East Meets West

Is this a black-capped chickadee or a Carolina chickadee? Unless you are an expert birder, you may need to know where it was photographed to be sure which species it is (hint: photographed in Idaho Falls).

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Shenandoah National Park in Virginia was beautiful but mysterious. Biologically, it felt like being in a foreign country. Plants unknown to western forests lined the road and instead of vast vistas of sagebrush or craggy peaks, the views were of unending mountaintops cloaked base to tip in green. A meadowlark sang in a field and I was glad for the connection to home. Only, this wasn’t our western meadowlark, but rather, the Eastern meadowlark.

This served to remind me that there are plenty of animals that have eastern or western cousins. If you travel east past the middle of the country, you will find very similar looking critters in many cases, but, though they seem alike, they have diverged evolutionarily enough they are different species.

This is most common among birds, with the Great Plains often acting like the dividing line. Heading eastward, the range of western species begins to fade out in Eastern Colorado and eastern species begin to increase in the same area. Often, the two species’ ranges overlap there and both species can be found in a fairly narrow band. The line is seldom straight either, with many fingers weaving west and east, sliding up to the north or down south. Within the overlap though, they may hybridize, creating a new challenge for bird watchers.

It is common for eastern and western species to look a little different. For instance, the male western bluebird has a completely blue hood that extends to the chest. The male of the eastern species has a blue head but a rusty throat. The western variety is also lean looking while the eastern species is chunky and round.

The differences between the eastern and western species go beyond subtle changes to their looks. Eastern and western screech owls look pretty similar but can be distinguished from each other based on their very different calls.  The western species gives an, “accelerating series of hollow toots” while the eastern species has a call described as, “a descending whinny”.

At one time, the Baltimore and Bullock’s orioles were merged into one species, the Northern Oriole. Genetic studies in the 1990’s pointed out that there are sufficient genetic differences for these to be considered different species. In appearance, the biggest differences are that the Baltimore oriole has an all-black head and white wing bars while the Bullock’s has a black eye stripe bordered by orange on both sides and a white wing patch. They divide their ranges nearly perfectly down the eastern Montana, Wyoming and Colorado borders, but where they overlap they hybridize shamelessly.

The black-capped chickadee and Carolina chickadee are yet another pair of eastern/western cousins. These two are very challenging to distinguish unless they are side by side. Fortunately, their ranges don’t overlap by very much and many birders use location to help with identification.

Sometimes the separation doesn’t result in broad genetic differences but distinctions can still develop. The eastern marsh wren is brighter colored and has a more vibrant song than its western version. Like the Baltimore/Bullock’s orioles, it is possible that genetics may one day prove that these are different species.

The further east of Colorado you travel, the less familiar the country becomes. Dark hardwood forests eventually dominate the landscape and at times it seems as foreign as the Amazon. Nothing will put you at ease more than seeing a familiar bird, even if it sings a different song or looks a bit unusual.

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Help Idaho Wildlife

When we traveled across the state in October 2017, most of the vehicles we saw using the wildlife management areas did not have wildlife plates. Buying wildlife plates is a great way for non-hunters and hunters alike to support wildlife-based recreation like birding.

C'mon folks, let's help Idaho's wildlife by proudly buying and displaying a wildlife license plate on each of our vehicles! 

See below for information on Idaho plates. Most states have wildlife plates so if you live outside Idaho, check with your state's wildlife department or vehicle licensing division for availability of state wildlife plates where you live. 

And tell them that you heard about it from Nature-track.com!

Wildlife License Plates

Great news! as of 2024, there are three NEW designs for license plates. They still are bluebird, cutthroat trout and elk, but they are beautiful.

Idaho Wildlife license plates provide essential funding that benefits the great diversity of native plants and wildlife that are not hunted, fished or trapped—over 10,000 species or 98% of Idaho’s species diversity. Game species that share the same habitats (such as elk, deer, antelope, sage-grouse, salmon, trout) also benefit from these specialty plates.

No state tax dollars are provided for wildlife diversity, conservation education and recreation programs. Neither are any revenues from the sale of hunting or fishing licenses spent on nongame species. Instead, these species depend on direct donations, federal grants, fundraising initiatives—and the Idaho Wildlife license plates.

Both my vehicles have Bluebird Plates. I prefer the bluebird because the nongame program gets 70 percent of the money from bluebird plates, but only 60 percent of the money from elk and trout plates - 10 percent of the money from elk plates supports wildlife disease monitoring and testing programs (to benefit the livestock industry) and 10 percent from cutthroat plates supports non-motorized boat access.

Incidentally, in 2014, the Idaho Legislature denied the Department of Fish and Game the ability to add new plates or even to change the name of the elk and cutthroat plates (very specific) to wildlife and fish plates, a move that would have allowed for changing images occasionally and generating more revenue. It would seem that they believe that we Idahoans don't want a well funded wildlife program.

I think it is time we let the Legislature know that Idahoan support wildlife funding and that we would like to see these generic plates come to fruition.