This spring has been good for Ibises in Wisconsin as several have already been reported. Ibises are rare Wisconsin visitors that usually make their appearance during migration and only rarely breed in the state. There are two species of Ibis that occasionally pass through: the White-faced Ibis, and the Glossy Ibis. While both are rare, the Glossy is the more uncommon of the two in our state.
Ibises are generally not difficult to identify. They are relatively large birds with bright reddish-brown bodies, complete with iridescent green wings, long legs, and a long, curved bill. However, while an Ibis itself is distinctive, the differences between the White-faced Ibis and the Glossy Ibis can be tricky as some of the defining details are minor.
The White-Faced and Glossy Ibis are both more distinctive during breeding season when their markings are more prominent. In fall, they become almost impossible to distinguish. For this reason, we will focus on breeding season identification tips.
As far as their size, a Glossy Ibis is on average the larger of the two species. Glossy Ibises can range anywhere from 18.9-26 inches. A White-faced Ibis is typically between 18.1-22 inches. While there certainly is a size difference, given their averages it would still not be out of the realm of possibility for a White-faced to be larger than a Glossy. For that reason, this feature alone should not be used to identify.
It is of course not uncommon for birds to stray from their normal range. However, range for these two species can be used as a general guideline. The White-faced Ibis can be found all across the southwestern part of the United States and even reaches as far north as Montana, and as far East as Florida. The Glossy Ibis on the other hand is usually found the Atlantic Coast and in Florida. Therefore, if an Ibis is found in the western states, it is usually a White-faced, however, that is not always the case.
Leg color is a solid species indicator during breeding months. The White-faced Ibis has brightly colored legs ranging from pink to red. The Glossy Ibis on the other hand has dull grayish legs. This feature can be tough to pick out depending how far away the bird is, but even at distance the pink tint of the White-faced Ibis’s legs can be seen.
Eye color is another indicator of distinguishing these two species. The White-faced Ibis has a bright pink eye, whereas the Glossy Ibis has a dark black eye. Again, this feature is much easier to observe when the bird is close but can still be seen with a scope or high powered camera.
Notice the leg and eye color differences in the images below.
The best way to tell the White-faced and Glossy Ibis apart is by their facial patterning. The White-faced Ibis has a namesake white mask that starts near the bill and goes completely around the eye. This thick white mask is unbroken by any other colors. In addition, there is pink coloration going from the start of the bill up to the eye.
Glossy Ibises have a much thinner pattern on their face going near the eye but in most cases not going around it completely. This gives the pattern a “broken” look. In addition, as opposed to the white and pink face of the White-faced Ibis, the outer color on the face is a light blue and the inside color is the same as the rest of the head.
The image below shows a great side-by-side comparison of the two species. Note the facial differences with the Glossy behind the White-Faced.
These identification tips should be enough to correctly determine the species of a breeding plumage Ibis in Wisconsin and other Midwest states. We hope you found this article helpful. Please feel free to contact us to suggest other similar articles or provide feedback.