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Total Counts Run, Total Species Found, and Number of Participants

Christmas Bird Counts (CBCs) were completed on 31 of Montana’s 36 potential count circles this year (#124), which was similar to the average number of counts completed during the period #115-123 (32).  Several counts are dormant from combinations of a lack of a coordinator, lack of participants, or consistent bad weather during the count period.

We tallied 142 species cumulatively on our various count days (Appendix 1), which was higher than last year (133) but about average for the period #115-123 (141).  Six species were found only during count week (CW, which includes the 3 days before and 3 days after a count day), including Greater White-fronted Goose at Fort Peck, Canvasback at Bigfork and Troy, Long-tailed Duck at Great Falls, Spruce Grouse at Upper Swan Valley, Lapland Longspur at Missoula, and Rusty Blackbird at Ennis.  CW birds do not count toward a circle’s total number of birds tallied, but are recorded because they can be rare or unusual, or helpful in putting records into context.  For example, our first Western Tanager was a CW bird in Hamilton (CBC #116) and eventually was found on a count day in Bozeman (CBC #120). 

We added Great-tailed Grackle (2 birds from Bozeman, photo Appendix 2, and 1 CW bird at Stevensville) to our cumulative Montana list, which still stands at 221 (recall we lost a species with the recent lumping of Thayer’s and Iceland Gull).  It appears that the Great-tailed Grackles have both overwintered in Bozeman and Stevensville this year. 

Missoula had the high count this year at 86 species (and another 4 CW birds).  This was near to their previous high (90 during CBC #121), but well short of the state record at Bigfork (98 from CBC #118).  Bigfork, Missoula, and Stevensville usually have the high count each year (generally in the 80s).  The average number seen this year was 50, which was similar to the average number for the period CBC #115-123 (49).  Four counts tallied 26 or fewer species, due to combinations of fewer field participants and harsh field conditions. 

The total number of participants (857) was higher than last year (770) but similar to the average during the CBC period #115-123 (846).  This year, there were 714 field participants and 143 feeder-watchers; both were fairly similar to their averages during the period #115-123 (field averaged 691, feeder-watchers averaged 155). 

Missoula again had the most participants—91 field participants and 22 feeder-watchers.  Bozeman followed with 62 field participants, and Helena had 53. This year the average number of field participants was 23 while feeder-watchers averaged 6.  Five counts had 6 or fewer participants (and 1 count had just 1). 

This year we tallied 153,378 individual birds (Figure 1), which was about 30% less than the average number of individuals seen over the period #115-123 (218,703 birds).  One reason fewer birds may have been recorded was because of foggy conditions on several count days, Missoula in particular. Lower totals might have also resulted from lower effort, discussed below. 

Total field effort or party hours this year was 1,288.89 (Figure 1).  We track this number because it is the driver of our birds per party hour metric, which we use to compare bird numbers across years. 

This year’s total party hours was about 7% lower than the average total party hours during the period CBC #115-123 (1,386).  In general, less effort (that is, fewer party hours) can result in fewer birds tallied.  That is, if you search less, you will find fewer birds than if you search more. 

Figure 1.  Effort (Total Daytime Field Party Hours, rust) and Number of Individual Birds Recorded (blue), Montana Christmas Bird Counts (CBC) #115-124

Effort somewhat depends on the number of field participants.  However, with an average number of participants this year (691), the total party hours (blue) was the 3^rd lowest of the period CBC #115-124 (Figure 2).

Figure 2.  Effort (party hours, blue), and Number of Field Participants (orange), Montana Christmas Bird Counts #115-124

Perhaps the circles were better covered with more participants, so that less total time in the field was needed to search the area.  That is, perhaps the participants hit all of the highly productive microsites in each count in less time this year.  This might explain fewer total birds being found, yet an essentially average number of species (142 found, average 141) was tallied.  The range of the cumulative number of species found is relatively small, and varies from a high of 147 (during CBC #118, 119), to a low of 133 (during CBC #123).  This might suggest that field counters know which sites to bird in each circle to find the highest diversity of species during each count.

Widespread Species

The Bald Eagle was the most widespread species again this year, found on all 31 counts on count day. 

Figure 3. Bald Eagle Numbers and Birds Per Party Hour, Montana Christmas Bird Counts #48-124, Compared to Preceding Average Birds Per Party Hour

Bald Eagle numbers and birds per party hour were lower than last year, but still above their recent averages (Figure 3).  Bald Eagle populations have recovered from lows in the 60s thanks to conservation efforts and the banning of pesticides during the 70s.                     

Other widespread species were Mallard, Common Raven and Downy Woodpecker—all found on 30 counts.  Canada Goose was found on 29 counts and 1 CW bird (Upper Swan Valley), so 30 counts were represented.  Black-capped Chickadee was found on 29 counts,

Species whose numbers vary widely each year—were they low this year?

Although Mallard birds per party hour can fluctuate greatly, their recent values have been lower than the average birds per party hour since CBC #115 (Figure 4).  This year, Mallard birds per party hour was 42% lower than the average birds per party hour during the period CBC #45-123.  Mallard numbers seem to bounce back above their average birds per party hour every 10 years or so (Figure 4), so the trends do not seem alarming so far.

Figure 4. Mallard Numbers (blue) and Birds Per Party Hour (rust), Montana Christmas Bird Counts #45-124, Compared to Preceding Average Birds Per Party Hour (red).

Canada Goose birds per party hour was also lower than their recent averages, but similar to last year’s values, and well above the average birds per party hour during the period CBC # 51-123 (Appendix 3).  Canada Goose numbers were almost the same as last year’s total (approx. 40,000 birds).

European Starling was also similar to last year’s numbers and birds per party hour, which were about average for the period CBC # 41-123 (Appendix 3).  Starling numbers this year (13,276) were well below the recent high of 24,842 during CBC #116.

After starlings, House Sparrow was the next most numerous species (9,323 birds found on 23 counts and 1 cw bird at Troy).  Numbers and birds per party hour have decreased since CBC #116 (Appendix 3), but not out of the range of variability.

Bohemian Waxwing numbers can fluctuate from the 30,000s to fewer than 100.  Numbers this year (2,211) were substantially lower than last year (9,374).  This year’s birds per party hour for Bohemian Waxwing was close to a record low (Figure 5).  Compared to last year, Cedar Waxwing numbers (715 this year vs 679) and birds per party hour were similar.   

Figure 5.  Bohemian Waxwing Numbers and Birds per Party Hour, Montana Christmas Bird Counts #39-124, Compared to Preceding Average Birds per Party Hour

Pine Grosbeak

During late fall 2023, many observers had found Pine Grosbeaks consistently and in fairly large numbers throughout western Montana.  A winter irruption was predicted in suitable habitats (such as riparian areas) and feeders by the Finch Research Network (https://finchnetwork.org/western-irruption-alert-pine-grosbeaks-cassins-finches-and-others-making-record-movements).  I was curious if this would show up during the Montana CBC.  Pine Grosbeak was found on 18 counts and 2 CW sites, so 20 of 31 counts were represented.  We tallied 519 birds; count totals ranged from 122 at Kalispell to 1 at Fort Peck (average 26).  The highest recent previous numbers were 686 during CBC #113 and #116 (Figure 6). 

Figure 6.  Pine Grosbeak Numbers (blue) and Birds Per Party Hour (rust) Montana Christmas Bird Counts #42-124.

The species can winter in the eastern part of the state at lower elevations during some years (Birds of Montana p. 563).  Of interest, Pine Grosbeak was recorded at 3 eastern CBC locations this year—18 at Lewistown, 15 at Musselshell Valley, and 1 at Fort Peck.  Previously, Pine Grosbeak had been recorded once at Musselshell Valley (3 birds in CBC #115) and twice at Fort Peck (3 in CBC #84, and 4 in #120).  It was recorded 5 times previously at Lewistown (47 in CBC #78, 32 in #97, 9 in #113, 16 in #115, and 7 in #119; no counts occurred during #117 and 118).  Similarly, a review of eBird data from Dec 2023 shows the species was unexpectedly recorded (filter was set at 0) in several eastern counties:  Prairie, Fergus, Valley, Musselshell, and Meager; the species exceeded the filter of 6 in Hill County with 8 birds.  January 2024 showed similar trends, and added 28 birds in Gallatin Co. (filter set at 25), 25 birds in Jefferson Co. (filter set at 15), and 63 birds in Lewis and Clark Co. (filter set at 25).

Pine Grosbeak numbers vary widely on Montana CBCs, with corresponding variability in birds per party hour (Figure 6).  Interestingly, this year’s birds per party hour value was the 3^rd highest since CBC #85.  Birds per party hour from the mid-70s and before are perhaps less reliable due to less data review and fewer effort hours recorded during that period, compared to more recent years.  Thus, the magnitude of the birds per party hour peaks would likely be lower now than depicted during that early period of CBC data.

Overall, with a few exceptions, our usual variable or numerous species (e.g., Canada Goose, Mallard, House Sparrow, Bohemian Waxwing)  were either similar to or lower this year, than when compared to recent years. This contributed to our low total individual birds seen this year.  That is, the sum of the parts was low (total individuals), because some of the individual parts were low.  However, none of the decreases appeared out of the range of variability when compared to past counts for these widely-fluctuating species. 

Single sightings

Perhaps because of pre-count scouting or more count-day coverage of some circles, there were several singletons this year—1 count and 1 species recorded (Table 1).  Single sightings likely helped to increase the total number of species recorded this year at Missoula, because several of those species were fairly unusual for that count, but known to be present before count day. 

Table 1.  Single counts with single species recorded count day (and not CW elsewhere), Montana Christmas Bird Count #124

Dove trends

Both Mourning Dove and Eurasian Collared-Doves had lower total numbers and lower birds per party hour than during the past few years (Figure 7).  Mourning Dove numbers are approaching the numbers that occurred during a long period of little fluctuation, from the late 40s through the late 90s.  Recall that Eurasian Collared-Doves were first recorded on our counts on CBC #101.  Oddly, Mourning Dove numbers climbed as Eurasian Collared-Doves climbed during the early 2000s.  Perhaps winter Dove numbers are starting to flatten out after a period of wide fluctuation.

Figure 7.  Mourning Dove Numbers (rust) and Birds per Party hour (gray) Compared to Eurasian Collared-Dove Numbers (blue) and Birds per Party Hour (yellow), Montana Christmas Bird Counts # 48-124

Owls

CBC #124 tallied 8 of 13 potential winter owl species.  Great Horned Owl (GHO) was again relatively widespread, found on 17 counts, and totaling 75 birds.  Stevensville had 18 GHO and Ninepipe had 15; the other counts had 6 or fewer.  We found Eastern Screech-Owl (1 at Miles City), but no Western Screech-Owl.  Also found were Long-eared Owl (9 birds from 3 counts), Short-eared Owl (4 birds from 2 counts plus 1 CW), 1 Barred Owl (Missoula), 1 Great-gray Owl (Libby plus CW in Kalispell and West Yellowstone), Northern Pygmy-Owl (8 birds from 6 counts), and Northern Saw-whet Owl (3 birds from 2 counts plus 1 CW).  We missed Northern Hawk-Owl (found occasionally), Snowy Owl (found fairly regularly), and Barn Owl and Boreal Owl (rarely found).

Gulls

We found 5 gull species—Ring-billed Gull (1,788 from 7 counts), Herring Gull (123 from 4 counts), California Gull (76 birds from 3 counts), Iceland Gull (including former Thayer’s Gull, 1 at Bigfork and CW at Fort Peck), and the now fairly regular Lesser Black-backed Gull (2 birds, 1 each from Bigfork and Fort Peck). 

Other Unusual Records

Other unusual species not already mentioned were Greater White-fronted Goose (CW at Fort Peck, found during 11 previous count years); 3 Ferruginous Hawks-1 each from Ruby Valley and Musselshell Valley, and 1 from Stevensville (unusual from the west side of the state except during winter, but not regular even at that season); 1 Sora at Helena (found on 11 previous counts); 3 Sandhill Cranes from Bozeman (found during 17 previous count years, usually single birds but several records of 2-3); 4 Ruby-crowned Kinglets-1 each from Clark Canyon Dam and Warm Springs, and 2 from Missoula (regular during winter there); and 2 Lewis’s Woodpeckers, 1 each from Missoula and Stevensville.  This usually migrating species has over-wintered at these sites regularly in recent years;

Thanks to all of the participants, and hope to see you again next year.

Appendix 1.  Species tallied during Montana Christmas Bird Count # 124

Appendix 2, photos

Great-tailed Grackle, Andrew Guttenberg photo, 16 Dec 2023, Count Day Bozeman.

Greater Yellowlegs, Jillian Leblow photo, 16 Dec 2023, Count Day Missoula

Appendix 3.  Species with generally high total numbers and near to average birds per party hour, compared to recent past years

Canada Goose Numbers and Birds per Party Hour, Montana Christmas Bird Counts #51-124, compared to preceding Average Birds per Party Hour

European Starling Numbers and Birds per Party Hour Compared to Average Birds per Party Hour, Montana Christmas Bird Counts #41-124

House Sparrow Numbers and Birds per Party Hour Compared to Preceding Average Birds per Party Hour, Montana Christmas Bird Counts #39-124

Literature Cited

J.S. Marks, P. Hendricks, D. Casey.  Birds of Montana. Buteo Books (2016), 659 pp.