A New Jay in Montana

By Caroline Provost October 31, 2019

Photo by Bob Martinka

Figure 2: Blue Jay range in Montana 2018-2019

Figure 1: Blue Jay range in Montana 2008-2009

As time goes on and seasons change, new sights and sounds come along. You don’t have to look very hard to see this new visitor. Their beautiful blue, white, black, and gray color scheme is unmistakable and their nasally calls can be heard from far away distances. Previously known as an eastern backyard bird, the range of the Blue Jay is expanding Northwest.

The Blue Jay (Cyanocitta cristata) population in North America consists of two segments, one being sedentary and one migratory. Perhaps the jays showing migratory behavior simply have an innate tendency to disperse after nesting season. Or perhaps they’re wandering out for food. (Stewart, 1982). The first step to answering these questions is to make observations and share them. Using eBird.org we can all track bird movements across the continent, including the movement of Blue Jays, providing scientists and the public with valuable information for answering questions about the abundance and distribution of birds.

Looking at the Blue Jay’s eBird sighting map, (https://ebird.org/map/blujay) we can see a noticeable expansion in their range since the early 2000’s. The figures (1 and 2) compare Blue Jay species range over the course of eleven years (2008-2009 and 2018-2019). From these maps we can see a significant increase of Blue Jays in Montana. Although their conservation status is secure, it is fascinating to track Blue Jays as they venture into Montana over the course of just one lifetime. Tracking distribution patterns of species over time is extremely critical, since changes in bird occurrence can often be one of the first signals of widespread environmental or habitat changes.

As of now, we haven’t seen any negative effects from the Blue Jay expansion into our North Western habitats, but it’s a good idea to keep an eye on these intelligent Jays to track potential impacts. It will be interesting to see how or if the Blue Jays interact with or displace other western species, especially species within the same Corvidae family like the Black-billed Magpie.

It is important to have a well-rounded set of data in order to accurately answer questions like, which habitats are they attracted to, or which habitats are they avoiding and why? Together we can lessen the amount of time in between new birds arriving and the time it takes to record their arrival, collectively submitting a greater amount of recordings.

We’re counting on you to track these wandering Blue Jays in your backyard, in the park, or during your afternoon walk. These jays can be seen in town, but will most likely be heard first! Submit any and all Blue Jay sightings to ebird.org/MT!


Paul A. Stewart. 1982. Migration of Blue Jays in eastern North America. North American Bird Bander. https://sora.unm.edu/sites/default/files/journals/nabb/v007n03/p0107-p0112.pdf