Grant’s Verses Thomson’s Gazelle
The Zooniverse team are super busy at the moment but hopefully very soon season 10 will be loaded and we can all get cracking with what promises to be a fantastic season full of amazing images.
In the meantime I thought I would post a few notes on those tricky animal pairings that seem to have more than a few people stumped when trying to id them.
To kick it off we will look at Grant’s gazelle and Thomson’s gazelle. If you were treated to perfect photos every time I think you would get the hang of these two pretty quick but with the often blurry or distant images we get on snapshot they can be tricky.
Grant’s gazelle A Thomson’s gazelle A
A; First off there is the overall colouration. Thomson’s has a thick dark stripe across its side, Grant’s usually lacks this but be aware as some Grant’s have a dark stripe too. Not the best distinguishing feature as there can be quite a bit of colour variation.
Grant’s gazelle B Thomson’s gazelle B
B; A better distinction is the facial markings. Grant’s gazelle has a thick black stripe running along the side of the face from the nose passing through the eye to the base of the horns giving a masked look. Thomson’s has the same stripe but it ends at the eye, not passing through. The white band on top of the black stripe is more distinct on Grant’s.
Grant’s gazelle C Thomson’s gazelle C
C; If you get a back-side shot then Grant’s displays a much whiter overall appearance with the white area extending past the root of the tail up onto the back. In Thomson’s the white area stops at the root of the tail. Grant’s tail is white at the root and thin with whispy black end, Thomson’s is dark and fluffy looking. The black vertical bands in Grant’s are also more prominent.
Grant’s and Thomson’s Gazelle
Photo NH53, Flickr (https://creativecommons.org/licenses/by/2.0/)
In a mixed group the smaller size of Thomson’s is evident, although with young animals it is not so obvious. Here you can easily see most of the features discussed above with the Grant’s gazelle comprising the 7 animals to the right back and the Thomson’s gazelle to the left forward. Note the Grant’s gazelle side on at the back, it shows a much darker side stripe than the others more a kin to Thomson’s. Males and females of both antelope have horns with the females usually shorter and thinner. In some females horns are absent. In general Grant’s are more graceful looking than the stocky Thomson’s.