31 Notes

Ground Nesting by Bald Eagles

Chris Martin

During the summer of 2004, I the island, approximately two metres worked in Quetico Provincial Park, above the waterline. A juvenile Bald Rainy River District, in northwest­ Eagle sat on one side of the nest. The ern Ontario, researching forest stand island was a small rock dome, com­ history, shoreline succession and lake pletely devoid of vegetation, and had outlets. While working on Pickerel a few large boulders scattered on it Lake near the northern boundary of (Figure 1). The nest was made of the park, a co-worker informed me sticks of various sizes and had a that as he was canoeing past a small, rather flattened appearance, possibly treeless rocky island, a Bald Eagle due to the activities of the young (Haliaeetus leucocephalus) flew out eagle. The nearest adjacent land was directly toward him in a threatening one kilometre away. manner and returned to the island. Believing this to be unusual behav­ Discussion iour, he wondered if it might be nest­ Bald Eagles are a fairly common ing on the island. Later that evening, breeding bird in Quetico Provincial I paddled out with this co-worker to Park and northwestern Ontario the island. This produced an identi­ (Elder 1994). Nests are usually con­ cal unnerving response from the structed in the biggest locally avail­ adult eagle. Using binoculars, I fol­ able tree. In the park, White Pine lowed the eagle as it flew back to the (Pinus strobus) is the nest tree of island and saw it land next to a large choice followed by large Trembling stick nest, step into it and settle down Aspen (Populus tremuloides). as if to incubate eggs. Occasionally, another tree species My second opportunity to view may be used. There is no previous the nest came on a very windy 22 record of a Bald Eagle nest on the June en route to another lake. ground in Quetico or elsewhere in Armed with a digital camera, anoth­ Ontario (Peck, 2004; pers. comm.). er co-worker and I fought the wind The species has a vast range in to gain a much closer east-facing per­ North America and tree nesting is spective of the nest, scaring off one the norm. Big trees are necessary to adult eagle in the process. A large support the large size of the nest stick nest sat on the highest part of that if used for many years can

VOLUME 23 NUMBER 1 32

Figure 1: Juvenile Bald Eagle on ground nest, Pickerel Lake, Quetico Provincial Park, 22 June 2004. Photo by Chris Martin. become extremely heavy. A nest Reservoir (Laing et a1. 2003). Bald used for many years in Ohio, Eagles have been reported nesting U.S.A. was estimated to weigh on the ground: near the shore of a more than 2 tonnes after it and its rocky island in Great Slave Lake, supporting tree were felled by a Northwest Territories (Bromley and windstorm (Stalmaster 1987). Trauger 1974); rarely (three out of However, Bald Eagle nests have 206 nests studied) on small islets been found previously that were not (keys) in Florida Bay (Curnutt and built in trees (Buehler 2000). In Robertson 1994); and in a cornfield Newfoundland, nests have been in northwestern Minnesota (Hines observed on steep cliffs (Peters and and Lipke 1991). A nest found on a Burleigh 1951). Cliff nests have been small rocky island in the recorded in Alaska and British Saskatchewan River appeared to be Columbia also (Campbell et a1. similar to the one in Quetico 1990) and in Baja California, a nest (Gerrard and Bortolotti 1988). was built in a giant cactus (Palmer Why this pair of Bald Eagles 1988). In west-central Labrador, chose to nest on the ground is open to both Bald Eagles and Ospreys speculation. Bald Eagle populations (Pandion haliaetus) nest on large have been increasing significantly in rock pinnacles in the Smallwood northwestern Ontario and it is possi- o TARIO BIRDS APRIL 2005 33 ble that suitable nesting trees in the Ospreys are uncommon breeders in Pickerel Lake area of Quetico have Quetico (Elder 1994), and there is an all been taken by other pairs. It may abundance of suitable nest trees. have been the relative isolation and In any event, it will be interesting security the island site provided that to see whether what may be the only made it more attractive than nearby ground nest of Bald Eagles in suitable trees. The lack of mam­ Ontario continues to be used in the malian predators in the Aleutian future. Islands (Sherrod et al. 1977) and on keys in Florida Bay (Curnutt and Acknowledgements Robertson 1994) was presumed to Dave Elder and Ron Tozer kindly enable ground nesting by Bald assisted with the preparation of this Eagles. It is possible that Ospreys article, and Dawn Laing provided first built the nest and the eagles took information on ground nesting Bald it over, but this seems unlikely since Eagles in Labrador.

Literature Cited Bromley, R.G. and D.L. Trauger. 1974. Hines, P. and H. Lipke. 1991. Ground-nest­ Ground nesting of Bald Eagles near ing Bald Eagles in northwestern Yellowknife, Northwest Territories. Minnesota. Loon 63: 155-157. Canadian Field-Naturalist 88: 73-75. Laing, O.K., D.M. Bird, T.E. Chubbs and G. Buehler, D.A. 2000. Bald Eagle (Haliaeetus Humphries. 2003. Migration routes, tim­ leucocephalus). In The Birds of North ing and nest fidelity of Osprey (Pandion America, No. 506 (A. Poole and F. Gill, haliaetus) and Bald Eagles (Haliaeetus editors). The Birds of North America, leucocephalus) as they relate to military Inc., Philadelphia, Pennsylvania. aircraft activity in Labrador. Argos Campbell, R.W., N.K. Dawe, I. McTaggart­ Animal Tracking Symposium, Annapolis, Cowan, J.M. Cooper, G.W. Kaiser, and Maryland, March 24-26, 2003. M.C.E. McNall. 1990. The Birds of British Palmer, R.S. (editor). 1988. Handbook of Columbia. Volume 2. Nonpasserines: North American Birds. Volume 4. Diurnal Diurnal Birds of Prey Through Raptors (Part 1). Yale University Press, Woodpeckers. University of British New Haven, Connecticut. Columbia Press, Vancouver. Peters, H. S. and T.D. Burleigh. 1951. The Curnutt, J.L. and W.B. Robertson, Jr. 1994. Birds of Newfoundland. Department of Bald Eagle nest site characteristics in Natural Resources, St. John's, south Florida. Journal of Wildlife Newfoundland. Management 58: 218-221. Sherrod, S.K., C.M. White, and F.S.L. Elder, D.H. 1994. The Birds of Quetico Williamson. 1977. Biology of the Bald Provincial Park and the Atikokan Area. Eagle on Amchitka Island, Alaska. The Friends of Quetico Park, Atikokan, Living Bird 15: 143-182. Ontario. Stalmaster, M.V. 1987. The Bald Eagle. Gerrard, J.M. and G.R. Bortolotti. 1988. The Universe Books, New York. Bald Eagle: Haunts and Habits of a Wilderness Monarch. Western Producer Prairie Books, Saskatoon, Saskatchewan.

Chris Martin, 130 Balsam Road, Box 1065, Atikokan, Ontario, POT 1CO

VOLUME 23 NUMBER 1 34

An Apparent Bumehead x Common Goldeneye Hybrid

Kevin McLaughlin, George Naylor and Bill Lamond

On 11 January 2004, the authors get on the bird and a lively discus­ were once again counting water­ sion ensued regarding its identity. fowl in the Hamilton Study Area as The notion that it might be an alcid part of the Lake Ontario Midwinter was quickly discarded, with the Waterfowl Census, of which GN is acceptance that the bird was an the regional compiler. The unusual hybrid diving duck. Hamilton area is divided into three sections for this census, and three Description participant groups rotate through The duck was slightly but obviously these different areas on a yearly smaller than the male Common basis. The authors have been a cen­ Goldeneyes. The crown, nape, chin sus team for a number of years, and and throat were black and the eye in 2004 our area of responsibility appeared dark as well. Much of the was the north shore of Lake side of the head was whitish, clearly Ontario from the Burlington Ship lacking any semblance of the char­ Canal to Bronte Harbour. acteristic goldeneye facial spot. The The first stop after lunch was bill was smaller than that of a Sioux Lookout on the Burlington Common Goldeneye, black in shoreline. The usual format is for colour, and seemed rather narrow. the three observers to divide up the The head shape seemed rounder species. For example, GN would with a flatter crown and also was count geese and dabbling ducks, noticeably smaller. The back was BL would take care of certain black and the scapulars were broad­ species of diving ducks, and KM ly white, lacking the black "slashes" would count the remainder. The so evident on male Common time was approximately 1300h Goldeneyes. The chest, flanks and when the group started counting underparts were gleaming white. waterfowl. As the duck neither flapped its KM was the first to spot an wings nor flew during the observa­ unusual diving duck which was tion, the makeup of the upperside swimming among many Common of the wing could not be deter­ Goldeneyes (Bucephala clangula), mined. roughly 300 m from shore. His first After more discussion regard­ thought was that it resembled an ing the duck, the conclusion alcid. BL and GN were both able to reached was that the bird was a

ONTARIO BIRDS APRIL 2005 35

Figure 1: Presumed male Bumehead x Common Goldeneye hybrid that was shot off the coast of Washington state near Deception Pass in early January 1998. Photo by Patrick Pitt. hybrid, most likely involving bility of a photograph being Bufflehead (B. a/beo/a) and obtained. The photo included in Common Goldeneye, and that it this note shows a mounted speci­ was a male. That a Barrow's men (Figure 1). That bird was shot Goldeneye (B. is/andica) could off the coast of Washington state in have been involved had to be con­ January 1998. It is very similar to sidered and indeed could not be the Burlington bird except in hav­ ruled out on the basis of plumage ing somewhat less black on the and structural features visible. Our throat, and having a bill seeming to conclusion, however, seemed rea­ match the size of a Common sonable as the most likely case sce­ Goldeneye's. We can only assume nario. As always when a suspected that the golden eye colour of the hybrid is present, a caveat must be specimen represented that of the used; hence the word "apparent" in bird in life. Though quite distant, the title. the Burlington bird always Unfortunately, the bird was not appeared to have a dark eye. As seen again after this first observa­ with the Burlington bird, the speci­ tion, obviously negating the possi- men is believed to be a hybrid

VOLUME 23 UMBER 1 36

female Bufflehead, was in fact a -~'------male Bufflehead in its second cal­ endar year, at or near the end of its :YelelWirms first prealternate molt. The infrequency of reported NATURE STORE 636 Point Pelee Dr. Leamington ON N8H 3V4 hybrids involving Bufflehead in the Birding • Nature • Optics • Books literature contrasts with Common Canada's Largest Selection of Binoculars and Scopes Goldeneye, which hybridizes readi­ All at Discount Prices! ly with several species. It has been suggested that the Bufflehead's small size and distinctive display behaviour probably contribute to reproductive isolation in the species (M.T. Myres in Gauthier 1993). However, given that Bufflehead and Common Goldeneye are in the same genus, are both cavity nesters, and share a large breeding range, hybridization may occur more often than published reports would sug­ gest. Another example of possible involving Bufflehead and Common hybridization involving Bufflehead Goldeneye. was a bird present at Tollgate Ponds, Hamilton Harbour, from 28 Discussion August to 6 September 1999 Gauthier (1993) stated that there (Dobos 2000a, 2000b). Observed by were only two published putative KM and others, this bizarre-looking cases of hybridization involving individual possessed characters sug­ Bufflehead in the wild. One was a gesting parentage of Bufflehead possible Bufflehead x goldeneye and Ruddy Duck (Oxyura known from a wing returned by a jamaicensis). hunter near Thunder Bay, Ontario Wild hybrids have been report­ (Palmer 1976). The other con­ ed involving Common Goldeneye cerned a male bird which was pre­ with Barrow's Goldeneye, Hooded sumed to be a Bufflehead x Merganser, Smew (Mergus albellus), Hooded Merganser (Lophodytes Common Merganser (M. mer­ cucullatus). This individual was ganser), Pochard (Aythya ferina) , found during May in Illinois and Greater Scaup (A. marila) (Marcisz 1981). However, recent (Gray 1958, Palmer 1976, Panov examination of the photographs by 1989, Eadie et a1. 1995), and with the authors has led to the belief that many species in captivity (Gray the bird in question, paired with a 1958). Hybridization occurs most ONTARIO BIRDS APRIL 2005 37 frequently with Barrow's Goldeneye for providing a number of refer­ (Martin and Di Labio 1994, Eadie et ences, Ron Pittaway for critical al. 1995). comments on an earlier draft, Ken Abraham for information and pho­ Acknowledgements tos of hybrids, and Patrick Pitt for We would like to thank Ron Tozer the photograph used in this note.

Literature Cited Dobos, R. 2000a. Noteworthy bird records. Gray, A.P. 1958. Bird hybrids. Technical The Wood Duck 53: 105-108. Communication No. 13. Commonwealth Dobos, R. 2000b. Noteworthy bird records. Agricultural Bureau, Farnham, England. The Wood Duck 53: 127-133. Marcisz, W.J. 1981. A presumed Bufflehead Eadie, J.M., M.L. Mallory, and H.G. x Hooded Merganser hybrid in Illinois. Lumsden. 1995. Common Goldeneye American Birds 35: 340-341. (BucephaLa cLanguLa). In The Birds of Martin, P.R. and H.M. Di Labio. 1994. North America, No. 170 (A. Poole and F. Natural hybrids between the Common Gill, editors). Academy of Natural Goldeneye, BucephaLa cLanguLa, and Sciences, Philadelphia, Pennsylvania, and Barrow's Goldeneye, B. isLandica. American Ornitholo-gists' Union, Canadian Field-Naturalist 108: 195-198. Washington, D.C. Palmer, R.S. 1976. Handbook of North Gauthier, G. 1993. Bufflehead (BucephaLa American Birds. Volume 3. Waterfowl aLbeaLa). In The Birds of North America, (Part 2). Yale University Press, New No. 67 (A. Poole and F. Gill, editors). Haven, Connecticut. Academy of Natural Sciences, Panov, E.N. 1989. Natural Hybridization and Philadelphia, Pennsylvania, and Ethological Isolation in Birds. Nauka, American Ornithologists' Union, Moscow. Washington D.C.

Kevin McLaughlin, 30 Bingham Road., Hamilton, Ontario L8H 1N4

George Naylor, 51 Behan Street, Hamilton, Ontario L8T 4N7

Bill Lamond, 238 St. George Street, Brantford, Ontario N3R 1W7

VOLUME 23 NUMBER 1 38 Can Migration Counts Detect the Effects ofWest Nile Virus?

Allen T. Chartier

According to several sources West Nile Virus in birds is con­ (including the U.S. Centers for firmed only through testing of Disease Control, and Health blood and tissue of dead birds Canada), West Nile Virus was first turned in to local health agencies. detected in North America in New To date, more than 100 species of York in 1999, infecting 62 people birds have tested positive for the and causing 7 deaths. Several thou­ disease. It has been clear that mem­ sand birds, mainly American Crows bers of the family Corvidae (Crows (Corvus brachyrhynchos) were and Jays) are particularly suscepti­ found dead, many confirmed killed ble. Most detections were of dead by the virus through testing of blood American Crows, partly due to the and tissue. The summer and fall (the visibility of dead birds, and partly primary seasons of infection) of due to testing policies of health 2000 saw an expansion of the dis­ agencies. So if migration counts ease through the northeastern U.S., have any potential to show the but it was not detected anywhere in effects of West Nile Virus, members Canada. In 2001, West Nile Virus of the family Corvidae should be was found in Canada for the first ideal subjects. time, mainly in southern Ontario, Annual counts of Blue Jays with 128 dead birds testing positive (Cyanocitta cristata) have been con­ for the disease, but there were no ducted at the Holiday Beach human cases. The 2002 outbreak Migration Observatory (HBMO) was the worst to date, with the near Malden Centre, Essex County, greatest spread of the disease (to Ontario with fairly consistent effort the far western U.S.), and the since 1983. The low count of 72,591 largest number of human casualties. in 2002, which was significantly lower In Canada, dead birds tested posi­ than the previous year's count, drew tive in Ontario, Nova Scotia, commentary from several local Quebec, Manitoba, and Saskatche­ observers that perhaps this might be wan. The 2003 and 2004 seasons due to West Nile Virus. This led to were not as serious as 2002. the natural question, can the effects However, West Nile Virus is clearly of West Nile Virus be detected here to stay, and annual outbreaks through migration counts? An exam­ are to be expected into the foresee­ ination of the data (Figure 1) reveals able future. several interesting patterns.

ONTARIO BIRDS APRIL 2005 39

One important observation is It is unclear what this greater insta­ that the low count in 2002 was not the bility in counts tells us. lowest ever, but in fact there were A closer examination of the three other years with even lower data from even-numbered years counts, 1984, 1998, and 2000. The low only shows a trend within a trend count in 1984 was possibly affected (Figure 2). A hand-drawn best-fit by lower observer effort (see actual curve indicates a longer-term trend count data in Appendix 1). of perhaps 7-10 years between low There is also a clear pattern of and high points in this cycle. This even-numbered years having lower suggests that recent low numbers counts than odd-numbered years; a should not be unexpected. two-year cycle. From 1983 through 2004, there are only two years Conclusion where this cycle was broken, 1986 Blue Jay count data from Holiday and 2004, though both those years Beach show a consistent two-year were "up" years when they should cycle that has only been broken have been "down" years. twice, once unrelated to the pres­ Beginning in 1998, through ence of West Nile Virus. Data from 2002, the pattern of alternating high 1998-2004 indicate greater instabili­ and low counts becomes more ty in numbers, which might be an dynamic, with two record high effect of West Nile Virus, but the counts and three near-record lows. first year the disease was detected

HBMO Blue Jay totals (1983-2004)

700,000 --.------­

600,000 -+------­

500,000 -+------

U) 400,000 +-~~~~~~-

~ 300,000 200,000 100,000 o (") "l!- ID (LI l""- 0:0 0) 0 N (") "l!- ID (LI l""- 0:0 0) 0 N (") "l!- 0:0 0:0 0:0 0:0 0:0 0:0 0:0 0) 0:.: 0) 0) 0) 0) 0) 0) 0) 0) 0 0 0 0 0 ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 0 0 0 0 0 N N N N N Years

Figure 1: Holiday Beach Migration Observatory annual Blue Jay count trend, 1983­ 2004. VOLUME 23 NUMBER 1 40

HBMO Blue Jay totals, even years (1984-2004)

400,000 350,000 300,000 m(/) 250,000 0 200,000 I-- 150,000 100,000 50,000 0 ~ c.o co 0 N ~ c.o co 0 N ~ co co co a> a> a> a> a> 0 0 0 a> a> a> a> a> a> a> a> 0 0 0 ~ ~ ~ ~ ~ N N N Years Figure 2: Holiday Beach Migration Observatory Blue Jay counts for even-numbered years only. in North America, 1999, there was a expected from a normal pattern record high count at Holiday than recent low counts. Beach, and the first year the disease Thus, the variations in migra­ was detected in Ontario, 2001, pro­ tion counts are more easily vided our second highest count explained by normal patterns and ever. It is intriguing to think that trends. The data seem to provide the very low count in 1998 might very little, if any, insight into the signal an earlier presence of the dis­ effects of West Nile Virus on the ease in North America, but without population of Blue Jays migrating actual blood and tissue tests of Blue past Holiday Beach, as there is not Jays from that time, this is only a strong correlation with known speculation. Although the low levels of infection in the region. count in 2002 appears to correlate with an extensive outbreak of West Acknowledgements Nile Virus that year, not all of the I wish to thank the numerous low counts show such a correlation. observers who counted Blue Jays at An examination of the alternating Holiday Beach from 1983-2004. I even (down) years suggests that the am also grateful to the Holiday recent low numbers fall within a Beach Migration Observatory for pattern of longer-term trends. In making Blue Jay data from recent fact, the recent record high counts years (1997-2004) available on their are more outside what might be website. ONTARIO BIRDS APRIL 2005 41

Information Sources Canadian Cooperative Wildlife Health Centre: http://wildLife1.usask.calccwbc2003/wesCnile_virus/wnv_north_america.phP Centers For Disease Control: http://www.cdc.gov/ncidod/dvbid/westniJe/ Holiday Beach Migration Observatory: http://www.bbmo.orgl

Appendix 1: Holiday Beach Migration Observatory Blue Jay annual count data, 1983·2004. Year Count Year Count Year Count Year Count 1983 161,921 1989 346,455 1995 412,186 2001 524,685 1984 21,487 1990 257,745 1996 165,898 2002 72,591 1985 305,152 1991 422,660 1997 383,952 2003 368,998 1986 323,386 1992 165,863 1998 64,689 2004 367,825 1987 306,825 1993 418,187 1999 629,990 1988 106,882 1994 247,837 2000 65,731

Allen T. Chartier, 1442 West River Park Drive, Inkster, Michigan 48141

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VOLUME 23 UMBER 1