Little Blue Heron (Egretta caerulea), Lower River Road Ponds, Maricopa County

This immature Little Blue Heron was discovered my Troy Corman and Melanie Herring on 15 June 2008 at the Lower River Ponds near Palo Verde, AZ and was photographed at the same time by Melanie. 

Typically casual late spring and summer visitor to Maricopa Co. Overall a rare annual visitor in very limited numbers in AZ.

The most likely species to confuse with immature Little Blue Heron is Snowy Egret.  Typical Snowy Egret has yellow facial skin, all dark bill, yellow feet and pure white plumage.  This first spring Little Blue Heron is already beginning to molt from white juvenile plumage to dark gray plumage of an adult and a few dark patches can be seen.  In addition, immature Little Blue Heron usually has dark tips to the outer primaries which can be seen especially in the lower photograph (Snowy Egret always has pure white primaries). Finally, the bicolored bill, gray facial skin and lack of yellow feet can just barely be made out.  These are all consistent with Little Blue Heron, although rarely immature Snowy Egret can have some of these features. 

Another difference not well treated in field guides is the difference in foraging behavior.  Little Blue Heron is a slow methodical forager, often remaining motionless with an outstretched neck for long periods.  It will often bob its head back and forth while standing still.  Snowy Egret is a much more active forager and usually maintains a folded neck.  It does not bob its head.  These differences can often be seen at distances where other field marks are not obvious.

Little Blue Heron is an ABC Sketch Details species.  Submitting photos to AZFO does not constitute reporting a rare bird for consideration as an official record. To ensure that a record becomes official, details or photos of Sketch Details Species should be sent to the Editors of North American Birds and a full report of Review Species should be submitted to the Arizona Bird Committee. Most rare birds are under _documented and subsequent observers of a rarity are always encouraged to submit reports and additional photos, especially for birds that are challenging to identify.

15 June 2008, photos by Melanie Herring