1 Articles

The Black Scoter in Northern Ontario by R. Kenyon Ross

Introduction second survey of these flocks to The Black Scoter (Melanitta nigra monitor any changes in this segment americana1is a duck that can be of the population. These results are found at various times of the year in presented in this paper along with many parts of Canada and yet it some observations of potential remains a species of considerable breeding pairs in northern Ontario. mystery. Unlike the European race Methods (M. n. nigra), whose life history and distribution has been well The survey took place on 29 and 30 documented (Cramp 1977), the North July 1991 and employed the timing American race presents unanswered and technique largely similar to that questions regarding such basic facts used in 1977 (Ross 19831. The flight as breeding and wintering was conducted in a DeHavilland distributions. Godfrey (19861 still DHC-6 Twin Otter flying at describes its Canadian breeding range approximately 160 km/h and at least in terms of local sightings scattered 150 m ASL so as not to cause diving across the north. Description of the by the ducks. As the flocks were wintering distribution remains visible from a considerable distance, essentially at the qualitative stage and total coverage was attempted by indicates that most of these scoters following a zig-zag course along the occur along the American coasts with coast, covering a band extending particular concentrations around the from the shoreline to approximately Aleutians, and along the Atlantic 15 km offshore. Visibility was very shore of Georgia and the Carolinas good on both days. Weather (Bellrose 19801. The only other conditions were as follows: 29 July substantial concentrations of Black (survey duration, UOO-1830hl Scoters documented in North -sunny, warm, winds light becoming America are the flocks of moulting moderate in late afternoon; 30 July birds found along the coasts of James (survey duration, 1l00-1200hl - high and Hudson Bays (Smith 1944; overcast, warm, calm. Manning 19521. An initial Almost all flocks were photographic survey of these birds photographed with a hand-held (Ross 19831 enumerated a minimum 35mm camera (Olympus OM-2, of 88,700 male Black Scoters along 135mm lens, Kodachrome 64 filml. the northern coast of Ontario during The photographer sat in the copilot's late July 1977. In 1991, an seat of the aircraft which was flown opportunity arose to undertake a directly over the flocks to allow for

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an almost vertical camera angle. A levels have changed little over this second observer made visual time period. estimates of the few small flocks that, The distribution of the scoter because of their positions, could not flocks is illustrated in Figure 1, which be placed on the right side of the shows the coastline divided into 16 aircraft for photographing without sectors where the scoters occurred. undue and disruptive circling. The All four locations that held scoters in location of the aircraft throughout the 1977 were also used in 1991 survey was monitored by satellite although numbers at each si~e were navigation (GPS). The photographed duc~s were enumerated by projecting quite different. The most southerly the Images of the flocks onto plain (Longridge Point - Sector 16) and paper, and marking and afterwards northerly (Kettle River -Sector 1) held counting all identifiable ducks. Where much higher numbers than before, multiple photographs were needed to while counts were lower in the other cover a larger flock, the resulting two (Ekwan to Hook Point - Sectors representations on paper were 8-14, and particularly Shell Brook overlapped and boundaries -Sector 5). As well, four new sites established to eliminate double were discovered during the present counting. The number counted survey (Sectors 4, 6, 7, and 15), and should be considered a minimum as a flocks were seen fairly continuously few small flocks may have been from east of the Pen Islands to the missed and some birds may have Kettle River (Sectors 1 to 3), all of been underwater at the moment of which. sug?est considerable variability over tIme 10 the use of moulting sites. photography; feeding activity tended It may be that intense use of certain to subside toward the middle of the sites sufficiently reduces food day, thus reducing the number diving resources to cause redistribution of a (Ross 1983). portion of the birds. There have been no feeding studies of these moulting Results and Discussion scoters although it is expected that This survey revealed 69,910 male they are eating molluscs such as the Black Scoters in moulting flocks along blue mussel (Mytilus edulis) and the actual Ontario coast of James and Hudson Bays with a further 17,620 possibly the clam, Macoma baltica. off the mouth of the Kettle River in Also, there is likely a sequential Manitoba (Table 1). This total for movement between moulting sites, Ontario is substantially lower than probably from north to south, as that recorded in 1977 (88,700) birds regain the powers of flight; thus although when one includes the annual phenological shifts in the Kettle River birds the totals are more breeding cycle would also influence comparable (91,200 in 1977; 87,530 numbers in an area at any given in 1991). As it is possible that these time. This pattern of numbers ducks may from year to year use peaking in late July and dropping different moulting sites, particularly during August was observed at Longridge Point (Ross 1983). those near each other, it is probably best to compare overall numbers The origin of these ducks remains which would suggest that population unclear although the relatively high

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Table 1. Comparison of Results of 1977 and 1991 Surveys of Moulting Black Scoters along the Northern Coast of Ontario and Contiguous Manitoba.

Sector Counts of Moulting Black Seaters

1991 1977

17620 2500*

2 2210

3 3950

4 1420

5 6180 43700

6 940

7 1250

8 7650 N/A

9 490 N/A

10 1730 N/A

11 8110 N/A

12 8610 N/A

13 5530 N/A

14 5520 N/A

Subtotal sectors 8 - 14 37640 42600

15 7730

16 8590 2400

Total 87530 91200

* Estimates taken from Vaught and Arthur in Bellrose 1980

VOLUME 12 NUMBER 1 0 I I I I I I I I I ~ z 90' 88' 86' 84' 82' 80' 18' 76' 7f.' >-3 [58' 56'4 a~ el ~ I Numbers of en >- Moulting Black Scoters "tl ::l:l t:: 490 - 999 .... 4 • \D 1000 - 1999 \D I 54 -l>- • 56' 2000 - 3999 •• • 4000 - 7999 0 0 0 • 8000 - 15999 00 0 0 0 0 0 • 16000 + O~ 52' 5(' (a • ~

0 ~ I .-,.,(...1 Locations of Sightings of 16~ Potential Breeding Pairs \ --- so' 52' 1 I 0 1980's surveys - positive IO 0 1993 survey - positive IO 0 2.00 Jon 1993 - IO I \ I I • survey not ---positive 90' 88' 86' 8(' 82' 80' \ 78' 76'

Figure 1: Distribution of moulting Black Scoters as determined during 1991 survey, and location of sightings of potential breeding pairs. 5

Table 2. Observations by R.K. Ross of Potential Breeding Pairs of Black Scoters In the Hudson Bay Lowlands of Ontario.

Observation 10 Date Coordinates

Confirmed Lat. Long. (v')

1 pair v' May 21 1982 52 0 42' 850 14'

1 lone male v' June 01 1987 540 18' 840 51'

1 pair v' June 01 1987 540 30' 850 09'

1 pair v' June 01 1987 540 51' 850 07'

1 pair v' June 01 1987 540 51' 840 30'

1 pair v' June 02 1988 54 0 30' 880 32'

3 pairs v' June 02 1988 540 31' 870 36'

2 pairs v' June 02 1988 540 52' 870 37'

1 pair v' June 02 1988 54 0 52' 870 19'

2 pairs v' June 061993 540 41' 850 09'

3 pairs v' June 07 1993 550 10' 860 35'

4 pairs June 071993 55 0 25' 870 24'

1 lone bird June 071993 55 0 40' 890 32'

1 lone bird June 07 1993 55 0 45' 890 17'

1 pair v' June 07 1993 560 24' 890 14'

2 pairs June 071993 560 28' 880 51' breeding densities recorded in the Lac Most of my records were made Bienville area of northern Quebec during waterfowl breeding pair (>13 pairs/lOO km2) by Savard and surveys of northern Ontario which Lamothe (1991) point to that area as a employed a systematically located possible source of moulters. To date, grid of survey blocks (methods and there has been no confirmed breeding block locations described in Ross and record of Black Scoters in Ontario; Fillman 1990). A projection based on however, I have made several these samples yields a population observations of potentially breeding estimate of 6500 pairs although this is pairs in suitable habitat (see Table 2). very approximate given the high variance.

VOLUME 12 NUMBER 1 6 One should also note that these initiation (mid-June) and brood surveys took place in late May and rearing (mid-July) to determine early June while the first lone male conclusively the status and Black Seoters-. did not arrive in the abundance of this interesting species, Lac Bienville area until 11 June and improve our knowledge of other (Savard and Lamothe 1991.1. It is, late-nesting waterfowl. therefore, likely that many birds may not yet have arrived in northern Ontario, thus lowering the estimate of potential breeding numbers. It would Acknowledgements still seem unlikely that an additional This survey was a joint effort of the 80,000 breeding pairs of these scoters Canadian Wildlife Service would return and yet go virtually (Environment Canada) and the unrecorded. Instead it is more Ontario Ministry of Natural probable that there are some local Resources as part of the Habitat breeding concentrations of Black Based Assessment of Ontario's Scoters in the Hudson Bay Lowlands Subarctic Coast Project. I am very which are supplemented on the grateful to the Ontario Ministry of moulting grounds by Quebec birds, Natural Resources staff at the particularly along the James Bay Moosonee office, particularly Nancy coast. Wilson, the project co-ordinator, Jim The distribution of sightings of Leafloor, the regional waterfowl potential breeding pairs of Black biologist, and our pilot, Denis Scoters is presented in Figure 1 and Ladouceur. Thanks also to Guy includes both my waterfowl survey Morrison for his help with observations from the 1980's and observations during the photo survey, some records made by J. Leafloor and and to my observers on the breeding myself in 1993 during the course of a pair surveys, in particular, Don goose survey; records of probable Fillman, Steve Wendt, and Steve Black Scoters from 1993 are also O'Donnell. Lastly, I especially thank included for interest. Although Barb Campbell who did the photo coverage of the likely breeding area analysis, and prepared the map and in the Ontario Hudson Bay Lowlands the tables. is not complete, the observations made so far do show some relationship to the moulter Literature cited distribution in that they mostly occur Bellro~, F.e. 1980. Ducks, Geese and Swans near headwaters of rivers around of North America. Stackpole Books, whose estuaries the moulters Harrisburg, PA. congregate. Only the two Cramp, S. (Chief ed.J. 1977. Handbook of the Birds of Europe, the Middle East, and North southernmost sectors show no Africa: the Birds of the Western Palearctic. potential breeding pair records from Volume I: Ostrich to Ducks. Oxford the immediate hinterland and may University Press, New York. indicate that these birds are mostly of Godfrey, W.E. 1986. The Birds of Canada. Quebec origin. Clearly, specific Second Edition. National Museums of surveys are needed throughout the Canada, Ottawa. Ontario lowlands both during nest

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Manning, T.H. 1952. Birds of the West James Savard,J.L. andP. Lamothe. 1991. Distribution, Bay and Southern Hudson Bay Coasts. abundance, and aspects of breeding ecology National Museum of Canada Bulletin 125. of Black Scoters, Melanitta nigra, and Surf Ross, R.K. 1983. An estimate of the Black Scoter, Scoters, M. perspicillata, in northern Quebec Melanitta nigra, population moulting in James Canadian Field-Naturalist 105: 488-496. and Hudson Bays. Canadian Field-Naturalist Smith, R.H. 1944. An Investigation of the 97: 147-150. Waterfowl Resources of the West Coast of James Bay 1944. Unpublished report to the Ross" R.K. and D. Fillman. 1990. Distribution ""I Canadian Wildlife Service. of American Black Duck and Mallard in northern Ontario. Canadian Wildlife Service Progress Note 189.

R. Kenyon Ross, Canadian Wildlife Service, Ontario Region 49 Camelot Drive, Nepean, Ontario KIA OH3

Sharp-shinned Hawk Declines: An Inland Perspective by Allen Chartier

Much has been written about the and some potential causes of declines declines of Sharp-shinned Hawk are discussed. (Accipiter striatus) at coastal sites, Season totals at Holiday Beach for particularly at Cape May, New Jersey Sharp-shinned Hawks have remained (Kerlinger in Winging It, September relatively stable over the past 20 1993). Additionally, theories to years of organized counts. The 20 explain the differences in the declines year average is about 13,000. Note between the coastal and inland sites the relative stability of the. Holiday have been attributed to the higher Beach totals compared with the proportion of adults at inland sites extreme declines at Cape May against (Hawk Mountain data, after their 20 year average of about 32,000 Heintzelman), noted as up to a 50/50 (Figure 1). ratio. To date, there has not been any Sharp-shinned Hawks have been widely published data regarding the aged on the wing by observers at age ratio of Sharp-shinned Hawks Holiday Beach since 1988. Observer migrating through the Great Lakes effort has been remarkably region. The purpose of this paper is consistent, with between 90 and 95 to provide such information for days covered in each year. The ability Holiday Beach Conservation Area, to age birds has varied from year to Ontario to clarify the situation. In year, and depends on many variables addition, reasons for these differences

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