Sunday, April 12, 2015

Two Ross's Geese in Nova Scotia

Ross's Geese (Chen rossii) breed in northern Canada and winter in a fragmented range from the Atlantic to the Pacific coast of the US. It typically migrates through central North America. Since the 1950s, this small white goose's breeding and wintering grounds have been expanding eastward. This expansion is thought to have resulted in more contact with Snow Geese and thus more hybridization. (All About Birds, n.d.)

The first Ross's Goose in Nova Scotia was found by Mike King at Hartlen Point, HRM and was present from Dec 31, 2012 to Jan 13, 2013 (King, 2013). The next was at Truro and was found by Cliff Sanderson on Oct 10, 2013. This second bird is likely the same that was spotted at Windsor from Oct 19 - Dec 3 (Hall, 2013).

On April 3, 2015, Karel Allard noticed two small white geese from his home at Mavilette, Digby. Further inspection with his scope confirmed his suspicion, these were two Ross's Geese that represented the third and fourth records of this species in Nova Scotia (Fig. 1).

Figure 1. Two Ross's Geese with two Canada Geese at Mavilette, Digby 5 April, 2015. Photo by Alix d'Entremont.

Johnny and Sandra Nickerson picked me up later in the day on April 3 and we met Karel Allard and Ervin Olsen at Mavilette (Fig. 2). Soon after, Laurel and Kevin Amirault arrived and we all got to see these very rare birds.

Figure 2. Johnny Nickerson, Karel Allard and myself (Alix d'Entremont) at Mavilette, Digby 3 April, 2015. Photo by Ervin Olsen.

The Ross's Goose is very similar to the Snow Goose, but smaller with a relatively small bill, round head and short neck. Hybrids between Ross's Goose and Snow Goose also occur, and these should be considered when presented with a small white goose. In comparison to a Snow Goose, the Ross's Goose has a rounder head with a steeper forehead, no grin patch, a blueish/gray bill base, and a more vertical border at the base of the bill (Fig. 3). Hybrids are intermediate between the two species. (Sibley, 2014)

Figure 3. Ross's Goose at Mavillette (left) and Snow Goose in Pubnico (right). Photos by Alix d'Entremont.

The head shape of the Ross's Geese seemed to change between photos. Some images show a less steep forehead. The birds seemed to flatten their foreheads when actively feeding, making the bill look larger (Fig. 4).

Figure 4. Variability in head shape shown by one of the Ross's Geese at Mavilette, Digby 3 April, 2015. Photos by Alix d'Entremont.

The relatively short necks, rounder bodies and less elongated heads shown by the Ross's Geese are apparent in Figure 5.

Figure 5. The two Ross's Geese at Mavillette, Digby 5 April 2014. Photo by Alix d'Entremont.

Nova Scotia saw its first ever Ross's Goose at the end of 2012 and less than 2 and a half years later we've added another 3 to the provincial total. We can likely attribute the eastwards expansion of this goose's range to the spike in recent records.  


All About Birds (n.d.) Ross's Goose. Retrieved from                                                                            

King, M. (2013) The Discovery of Nova Scotia's First Ross's Goose. Nova Scotia Birds. 55(2), 64-65

Hall, R. (2013) Waterfowl. Nova Scotia Birds. 56(1), 12

Sibley, D.A. 2014. The Sibley Guide to Birds 2nd Ed. Alfred A. Knopf, New York, N.Y.

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