A Little Egret in Nova Scotia

On May 14, 2015 Rachel Hoogenbos found a small white egret behind her house at Daniel's Head, Cape Sable Island, Shelburne. Johnny Nickerson was notified and he identified it as a rare Little Egret (Egretta garzetta) which is very similar to the relatively more common Snowy Egret (Egretta thula).

Figure 1. Little Egret at Cape Sable Island on May 15, 2015. Photo by Alix d'Entremont

Little Egrets are common and widespread in Eurasia and Australia (Alderfer & Dunn, 2014). These white egrets have bred in Barbados since the mid-1980s, and 15-20 pairs currently breed there each year and fledge 3-4 young per nest. In 2008 they were also found to be breeding on Antigua (Howell et al., 2014).

This Little Egret at Cape Sable Island represents the seventeenth record of this species in Nova Scotia. The last was one at Eastern Passage, HRM present April 21-27, 2013 (NS Birds Vol 55, No 3 Spring 2013). Birds occurring in North America could be from Western Europe or the Caribbean. Little Egrets will likely be found in greater numbers in e. North America as the Caribbean population increases. Individuals from this recently established population could reach us by migrating north in association with returning Snowy Egrets, Little Blue Herons and Tricolored Herons (Howell et al., 2014).

I was privileged to have seen a Snowy Egret at Melbourne on April 19, 2014, so photos of that bird will be used to compared to the Little Egret. For most of the year, Little Egrets have grayish to greenish-yellow lores compared to bright yellow on Snowy. At the height of courtship (only for a short period), the lores of Little Egrets are bright red and rarely bright yellow (Howell et at., 2014). Snowy Egrets also show red lores in high breeding (Alderfer & Dunn, 2014). Both of the birds below do not show bare part coloration consistent with breeding flush. The Cape Sable Island Little Egret shown in Fig. 2 shows grayish lores with a reddish tinge to the anterior region and maybe a slight blueish tinge to the posterior area. This coloration is consistent with the description of the lores as blue-pink at the onset of breeding given by Parsons & Master (2000). This contrasts strongly with the bright yellow lores shown in the Snowy Egret from 2014. Two more field marks to notice in Fig. 2 are the longer bill of the Little Egret and facial feathering that seems to project further at the base of the bill (Howell at al., 2014).

Figure 2. Pale lores and longer bill of the Little Egret compared to the yellow lores of the Melbourne Snowy Egret and its slightly shorter looking bill. Photos by Alix d'Entremont

The two white occipital plumes are clearly visible in Fig. 3 as they are blown about by the wind. Compare this to the numerous breeding plumes of the Snowy Egret that look much more bushy and filamentous. (Howell at al., 2014)

Figure 3. The two lancelot plumes of the Little Egret compared to the bushy, filamentous head feathers of the Melbourne Snowy Egret. Photos by Alix d'Entremont

Svensson et al. (2009) describe the Little Egret as having black legs and dull yellow toes while the Snowy Egret invariably shows distinctly yellowish rear to the lower tarsus and more saturated yellow feet. The extent of the foot colour can be appreciated in Fig. 4. We see the the Little Egret shows only yellowish toes, while the Snowy has the entire foot as well as a small portion of the rear tarsus coloured in a saturated orangish-yellow.

Figure 4. Little Egret and Melbourne Snowy Egret legs and feet. Photos by Alix d'Entremont

On April 11, 2014 during an NSBS field trip led by James Hirtle, an interesting Snowy Egret was discovered at Blanche, Shelburne. It initially caused some excitement due to its atypical lore colour. All other features appear typical of Snowy Egret. Fig 5 shows the similarity in lore colour in both the Cape Sable Island Little Egret and the Blanche Snowy Egret.

Figure 5. Little Egret at left and Blanche Snowy Egret at right with somewhat similar coloured lores. The Snowy Egret photo has been flipped horizontally to allow for easier comparison. Photos by Alix d'Entremont (L) and Keith Lowe (R)

Another interesting Snowy Egret was photographed in Newfoundland on May 14, 2015 which again showed the variability in lore colour of Snowy Egrets. Check Bruce Mctavish's blog post for photos and some discussion.

We should also entertain the possibility of hybrids for these non-characteristic birds. When discussing the Blanche egret, Ian McLaren commented on the typological thinking that a certain species, subspecies or hybrid must have a well defined list of features. Hyrbids may show different characteristics than what are currently documented in the literature. The genetic dilution of the first filial generation of hybrids by further breeding can introduce further complications.

References:

Alderfer, J., J.L. Dunn. 2014. (Ed). Complete Birds of North America, 2nd Edition. National Geographic Society. Washington DC, USA.

Howell, S.N.G.,  I. Lewington & W. Russell. 2014. Rare Birds of North America. Princeton University Press

McLaren, I.A. 2012. All the Birds of Nova Scotia: status & critical identification. Gaspereau Press Ltd, Kentville, N.S., Canada

Parsons, Katharine C. and Terry L. Master. 2000. Snowy Egret (Egretta thula), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/489

Svensson, L., K. Mullarney & D. Zetterstrom. 2009. Collins Bird Guide. 2nd Ed. Princeton University Press, Princeton, New Jersey.