Niagara Peninsula Hawkwatch

 
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2011 MIGRATION SUMMARY

By John Stevens

Hawk-watchers at Beamer Memorial Conservation Area (Beamer) had reason to be ecstatic in 2011 as a record number of 20,368 raptors were counted, exceeding the previous high of 19,275 set in 1985. Yet, I suspect many felt little ecstasy as day after day of cool, wet weather persisted through April and May. In many respects this was a very abnormal season with low numbers of most species being recorded and the total count dominated by record counts of Turkey Vultures and Broad-winged Hawks, the two most commonly seen species.

We passed a milestone just after noon on April 27th when the 500,000th raptor was counted since we began in 1975. It went unnoticed as the birds were coming through so furiously at the time that the actual individual was not identified but it would be nice to think that it was one of the Golden Eagles that were seen early in the hour.

The Weather

If we hadn’t had a record number of birds, the main story for 2011 would have been the weather. 39 of the 76 days between March 1 and May 15 had one or more of snow, rain, fog, hail, even sleet during the counting hours and April 28th, while precipitation-free, was so windy that trees were falling throughout the woods including three of our directional markers. Several of the counters had to wait out many hours of inclement weather just to get in a few licks of raptor movement. There were eight days when it rained or snowed all day and no count was conducted that are included in the 13 days with no raptors recorded. One day was inadvertently not covered in May.

The temperature remained cool pretty well through to the end of the count period. We had the occasional warm day and these tended to produce good flights making for a very concentrated movement. The exception was late March when a string of steady flights of Turkey Vultures occurred. The first Broad-winged Hawks (212) appeared more or less on time on April 12th but the following nine days produced only 66 more before an excellent flight occurred on April 22nd.

Unlike the last two years, we had our share of snow in March including an all day storm on March 23rd and then a five hour snowfall on the late date of April 18th. While the average temperature for the month of 0.2ºC was right on normal, the maximum was only 16ºC. Temperatures in April on average were slightly above normal and also in May although during the first half of the month when we were counting, they were slightly below. However, the most startling data indicate that total precipitation for the March-May period was 454 mm compared to the normal amount of 215 mm (i.e., more than double the norm).

The Flight

The seasonal weather in early March meant there was the typical slow start to the season. On March 1st, the first bird of the year was a Peregrine Falcon, moving southeast, and the second bird was a dark morph Rough-legged Hawk. This was quite a rewarding start for the gang installing the windbreak and signboard. With five zeros in the first two weeks though, a count of 111 on March 14 exceeded the year’s total to that date and the next day’s 311 did that again. Thereafter the March flight was very good, in fact the highest total, 6,389, in the 37 years of recorded data. The best date was the warmest day of the month, March 18, when almost 900 Turkey Vultures pushed the total to 1,091.

Early in April there were two reasonable TV flight days but by the half way point in the season on April 7th, we’d had only one Osprey, no Golden Eagles or Northern Goshawks, and the Broad-winged Hawks had yet to make an appearance. Despite continuing coolness and periodic rain, the next five days produced a good number of Ospreys, Northern Harriers and Sharpies, the first Goshawk and on the 12th, the first Broad-winged Hawks (212). However, only 66 Broad-wings were seen during the following nine days of cool, wet and windy weather coming into Good Friday and the annual Open House on the 22nd. Fortunately the forecasted rain held off until after 3 pm and the Broad-wings flooded through at low altitude along with 12 other species producing a count of 2,025 birds for the assembled masses. Having attended all but one of our Open Houses, this was the greatest total in my memory but I’ve not checked the records.

The best, though, was yet to come. There followed five days with varying periods of rain, winds and fog that included another great flight of 1,947 birds on April 24th but concluded with a total washout on April 26th. On April 27th, a warm front lay along the southern Lake Ontario shoreline that had cool foggy conditions to the north and clearing, much warmer air to the south. A strengthening easterly wind brought a great flight of birds over Beamer that consisted of 14 of our 15 regular species (no Goshawk) and was highlighted by 4,464 Broad-wings, almost all at reasonable elevations. The final count of 5,291 birds (Table 2) represents the second greatest daily count in the history of our watch, beaten only by April 21, 1985. Only the approach of a cold front and the associated rain that shut down the flight in the middle of the afternoon prevented a new record daily total but we had established a new seasonal record by passing the 19,275 birds recorded in 1985. The April total of 13,667 birds was the third highest on record.

That was pretty much it for the season. Counts continued for three more weeks but no other significant flight days were recorded. On the last day of April we cracked 20,000 birds in a season for the first time. The weather in the first half of May was miserable and noday produced more than 60 raptors (Table 3) leading to a count of only 318 for the month, the second lowest total since 1976, before complete coverage was begun. The number of hours covered in May was the lowest since complete seasonal coverage began in 1981 contributing to the annual total of hours being tied with 2005 as the second lowest ever.

Species Highlights

Turkey Vultures continued to increase in number, passing the record set last year and finishing at 7,125 (Table 4). It is becoming increasingly difficult to monitor the migrants in the latter part of the season with the number of local birds residing in Niagara, particularly those that cruise back and forth along the escarpment.

As indicated earlier, the Broad-winged Hawk total of 8,613 broke our previous high count of 8,239 that was set in 1985. I suspect that this happened because of the inclement weather experienced during April. Broad-winged Hawks can get very high in the warmer weather of late April and May such that they are pretty well out of sight to us unless we happen to have a glide path overhead. This year, we had many Broad-wings at relatively low elevations, particularly on the big days of April 22, April 24 and April 27.

The only other species that exceeded their five-year or long-term averages were Merlins and Peregrine Falcons. The Merlin total may be unrealistic as there were a number of sightings of a roosting Merlin in the vicinity of the watch site this year suggesting that a bird or birds was resident for a while and may have been counted more than once. The Peregrine count was second highest to last year’s total of 12.

The news is pretty grim on the remaining 11 species regularly seen at Beamer. All were seen in numbers below their recent 5-year average and all except Bald Eagles were seen at numbers below their long-term average. A record low count of Red-tailed Hawks representing just 64% of the long-term average was set this year. The Sharp-shinned Hawk total of 1,700 was the second lowest on record (1,551 in 2007) and continues the trend that has seen the recent five-year average fall to barely more than one half of the long-term average. The count of Cooper’s Hawks at 101 was at an all-time low and less than half what it was five years ago. The American Kestrel count was one below the previous low count set in 2005 and represented just 44% of the long-term average. The Northern Goshawk count of just 2 was also a record low but probably not that significant in this a non-irruptive year. The Northern Harrier total of 104 was the fifth lowest for the site.

Somewhat more encouraging findings can be reported for Red-shouldered Hawks, whose number increased from last year though remaining well below their long-term average, and Rough-legged Hawks, whose total rebounded to 59 from last year’s low count of 29.

In all four species were recorded in record low numbers as compared to the two species setting new record high counts. It is to be hoped that the birds of the 11 species with low seasonal numbers were able to navigate northward avoiding the poor weather conditions at Beamer and do not indicate a marked decline in their populations.

Again this year a Black Vulture was seen at Beamer and a second bird of this species was seen in Grimsby earlier in the year. This marks the third year in the last four when we’ve had at least one of these after only seeing one on three previous occasions during the 37 years of the watch. Black Vultures do not migrate like Turkey Vultures but appear to be undergoing something of a range expansion, moving into more northern territory than their range of the last 150 years.

Acknowledgements

Thanks go to the following volunteers for taking responsibility as designated counters: Bouwe Bergsma, John Black, Barry Cherriere, Bob Curry, Sandy Darling, Keith Dieroff, Chris Escott, Tim Foran, Sandra Horvath, Marcie Jacklin, Gord McNulty, George Naylor, Bill Smith, John Stevens, Mike Street, Tom Thomas, Phil Waggett and Rob Waldhuber. Thanks also to the following people who assisted the designated counters: Cody Law, Colin Horstead, Mike Kirchin, Linda Cherriere, Dave Sked, John Niewiadomski, Dave Weare, Toni Carson, Brian Hawthorn, Doris Southwell, Eric Single, George Holland, Tim King plus many others who appear less frequently but contribute nonetheless.

I would also like to acknowledge the couple who maintain the weather station atop the escarpment near Mountain Road. Their data are very helpful in preparing this report and the on-line availability of the climatological conditions make compiling the HMANA reports so much easier.

Finally, a few comments about selected individuals:

  • to Colin Horstead who missed most of the season because of surgery, continued recovery, we’re looking forward to your return next year;
  • to the dean of hawk watching at Beamer, George Meyers, whom I don’t believe made it out to the site at all this year, we missed you George;
  • to Cody Law, the 14-year old whose sharp young eyes are becoming more discerning each time he appears, we appreciate your dedication, we need more of your ilk; and
  • to Rob Waldhuber, who suffered through two of the more miserable days as designated counter, you’re owed a better day next time.

2011 NIAGARA PENINSULA HAWKWATCH MONTHLY COUNTS

SPECIES
FEB
MAR
APR
MAY
TOTAL
Black Vulture
0
1
0
0
1
Turkey Vulture
0
4,704
2,257
164
7,125
Osprey
0
0
40
1
41
Mississippi Kite
0
0
0
0
0
Bald Eagle
0
30
25
5
60
Northern Harrier
0
16
92
2
104
Sharp-shinned Hawk
0
63
1,580
57
1,700
Cooper's Hawk
0
51
48
3
101
Northern Goshawk
0
0
1
1
2
Red-shouldered Hawk
0
470
108
1
581
Broad-winged Hawk
0
0
8,598
15
8,613
Swainson's Hawk
0
0
0
0
0
Red-tailed Hawk
0
979
828
50
1,857
Ferruginous Hawk
0
0
0
0
0
Rough-legged Hawk
0
35
20
3
59
Golden Eagle
0
0
7
1
8
American Kestrel
0
9
29
6
44
Merlin
0
2
11
4
17
Peregrine Falcon
0
4
6
1
11
Gyrfalcon
0
0
0
0
0
Prairie Falcon
0
0
0
0
0
Unidentified Accipiter
0
1
1
1
3
Unidentified Buteo
0
21
9
0
30
Unidentified Eagle
0
0
0
0
0
Unidentified Falcon
0
0
2
0
2
Unidentified Raptor
0
2
4
3
9
Total Raptors
0
6,388
13,666
318
20,368
Hour Counted
0
209.5
210.7
75
495.2
Raptors/Hour
0
30.5
64.9
4.2
41.1
 
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