch 380
    Common Redpoll 47
    *10y Red Crossbill 1
    *10y White-winged Crossbill 30
    Pine Siskin 78
    American Goldfinch 701
    finch sp. 1
    Snow Bunting 236
    Chipping Sparrow 1
    American Tree Sparrow 434
    Dark-eyed Junco 971
    *10y White-crowned Sparrow 22
    *10y White-throated Sparrow 122
    Song Sparrow 36
    Swamp Sparrow 1
    Eastern Towhee 1
    sparrow sp. 4
    Red-winged Blackbird 2
    Brown-headed Cowbird CW
    Orange-crowned Warbler CW
    Yellow-rumped Warbler 1
    *10y Northern Cardinal 633
    House Sparrow 1785

TOTAL BIRDS COUNTED 37,327

--
Robert Gerald Porter

Hamilton Naturalists' Club / Director at Large
Weever Apps / Director of Engineering, Co-founder
Songbirding Podcast / Creator, Host

http://twitter.com/rgeraldporter

The 100th Hamilton Christmas Bird Count (CBC) was held on Saturday, December 26 in Hamilton, Ontario. The Hamilton CBC 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 Important Bird & Biodiversity Areas (IBAs): West End of Lake Ontario (WELO) IBA, and Dundas Valley & Dundas Marsh IBA. The weather on count day was mostly overcast with some light snow. The thermometer was ranging between -7°C and -4°C, and there were WSW winds between 25 and 35 km/h. A record-setting one hundred and eleven participants either set out to count in the field or watch birdfeeders, with many out alone alone and the rest working in much smaller parties than is normal in typical counts. With an ongoing pandemic no group meetups were arranged and counters were much more widely distributed. As a consequence far more urban zones were covered than usual. A total of 282 hours effort was put in by the participants, with a resulting 105 different species observed, plus another 2 on the count week, giving a result of 107 species countable. The day count of species is a new record, beating the previous 2011 record of 104. A total of 37,327 individual birds were counted on the count day. This is 8,630 below the 10-year average and 23,937 below the 25-year average. It is only 159 more than last year, a notably poor year for total birds counted. The lower count numbers can be partly explained by the lack of cover ice over the waterways. In years where ice is prevalent there tends to be much higher concentrations of waterfowl in our count circle. Two other "low" records set this year were the American Kestrel with only one lone individual observed, and the Golden-crowned Kinglet with only 4 counted. The first significant year for winter finches in a long time helped contribute to the record number of species counted on count day, albeit in small numbers. Surprisingly, I cannot find any other year like this one where both grosbeak and both crossbill species appeared in a single count, even with count week taken into account. This year we added one new species and a new hybrid to the list. A pair of Ross's Geese were present in Bayfront park, these were birds known to be residing there since December. Additionally, a Ring-necked Duck x Redhead hybrid was observed in Hamilton Harbour. Six species records were set or matched, four of which were species that required compiler adjustments based on field notes of counters due to these species soaring over multiple zones throughout the day. Hooded Merganser was a surprise new record, with 288 counted, 96 over the previous record only four years ago. Pacific Loon was a matched record, with a lone individual counted. Turkey Vulture set a new record with an adjusted tally of 11. While 22 were reported, half of those could be eliminated using the clear field notes given by counters. This is a tough species to reduce as a compiler as individuals do not generally have distinguishing features; with the wintering population of Turkey Vultures increasing quickly and its tendency to wander in plain sight over the heads of multiple counters in a day, this species may become difficult to count accurately. Bald Eagle also set a new record, with an adjusted final count of 16. Even with good field notes this one was a difficult species to adjust, from an original tally of 24 observations. Peregrine Falcon tied the 2005 record of 6 counted, after an adjustment down from 9 observations. Finally, the Common Raven has been breaking records year after year, this year doubling the record with 12 counted. This species' count was reduced down from a staggering 26 counted in the field. A single flock of 7 observed by two parties is the source of more ravens than have ever been seen in any Hamilton Christmas Bird Count. Along with vultures, these will be difficult to accurately count if populations continue to grow. There is one other notable record set: this year a total of 93 eBird checklists were submitted by counters. This unfortunately coincided with the year that eBird decided to remove tools useful for compilers, making the first year where management of data via eBird was actually more difficult than by spreadsheet, and led to significant delays in compiling the data. Hopefully these tools return soon to make IBA Surveys and CBCs manageable via eBird again. Thank you to Kent Fiala for his online eBird checklist compiler application which made this process at least somewhat manageable. This year we were unable to do much special for the 100th count. We hope that perhaps next year, on the 100th anniversary of the first count held in 1921, we can then celebrate the occasion in person. For any who may have interest in helping in future counts, please contact me. With the growth of the count it is time for this event to be managed with a committee. I plan to continue being compiler for the foreseeable future but the intake of counter forms and assignment of zones and promotion of the count are jobs that are better done with a team of more than one. Please see the full details of the count below -- it is worth noting that a number of 10-year record highs were also set this year. Thank you to everyone who participated in this year's momentous count. Even if many of you felt the numbers of species or birds overall felt low in your specific patch, with the efforts of everyone combined we have shown there are still plenty of positive records to be set in the next hundred counts. Rob Porter, Compiler, 100th Hamilton Christmas Bird Count ===== The Hamilton Christmas Bird Count is one of many efforts by the Hamilton Naturalists' Club (HNC) to promote the enjoyment of nature in the Hamilton area. If you were a counter or are just interested in birds and nature in Hamilton, please consider becoming a member of the club. For more information, visit https://hamiltonnature.org/ -- during the pandemic we are still hosting monthly meetings (online) with presentations about a variety of subjects involving the natural world. You can also join in conversations about nature in Hamilton on the HNC's Discord chat server. You may join by following this invite link: https://discord.gg/WmDhsKY Kent Fiala's "eBird Checklist Compiler" which I used can be found at: https://www.faintlake.com/eBird/compiler/ ===== The raw data: * = New highest record in count history (100 counts) *10y = Highest count in last 10 years *25y = Highest count in last 25 years CW = Count Week species * Participants 111 Hours Effort 281.65 * Day Species Count 105 Spuhs & Slashes 8 Hybrids 3 Count Week Species 2 Total Species Countable 107 Species counts: Numbers in parenthesis are unadjusted counts submitted, reduced by the compiler based on reasonable assumption of double-counting of one or more individual birds. * Ross's Goose 2 Canada Goose 6776 Mute Swan 56 Trumpeter Swan 83 Tundra Swan 11 Northern Shoveler 115 *10y Gadwall 141 American Wigeon 2 Mallard 2808 American Black Duck 148 Mallard x American Black Duck (hybrid) 4 Northern Pintail 1 Green-winged Teal 1 Canvasback 200 Redhead 78 * Canvasback x Redhead (hybrid) 1 * Ring-necked Duck x Redhead 1 Ring-necked Duck 46 Greater Scaup 56 Lesser Scaup 30 Surf Scoter 13 White-winged Scoter 611 Black Scoter 9 Long-tailed Duck 7523 Bufflehead 423 Common Goldeneye 1131 * Hooded Merganser 288 Common Merganser 486 Red-breasted Merganser 90 Ruddy Duck 84 duck sp. 8 Wild Turkey 112 Pied-billed Grebe 1 Horned Grebe 4 Red-necked Grebe 1 Rock Pigeon 1526 Mourning Dove 692 American Coot 70 Ring-billed Gull 739 Herring Gull 849 Iceland Gull 4 Lesser Black-backed Gull 2 Glaucous Gull 4 Great Black-backed Gull 89 gull sp. 125 Red-throated Loon 1 * Pacific Loon 1 Common Loon 1 Double-crested Cormorant 59 Great Blue Heron 3 * Turkey Vulture 11 (22) Northern Harrier 2 Sharp-shinned Hawk 5 Cooper's Hawk 20 accipiter sp. 1 * Bald Eagle 16 (24) Red-tailed Hawk 99 Rough-legged Hawk 5 eagle sp. 1 Eastern Screech-Owl 7 Great Horned Owl 6 Snowy Owl 1 Belted Kingfisher 3 Red-bellied Woodpecker 107 Downy Woodpecker 241 Hairy Woodpecker 82 Downy/Hairy Woodpecker 1 Pileated Woodpecker 7 Northern Flicker 3 woodpecker sp. 2 American Kestrel 1 Merlin 6 * Peregrine Falcon 6 (9) Northern Shrike 1 Blue Jay 287 *10y American Crow 778 * Common Raven 12 (26) *10y Horned Lark 47 Black-capped Chickadee 998 Tufted Titmouse 1 *10y Red-breasted Nuthatch 85 White-breasted Nuthatch 215 Brown Creeper 18 Winter Wren 15 Carolina Wren 99 Golden-crowned Kinglet 4 Eastern Bluebird 49 Hermit Thrush 4 American Robin 347 Gray Catbird 2 Northern Mockingbird 12 European Starling 2505 Cedar Waxwing 203 Evening Grosbeak 4 *10y Pine Grosbeak 12 House Finch 380 Common Redpoll 47 *10y Red Crossbill 1 *10y White-winged Crossbill 30 Pine Siskin 78 American Goldfinch 701 finch sp. 1 Snow Bunting 236 Chipping Sparrow 1 American Tree Sparrow 434 Dark-eyed Junco 971 *10y White-crowned Sparrow 22 *10y White-throated Sparrow 122 Song Sparrow 36 Swamp Sparrow 1 Eastern Towhee 1 sparrow sp. 4 Red-winged Blackbird 2 Brown-headed Cowbird CW Orange-crowned Warbler CW Yellow-rumped Warbler 1 *10y Northern Cardinal 633 House Sparrow 1785 TOTAL BIRDS COUNTED 37,327 -- Robert Gerald Porter Hamilton Naturalists' Club / Director at Large Weever Apps / Director of Engineering, Co-founder Songbirding Podcast / Creator, Host http://twitter.com/rgeraldporter