Author: Jack Greene

The stunningly beautiful evening grosbeaks are mystery birds that come pouring from the canyons to invade our urban areas on a daily cycle- an eruptive population here in Cache Valley. I always hear their loud chirp notes high above, often beyond sight. They alight in towering trees where they feed and converse with chirps and trills all the while. Highly social, evening grosbeaks are unlike their four solitary grosbeak cousins.

Their behaviors leave me puzzled. – Why this daily ritual of flying back and forth from rural to urban? Where and when do they nest? Do they nest close together given their flock behavior? Are they urban or rural nesters? I was able to find some answers, but there are yet many gaps in on their behaviors and highly variable populations.

The Evening Grosbeaks were of much interest from the late 1800s to the mid-1900s, resulting from its eastward range expansion. Comparatively few recent studies have been conducted other than breeding ecology and behavior in Colorado during the 90’s. They were formerly restricted to the western United States but have expanded their range eastward across the country, perhaps a result of the establishment of box elder trees in eastern cities with abundant seeds that persist through the winter, and outbreaks of eastern forest insects which they feast on.

As is the case with many irruptive, nomadic species, it is difficult to determine their true population. Unfortunately, this bird has almost disappeared from the east once again, and has all but disappeared in the Appalachian Mountains and has suffered heavy declines elsewhere. A focus on understanding what is driving population trends is needed for developing conservation strategies to help it recover.

Potential causes of the Evening Grosbeak’s decline are tar sands mining, which has destroyed large swaths of its Canadian boreal forest breeding habitat. Pesticides used to control spruce budworm, an important food for Evening Grosbeak, may also be a factor. Large numbers are killed by window collisions, and cars during winter, when they gather on roadsides to pick up road salt and grit.

During the breeding season, their behavior is quite secretive, and courtship occurs without elaborate song or display. This secretiveness makes it difficult to study this species’ life history. They breed in high altitude and high latitude various forest types throughout North America. Nests are typically located high up in trees, on horizontal branches well out from the trunk. The female builds the nest, which is a loose saucer of roots and twigs lined with fine grass, moss, rootlets, needles, and lichen. Both parents, generally monogamous, help feed the young. They forage in treetops for insect larvae during the summer, buds in spring, and seeds, berries, and small fruits in winter. They sport heavy, strong beaks which can crack open the toughest shells, including cherry pits- a favorite. Evening Grosbeaks are known to snip off the twigs of Sugar Maple trees and sipping the sweet sap- yum!

As birders and citizen scientists, we must document all we can to supply the much needed dearth of data on this marvelous bird, and report it to www.ebird.org

This is Jack Greene for Bridgerland Audubon- and I’m wild about Utah and its evening grosbeaks!

Credits:

Pictures: Courtesy Pixabay, Alain
Courtesy US FWS,
Text: Jack Greene, Bridgerland Audubon Society

Additional Reading:

Evening Grosbeak, All About Birds, Cornell Lab of Ornithology, Cornell University, https://www.allaboutbirds.org/guide/Evening_Grosbeak

Evening Grosbeak, Coccothraustes vespertinus, Birdweb.com, Seattle Audubon Society, https://www.birdweb.org/birdweb/bird/evening_grosbeak

Evening Grosbeak, Coccothraustes vespertinus, eBird.org, https://ebird.org/species/evegro

Inverted woodpecker, a phrase I use to describe the feeding habits of the amazing nut hatch family. I first became aware of this lovely little songbird growing up in Michigan, where the white-breasted nut hatch was common fare in the north woods. Their little laughing notes were most welcome as I sat on my deer stand where I would watch them search bark crevices for yummy morsels of grubs, insect eggs or seeds they had wedged in for tomorrow’s snack.

Now having lived many years in Utah, it is the red-breasted nut hatch that has replaced this eastern cousin for the most part. Their “yank, yank, yank” vocalizations light up my life whenever and wherever they occur. They prefer conifers but will gladly substitute a deciduous tree, especially those with more furrowed bark. Where there is food or water, infrequently a white-breasted will appear, especially in our higher elevations, although I’ve had them join the red-breasted at our feeder during winter months – a rare treat.

If one spends much time in our Ponderosa pine forests in central and southern Utah, another family member can be found. Unlike the other two more solitary species, these tiny pygmies occur in small flocks and are very chatty. Highly social, the pygmy nut hatch appear to enjoy a food frolic as they fly from tree to tree for feeding and social interaction. Thus, Utah’s blessed with all three North American species of nut hatch.

If you observe them as they search the main stem of a tree, my inverted woodpecker title will be justified. Rather than moving from top to bottom of the tree facing up as do the woodpeckers, the nut hatch prefers head down from top to bottom. They also like hanging upside down on a horizontal limb. Why? Evolution keeps us mysteries well-guarded. I conjecture partitioning might be part of the answer: a phenomenon where bird species will utilize different parts of the tree to avoid competing for resources with other species.

As with all of life, I pay attention to how our shifting climate has been observed or predicted to affect their populations and distribution. As long as there are conifers breeding season, nut hatches are content. They can be found in dry Ponderosa pine foothills, in moist boreal bogs, around tree line in the mountains, and even in planted Christmas tree plantations. Audubon’s seven-year generated climate model shows an overall northward drift of the species’ range with more disruption and range loss in summer than in winter. The nut hatch is a habitat generalist in winter, so summertime climate is the chief concern going forward. However, whether the species adapts in the decades ahead will be determined in large part by the conifer forest health in a changing climate. The projection for species range change from 2000 to 2080 is 19% of summer 2000 range remaining stable and 58% of winter range projected to be stable. It’s my plan to follow them wherever they may go.

Wild about Utah is brought to you in part by our listeners and the Moab area travel council, whose support of tourism events and recreation in Grand county promotes and protects the natural beauty for visitors from across the state of Utah. Information available online at discovermoab.com

This is Jack Green, reading and getting wilder about Utah as days pass.

Credits:

Pictures: Courtesy US FWS, David Brenzinski, Photographer
Contains Sound: Courtesy Kevin Colver
Text: Jack Greene, Bridgerland Audubon Society //Utah State University Sustainability

Additional Reading:

White-breasted Nuthatch, All About Birds, Cornell Lab of Ornithology, https://www.allaboutbirds.org/guide/White-breasted_Nuthatch/id

Red-breasted Nuthatch, All About Birds, Cornell Lab of Ornithology, https://www.allaboutbirds.org/guide/Red-breasted_Nuthatch/id

Pygmy Nuthatch, All About Birds, Cornell Lab of Ornithology, https://www.allaboutbirds.org/guide/Pygmy_Nuthatch/id

Red-breasted Nuthatch, Sitta canadensis, eBird, Cornell Lab of Ornithology, https://ebird.org/species/rebnut