Waterfowl breeding population survey for Maine and the Maritimes

              MAINE & THE MARITIMES
Waterfowl Breeding Population Survey
2001
Bangor
Presque Isle
St. John
Fredricton
Sydney
Halifax
Charlottetown
St. Johns
St. Anthony
Goose Bay
Wabush
62
63
64
66
67
65
TITLE: Waterfowl Breeding Population Survey for Maine and the Maritimes
STRATA SURVEYED: 62, 63, 64, 65, 66 and 67
DATES: May 2 through June 2, 2001
DATA SUPPLIED BY: United States Fish and Wildlife Service (USFWS)
Canadian Wildlife Service (CWS)
Aerial Crew:
Pilot/Observer: John Bidwell, Flyway Biologist, USFWS
Observer: Marty Drut, Wildlife Biologist, USFWS
ABSTRACT
The 2001 waterfowl breeding population survey of Maine and the Maritimes was
conducted from May 2 through June 2. All transects and segments were flown and comparisons
made with the historical data set, which includes estimates from 1996 through 2000. This was
the second operational year for the survey.
Cooler temperatures and abundant snowfall describes the winter of 2000-01. Also, a late
spring delayed migration and may help explain the (-12.2%) decline in total ducks from 2000.
Survey estimates for selected species, total ducks and NAP Canada geese, are listed below.
Species 2001 estimates in
thousands
% change from
2000
% change from
1996-2000 mean
Mallard 10.3 -51.5 -66.2
American black duck 182.6 -29.2 -24.1
American wigeon 59.5 125.4 558.8
American green-winged teal 145.9 6.9 1.2
Northern pintail 14.2 117.7 139.7
Ring-necked duck 127.9 -41.0 -28.9
Goldeneye 149.6 164.2 65.3
Bufflehead 25.3 97.2 149.4
Scoters 11.6 -30.5 -60.5
Mergansers 44.9 -13.9 -46.9
Total Ducks 801.5 -12.2 -15.4
Canada goose 155.9 -20.8 -30.5
NAP Canada goose (Strata
66 and 67)
129.3 -26.4 -31.9
METHODS
Methods for conducting this survey are described in the Standard Operating Procedures
for Aerial Waterfowl Breeding Ground Population and Habitat Surveys in North America,
Section III, revised 1987. Waterfowl data was collected using Hodges (2001) Voice/GPS
(record and transcribe) survey system designed to georeference each observation. Transcribed
raw data was error checked and compiled for transmission to the Population and Habitat
Assessment Section (PHAS) of the United States Fish and Wildlife Service (USFWS), Division
of Migratory Bird Management (DMBM).
This years data was adjusted with pooled visibility correction factors for Strata 62 and 63
through 67. This is the second operational survey for Strata 62 through 67, however it must be
noted that comparisons are made with a minimum of historical data. Stratum 62 has a data set
from 1995-2001 while Strata 63-67 have data sets from 1996-2001. A discussion of North
Atlantic Population (NAP) Canada geese is included with Total Indicated Pairs (TIP) and Total
Indicated Birds (TIB) listed in Table 5.
Crew leader John Bidwell, Biologist/Pilot and observer Marty Drut, Wildlife Biologist
worked together for a second consecutive year. Because of increased interest and concern over
American black duck and NAP Canada goose populations, the author suggests that the same
aerial crew be maintained for at least another five years. This would certainly help with the
statistical analysis of population data.
A Partenavia (P68C-TC) aircraft (N766) was used for the survey which began May 2 and
continued through June 2. Twenty one days and 109.3 flight hours were needed to complete all
331 segments as shown in Table 2 (Current Year Design). Weather delays were encountered in
Fredericton, New Brunswick during the middle of May and at Goose Bay, Labrador near the end
of the month. Traditionally, the survey is flown from Maine (Stratum 62) north to Labrador
(Stratum 67), and within each stratum, flown from south to north. The exceptions are Nova
Scotia (Stratum 64) and Prince Edward Island (Stratum 65). Stratum 65 is only 6 segments and
is traditionally flown from north to south, in one day, as progression is made toward Halifax,
Nova Scotia. Once in Halifax (central Nova Scotia) transects for Stratum 64 are flown, first
south to Yarmouth, and then north to Sydney. It should be noted that the final decision on
survey design is based on weather and safety factors.
WEATHER AND HABITAT
Weather conditions in Maine and the Maritimes for the period November 2000 to April
2001 were cool and wet. Mean temperatures ran slightly below normal but snowfall was
considerably above 2000 levels and in many areas above long term averages. For example, the
Avalon peninsula of Newfoundland had between 6 and 6.5 meters of snow from October through
April. All other Atlantic provinces and Maine recorded heavy precipitation averaging from 2.5
to 4.6 meters of snow.
Through the end of April, spring thaw was late to arrive and snow and ice remained in
most areas except coastal habitats. During the first week of May, however, above normal
temperatures (30 degrees Celsius) created rapid snow and ice melt in the inland areas of Strata 62
to 65. The thaw was so rapid that much of the snow pack evaporated creating extreme, but
temporary, spring fire problems in Maine and New Brunswick. Temporary, because from May
13 to 15 a low pressure stalled over Maine and the Maritimes dumping as much as 100
millimeters of rain in a twenty four hour period in Moncton, New Brunswick and Halifax Nova
Scotia. Rainfall records were broken all the way back to 1964. New Brunswick and parts of
Nova Scotia went from tinder dry to flooded conditions in two days.
Winter in Labrador was about normal for precipitation and temperature. Spring thaw,
however, in Newfoundland and Labrador (Strata 66 and 67) were about a week late based on
long term averages. Like the Maritimes, Labrador had high temperatures (above 20 degrees
Celsius) the last week of May, breaking records back to the 1940’s.
Habitat condition and duck phenology appeared at least a week late throughout the
survey area. Most birds were recorded as singles and pairs and large flocks of migrating birds
were not noticed on transect. However, concentrations of most duck species common to the
north east were noticed along the Saint John River in New Brunswick and also around coastal
wetlands of all strata. In most cases these birds were not recorded because of survey design and
appeared either to be late or non breeders.
BREEDING POPULATION ESTIMATES
Data for the 2001 breeding waterfowl population are listed by strata and species in Table
1 and the long term population estimates can be found in Appendix 1. The overall duck
population estimate for 2001 is 801,500 which is (-12.2%) less than 2000 and (-15.4%) less than
the long term (1996-2000) mean. American black ducks are down (-29.2%) from 2000 to an
index of 182,600 and also down (-24.1%) from the long term mean. Three dabbler species
increased in 2001. American wigeon set a survey record at 59,500 which is (+125.4%) above
2000 and (+558.8%) above the long term mean. American green-winged teal also showed a
moderate increase of (+6.9%) over 2000 and (+1.2%) over the long term mean. Northern
pintails, primarily along the western side of Labrador, increased (+117.7%) over 2000 and
(+139.7%) over the long term mean. In the diving duck category Ring-necked duck declined
(-41.0%) over 2000 to an index of 127,900. This is also a (-28.9%) decrease over the long term
mean. Goldeneye and Bufflehead, however, both showed increases over the 2000 index and the
long term mean. In the miscellaneous category, Scoters declined in Stratum 67 to a survey low
of 11,600 which is (-30.5%) below the 2000 index and (-60.5%) below the long term index.
Figure 1 shows population indices for individual waterfowl species on an annual basis and can
be found at the end of this report.
The North Atlantic Population (NAP) Canada geese breed in western Greenland,
Labrador, Newfoundland and eastern Quebec and over-winter in southern Atlantic Canada and
New England. Tables 3 and 4 present raw and expanded data for NAP Canada geese in Stratum
66 (Newfoundland) and Stratum 67 (Labrador) respectively. Table 5 summarizes and combines
these data sets and shows that the Total Indicated Pairs (TIP) index is essentially unchanged
from 2000 at 57,797, however, it is (-22.4%) below the 1996-2000 mean. Total Indicated Birds
(TIB) fell to 129,258 which is a (-26.4%) decline over 2000 and a (-31.9%) decline over the long
term mean.
CONCLUSIONS
A late spring and isolated flooding in New Brunswick and Nova Scotia during May could
have adversely affected early nesting species, but in general habitat conditions were good
throughout Maine and the Atlantic provinces. Late nesting should be successful and at least
average production can be expected. The NAP Canada geese Total Indicated Bird index fell
below the 2000 and the long term average, however Total Indicated Pairs remained at the 2000
level, so production should remain stable.
ACKNOWLDGEMENTS
I would like to thank Bruce Turner, Scott Gilliland and Myrtle Bateman of the Canadian
Wildlife Service (Atlantic Region) for assistance and advice during this survey. Also, thanks to
all the DMBM staff who assisted me in preparation of this final report.
Submitted by: John Bidwell, Flyway Biologist July 18, 2001
Table 1. Status of waterfowl breeding population estimates (thousands, adjusted for visibility bias) by species and stratum.
Stratum % Change From
Species/Ponds 62 63 64 65 66 67 2001 Total 2000 Total 1996-2000 Mean 2000 1996-2000 Mean
Ducks
Dabblers
Mallard 6.3 2.1 1.4 0.5 0.0 0.0 10.3 21.1 30.3 -51.5% -66.2%
Am. black duck 30.8 23.4 7.9 5.9 17.9 96.8 182.6 257.8 240.6 -29.2% -24.1%
Gadwall 0.0 0.7 0.0 0.0 0.8 1.5 3.0 0.0 0.3 -- 831.7%
Am. wigeon 1.1 18.6 5.6 2.8 25.7 5.7 59.5 26.4 9.0 125.4% 558.8%
Am. green-winged teal 20.0 25.9 26.5 4.4 5.6 63.7 145.9 136.5 144.2 6.9% 1.2%
Blue-winged teal 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 9.7 -- -100.0%
N. shoveler 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.1 0.6 -100.0% -100.0%
N. pintail 0.0 1.2 1.0 0.0 0.0 12.0 14.2 6.5 5.9 117.7% 139.7%
Subtotal 58.1 71.8 42.3 13.6 49.9 179.7 415.5 450.5 440.7 -7.8% -5.7%
Divers
Redhead 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 -- --
Canvasback 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 -- --
Scaups 0.0 0.0 0.0 0.0 0.0 0.0 0.0 17.5 5.4 -100.0% -100.0%
Ring-necked duck 33.8 16.5 8.9 3.3 19.7 45.7 127.9 216.7 180.0 -41.0% -28.9%
Goldeneyes 1.5 8.2 0.0 0.0 52.9 87.1 149.6 56.6 90.5 164.2% 65.3%
Bufflehead 16.5 0.0 0.0 0.0 0.0 8.9 25.3 12.8 10.2 97.2% 149.4%
Ruddy Duck 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 -- -100.0%
Subtotal 51.7 24.7 8.9 3.3 72.6 141.7 302.9 303.7 286.6 -0.2% 5.7%
Miscellaneous
Oldsquaw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.6 -- -100.0%
Eiders 26.7 0.0 0.0 0.0 0.0 0.0 26.7 89.8 105.3 -70.3% -74.7%
Scoters 0.4 0.0 0.0 0.2 0.0 10.9 11.6 16.6 29.3 -30.5% -60.5%
Mergansers 6.9 2.2 3.3 0.2 5.5 26.8 44.9 52.2 84.6 -13.9% -46.9%
Subtotal 33.9 2.2 3.3 0.5 5.5 37.7 83.1 158.6 219.8 -47.6% -62.2%
Total Ducks 143.8 98.8 54.6 17.3 128.0 359.1 801.5 912.7 947.1 -12.2% -15.4%
Canada Goose 18.0 2.4 4.3 2.0 57.4 71.9 155.9 196.9 224.3 -20.8% -30.5%
Am. coot 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 -- --
Table 2. Survey design for Maine and the Maritimes, May 2001.
Stratum
Survey Design 62 63 64 65 66 67 Total
Square miles in stratum 32,202.7 27,874.5 21,179.6 2,225.21 42,248.4 84,608.8 210,339.21
Square miles in sample 333 256.5 216 27 319.5 337.5 1,489.5
Linear miles in sample 1,332 1,026 864 108 1,278 1,350 5,958
Number transects in sample 11 8 10 3 10 7 49
Number segments in sample 74 57 48 6 71 75 331
Expansion factor 96.705 108.673 98.054 82.415 132.233 250.693 141.215
Current Year Design
Square miles in stratum 32,202.7 27,874.5 21,179.6 2,225.21 42,248.4 84,608.8 210,339.21
Square miles in sample 333 256.5 215.25 27 319.5 337.5 1,488.75
Linear miles in sample 1,332 1,026 861 108 1,278 1,350 5,955
Number transects in sample 11 8 10 3 10 7 49
Number segments in sample 74 57 48 6 71 75 331
Expansion factor 96.705 108.673 98.395 82.415 132.233 250.693 141.286
Table 3. North Atlantic Population Canada goose breeding survey data, stratum 66.
Raw data Expanded data
Stratum Year Singles Pairs Open TIP* TIB**
Expansion
factor VCF*** Singles Pairs Open TIP* TIB**
66 1996 11 47 0 58 116 234.7111 2.73 7,048 30,116 0 37,164 74,328
66 1997 14 32 4 46 96 223.5344 2.73 8,543 19,528 2,441 28,071 58,584
66 1998 28 62 71 90 251 132.2316 2.73 10,108 22,382 25,630 32,489 90,609
66 1999 59 46 45 105 255 132.2316 2.73 21,299 16,606 16,245 37,904 92,053
66 2000 36 45 38 81 200 132.2316 2.73 12,996 16,245 13,718 29,240 72,198
66 2001 39 32 17 71 159 132.2316 2.73 14,079 11,552 6,137 25,630 57,398
* Total indicated pairs = S + P
** Total indicated birds = 2S + 2P + O
*** Visibility correction factor
Expanded data = (Raw data) x (Expansion factor) x VCF
Table 4. North Atlantic Population Canada goose breeding survey data, stratum 67.
Raw data Expanded data
Stratum Year Singles Pairs Open TIP* TIB**
Expansion
factor VCF*** Singles Pairs Open TIP* TIB**
67 1996 12 50 37 62 161 368.6623 2.73 12,077 50,322 37,239 62,400 162,038
67 1997 22 29 30 51 132 261.1358 2.73 15,684 20,674 21,387 36,358 94,103
67 1998 19 11 52 30 112 261.1358 2.73 13,545 7,842 37,071 21,387 79,845
67 1999 45 41 6 86 178 250.6904 2.73 30,797 28,060 4,106 58,857 121,820
67 2000 13 29 67 42 151 250.6904 2.73 8,897 19,847 45,854 28,744 103,342
67 2001 20 27 11 47 105 250.6904 2.73 13,688 18,478 7,528 32,166 71,860
* Total indicated pairs = S + P
** Total indicated birds = 2S + 2P + O
*** Visibility correction factor
Expanded data = (Raw data) x (Expansion factor) x VCF
Table 5. North Atlantic Population Canada goose breeding survey data combined
for Strata 66 (Newfoundland) and 67 (Labrador)
Stratum 66 (Newfoundland)
Year Singles Pairs Grouped TIP* TIB**
1996 7,048 30,116 0 37,164 74,328
1997 8,543 19,528 2,441 28,071 58,584
1998 10,108 22,382 25,630 32,489 90,609
1999 21,299 16,606 16,245 37,904 92,053
2000 12,996 16,245 13,718 29,240 72,198
2001 14,079 11,552 6,137 25,630 57,398
Stratum 67 (Labrador)
Year Singles Pairs Grouped TIP* TIB**
1996 12,077 50,322 37,239 62,400 162,038
1997 15,684 20,674 21,387 36,358 94,103
1998 13,545 7,842 37,071 21,387 79,845
1999 30,797 28,060 4,106 58,857 121,820
2000 8,897 19,847 45,854 28,744 103,342
2001 13,688 18,478 7,528 32,166 71,860
Combined total, strata 66 and 67
Year Singles Pairs Grouped TIP* TIB**
1996 19,126 80,438 37,239 99,564 236,366
1997 24,227 40,202 23,828 64,429 152,687
1998 23,653 30,223 62,701 53,876 170,454
1999 52,096 44,665 20,351 96,761 213,874
2000 21,893 36,092 59,571 57,985 175,541
2001 27,766 30,030 13,665 57,797 129,258
* Total indicated pairs = Singles + Pairs
** Total indicated birds = 2 x Singles + 2 x Pairs + Grouped
Appendix 1. Long-term trend in adjusted waterfowl breeding population estimates
(thousands).
Species/Ponds 1996 1997 1998 1999 2000 2001
Ducks
Dabblers
Mallard 23.1 38.2 48.0 21.3 21.1 10.3
Am. black duck 178.2 261.4 288.7 216.8 257.8 182.6
Gadwall 0.0 0.8 0.8 0.0 0.0 3.0
Am. wigeon 3.2 2.7 9.2 3.7 26.4 59.5
Am. green-winged teal 149.4 90.0 170.0 175.2 136.5 145.9
Blue-winged teal 22.3 1.8 5.6 19.0 0.0 0.0
N. shoveler 0.7 0.0 0.0 0.0 2.1 0.0
N. pintail 9.1 2.2 1.7 10.2 6.5 14.2
Subtotal 386.0 397.0 524.0 446.2 450.5 415.5
Divers
Redhead 0.0 0.0 0.0 0.0 0.0 0.0
Canvasback 0.0 0.0 0.0 0.0 0.0 0.0
Scaups 0.0 0.4 0.6 8.7 17.5 0.0
Ring-necked duck 175.4 246.7 132.4 128.7 216.7 127.9
Goldeneyes 31.2 45.3 83.3 236.3 56.6 149.6
Bufflehead 3.4 8.0 3.1 23.4 12.8 25.3
Ruddy Duck 0.0 0.0 0.0 2.3 0.0 0.0
Subtotal 210.0 300.4 219.5 399.4 303.7 302.9
Miscellaneous
Oldsquaw 1.5 0.0 1.4 0.0 0.0 0.0
Eiders 172.9 95.4 168.3 0.0 89.8 26.7
Scoters 23.3 0.0 60.7 45.8 16.6 11.6
Mergansers 45.9 149.7 107.3 68.2 52.2 44.9
Subtotal 243.6 245.0 337.7 114.0 158.6 83.1
Total Ducks 839.6 942.4 1081.2 959.6 912.7 801.5
Canada Goose 231.7 185.1 229.2 278.8 196.9 155.9
Am. coot 0.0 0.0 0.0 0.0 0.0 0.0
Strata 62-67 Mergansers
Population
40000
50000
60000
70000
80000
90000
100000
110000
120000
130000
140000
150000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Mallard
Population
0
10000
20000
30000
40000
50000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 American black duck
Population
0
100000
200000
300000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Gadwall
Population
0
1000
2000
3000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 American wigeon
Population
0
10000
20000
30000
40000
50000
60000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 American green-winged teal
Population
0
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
110000
120000
130000
140000
150000
160000
170000
180000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Blue-winged teal
Population
0
10000
20000
30000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Northern pintail
Population
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
11000
12000
13000
14000
15000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Scaups
Population
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
11000
12000
13000
14000
15000
16000
17000
18000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Ring-necked duck
Population
0
100000
200000
300000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Goldeneyes
Population
0
100000
200000
300000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Bufflehead
Population
0
10000
20000
30000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Scoters
Population
0
10000
20000
30000
40000
50000
60000
70000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Canada Goose
Population
0
100000
200000
300000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Dabblers
Population
0
100000
200000
300000
400000
500000
600000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Divers
Population
0
100000
200000
300000
400000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Miscellaneous
Population
0
100000
200000
300000
400000
Year
1995 1996 1997 1998 1999 2000 2001
Strata 62-67 Total Ducks
Population
200000
300000
400000
500000
600000
700000
800000
900000
1000000
1100000
Year
1995 1996 1997 1998 1999 2000 2001