Last updated: July 16, 2019
Article
Identifying Denali's Wolves
![wolf sketches sketches of six wolves identified by Adolf Murie in his book The Wolves of Mount McKinley](/dena/learn/nature/images/fig1_1.jpg?maxwidth=650&autorotate=false)
![tiger stripes a computerized grid overlays a tiger's stripes to identify it](/articles/images/fig2_3.jpg?maxwidth=650&autorotate=false)
Hiby, Lovell, Patil et al. 2009 photo
Methods
Visual recognition of individual wild animals remained an uncommon tool in modern peer-reviewed research until the advent of algorithms which could “prove” that the stripes of a tiger in one photo matched those in another (Fig. 2). Individual identification of wolves provides more opportunity for human error and bias, as they lack clearly defined patterns of other animals such as tigers and leopards. Previous claims of regarding the ability to identify individual wolves during aerial tracking in Denali specifically have drawn criticism.
As part of the Centennial Challenge project, we investigated the potential for using images captured from high-quality trail cameras deployed at den sites and winter wolf kill sites to determine pack composition for packs in Denali through identification of individual wolves. We analyzed over 11,000 photos of wolves from high-quality trail cameras deployed at den sites and winter wolf kill sites from 2013 to 2016.
Field Marks
All photos in this section are from trail cameras unless otherwise noted.![four wolf profiles close up profiles of four wolves](/articles/images/fig5_2.jpg?maxwidth=1300&autorotate=false)
NPS photos
The pattern and color of facial markings can be useful for distinguishing individuals, though to be reliable it requires high quality photos and can be subject to seasonal change.
![five wolf photos five photos depicting wolf chests](/articles/images/collage_fig6.jpg?maxwidth=1300&autorotate=false)
From left to right - trailcam / NPS photo, trailcam / NPS photo, Flickr stock photo, trailcam / NPS photo, Flickr photo / Patrick Kuyper
![wolf collage 2 two images, one showing two gray wolves and a black wolf, the other showing a gray wolf](/articles/images/collage_7.jpg?maxwidth=1300&autorotate=false)
Related wolves within a pack can be quite distinctive in appearance, although this is not always the case. The photo on the left shows a young black wolf (right), a young gray wolf (middle), and a collared black wolf which is graying with age (left). What distinguishing characteristics can you detect on the wolf to the right?
![wolf collage 3 three photos; one shows the angle of dark hair on a wolf's back, the second shows two wolves at a carcass, and the last shows the gradient of dark to light fur on a wolf](/articles/images/collage8.jpg?maxwidth=1300&autorotate=false)
NPS photos
The appearance of the saddle/shoulder/back area is quite variable. On a gray wolf, the level and angle of the area of darker-tipped guard hairs on their back can vary, as can the level and angle of any lighter coloration below that before it transitions to the ventral white. These lines can also be visible on black wolves.
![wolf tails three wolf tails](/articles/images/collage9.jpg?maxwidth=650&autorotate=false)
NPS photos
![lt= two wolves, one adult and one pup](/articles/images/fig10_1.jpg?maxwidth=650&autorotate=false)
NPS photos
Age & Sex
Literature exists on the differences in appearance and morphology of pups (<12 months) compared to adult wolves. The most helpful factors in photos are size, ruff hair, snout length, and to some extent coloration and behavior (Fig 5). In addition to the characteristics of sexual dimorphism (Fig. 6), evidence of sexual organs can sometimes be distinguished in photos and provide additional clues for determining sex of individuals.![lt= illustrated comparison of male and female wolf](/articles/images/fig12_2.jpg?maxwidth=650&autorotate=false)
NPS photo
Conclusions
By combining observations of size, gender, and pelage with additional contextual information about the packs, we believe consistent individual identification is possible assuming a photoset of suitable quality. However, it is important to recognize several limitations and that these results are from the initial stages of investigation. We note several cautions when looking through photos. Specifically, individuals can change in appearance as they age and the angle of the fur and lighting can have a dramatic effect on the appearance of wolves.Next Steps
- We plan to continue to deploy cameras at den and winter kill sites with the goal of accumulating a set of photos for all packs in the eastern region of Denali.
- We could use these techniques to improve our understanding of the contribution of individual wolves to wolf viewing opportunities and wolf viewing patterns.
- These photos could provide a compelling way to educate visitors about wolves and show the beauty and variety of Denali’s fauna.